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Due to the growing demand for nutritious foods and the importance of studying the viability of foods produced from native species of the Cerrado, the present study was conducted to characterize baru almond flours produced from fruits subjected to drying. The fruits were dehydrated at temperatures of 40, 60, 80 and 100 ºC in an oven with forced air circulation until constant weight. The samples were analyzed for moisture content, ash, lipids, proteins, carbohydrates, energy value, pH, acidity, soluble solids, apparent specific mass, minerals, phenolics and total flavonoids, carotenoids, antioxidant capacity; and characterized by Fourier transform infrared absorption spectroscopy. The analyses were performed in triplicate and the results were evaluated by analysis of variance and Tukey test (p ≤ 0.05). Baru almond flours showed moisture content ranging from 4.95 to 3.29 g 100 g-1. Drying at a temperature of 100 ºC caused in the samples an increase in apparent specific mass and reduction in pH, soluble solids, antioxidant activity, total phenolics, contents of total flavonoids and carotenoids. The 40 ºC treatment induced lower losses in antioxidant activity, total phenolics and total flavonoids. The results of the FT-IR analysis show loss of nutrients. Drying did not alter the contents of ash, lipids, energy value, potassium, iron, zinc, copper and manganese. Baru almond flour is rich in nutrients and can be an alternative to enrich gluten-free foods

Yellow mombin (Spondias mombin L.) is a plant native to tropical America and occurs in several states in Brazil. Yellow mombin fruit has desirable characteristics for industrialization, but its epicarp (peel) having good nutritional characteristics is discarded. Flour obtained by dehydration processes is an alternative in the food industry for the utilization of by-products. Thus, the objective of this study was to develop a product from an industrial residue and analyze the physical, physicochemical and functional technological characteristics of the yellow mombin epicarp flours produced by drying in an oven, subjected to different temperatures (40, 50, 60 and 70 ºC) and by lyophilization. To reach these final moisture contents, the required times were 11.5, 9.0, 7.0 and 4.5 h, respectively, for the temperatures of 40, 50, 60 and 70 °C. For lyophilization, 24 hours were required. After the samples were dried, they were processed to obtain the flour and evaluated for color, pH, titratable acidity, total soluble solids, bulk density and granulometry. Flour produced by lyophilized epicarp of yellow mombin showed a lighter color and a higher tendency to yellow, greater amount of soluble solids and lower density. FEPL particles were smaller, i.e., finer flour. All flours had low pH values, between 2.65 and 2.83

Yellow mombin (Spondias mombin L.) has an unusual aroma and slightly acidic flavor, which leads to the interest in its fresh consumption or industrial use, causing its epicarp (peel) to be discarded, which generates industrial residue. The nutritional value of fruit epicarp is almost always high and, in some cases, may be even higher than the that of the fruit itself. The objective of this study was to evaluate the flours produced from the epicarp of yellow mombin (Spondias mombin L.), through conventional drying and lyophilization. Contents of water, ash, lipids, proteins and minerals were analyzed and carbohydrate content and energy value were determined. Moisture content was below 8.87%, being within the acceptable limit. The flours showed high contents of ash, lipids and proteins, with values above 5.61, 7.76 and 11.90%, respectively. Fe, Zn and Mn contents were above the daily intake recommendation. The temperatures used to dehydrate yellow mombin epicarp did not cause nutritional alteration in the flours compared with the flour from the lyophilized epicarp

The ‘Gueroba’ fruit can be used to produce flours with potential for the development of new products from the ‘Cerrado’ socio-biodiversity. The objective was to estimate the drying kinetics and determine the effective diffusion coefficient and activation energy for the pulp of ‘gueroba’ fruits subjected to different drying temperatures. ‘Gueroba’ fruits were manually pulped, removing the mesocarp with the epicarp, and this material was identified as the pulp. The material was subjected to oven drying at temperatures of 40, 50, 60 and 70 °C. Nonlinear regression models were fitted to the experimental data. The most adequate model was selected through the coefficient of determination, mean relative and estimated errors, Chi-square test, AIC and BIC. As the drying temperature increases, the processing time to achieve the same moisture content decreases, due to the increase in water diffusivity inside the product. The Midilli model showed the best fit to the experimental data obtained. The effective diffusion coefficients of the pulp of ‘gueroba’ fruits showed magnitudes between 3.11 x 10-9 to 5.84 x 10-9 m2 s-1 for temperatures from 40 to 70 °C. The activation energy of the process was 18.34 kJ mol-1.

This work aimed to study the drying kinetics of canola seeds, fit mathematical models and obtain the effective diffusion coefficient. Canola seeds with initial moisture content of 0.3653 (decimal, d.b.) were subjected to drying in a forced ventilation oven at temperatures of 40, 60, 80 and 100 °C and relative humidity of 37.15, 16.93, 8.35, 4.41 and 2.47%, respectively. The samples were dried on trays without perforations, containing approximately 77 g, in three replicates. A final moisture content of 0.080 ± 0.004 (decimal, d.b.) was established to determine the drying curves and fit the mathematical models. The mathematical models were selected considering the mean estimated error, chi-square, coefficient of determination, mean relative error, and Akaike (AIC) and Bayesian (BIC) information criteria. Drying time decreased with increasing temperature. Based on the best values of the statistical parameters and together with the Akaike and Bayesian information criteria, the Page model was selected to represent the drying kinetics of canola seeds. The effective diffusion coefficients showed magnitudes between 0.153x10-11 and 1.221x10-11 (m2 s-1), and their values increased with temperature increase, being described by the Arrhenius equation, with activation energy of 33.94 kJ mol-1, an important piece of information to consider when designing drying equipment

The objective of this study was to determine the desorption isotherms and isosteric heat of Annona crassiflora Mart. seeds, using Akaike information criterion (AIC) and Schwarz’s Bayesian information criterion (BIC) to assist in the choice of the nonlinear regression model. The desorption isotherms were determined by indirect static method and water activity was obtained using the instrument HygroPalm; the product was put in the device in B.O.D. chamber set at 10, 20, 30 and 40 °C. Several nonlinear regression models were fitted to the experimental data by the Gauss-Newton method. The desorption isotherms of Annona crassiflora Mart. seeds can be represented by the models of Chung-Pfost, Copace, Modified GAB, Modified Henderson, Modified Oswin, Sabbah and Sigma Copace. However, the Sigma Copace model showed better fit to the experimental data, with lower AIC and BIC values, being chosen to represent the desorption isotherms of Annona crassiflora Mart seeds. Isosteric heat increased with decreasing moisture content, requiring a greater amount of energy to remove water from seeds, with values ranging from 2541.64 to 2481.56 kJ kg-1, for the moisture content range from 5.69 to 14.93% on a dry basis.

Yellow mombin (Spondias mombin L.) fruits have relevant characteristics for industrialization and exhibit a pleasant aroma and sour-sweet taste, with significant amounts of vitamin A and carotenoids in their epicarp. The objective was to fit different mathematical models to the experimental data, using as criteria to select the best model - the Akaike Information Criteria (AIC) and Schwarz’s Bayesian Information Criteria (BIC), as well as to evaluate the effective diffusion coefficient and to determine the activation energy for yellow mombin epicarp submitted to different drying conditions. The experiment was carried out at the Instituto Federal de Educação, Ciência e Tecnologia Goiano, Brazil The epicarp of yellow mombin fruits with initial moisture content of 2.89 (dry basis, d.b.) were submitted to drying at temperatures of 40, 50, 60 and 70 °C until final moisture contents of 0.11, 0.10, 0.09 and 0.08 (d.b.), respectively. The Midilli model showed the best fit to the experimental data obtained. The choice of the model was confirmed by the AIC and BIC criteria. The increase of the drying temperature promoted increase in the effective diffusion coefficient, and the activation energy of the process was 21.50 kJ mol-1.

Safflower is a crop of high economic value with high oil concentration in its seeds and great industrial versatility, besides various benefits to human health. As with other agricultural crops, it is common to store safflower to make it available in different periods of the year and, due to its hygroscopic characteristics, studies evaluating the effect of temperature and air relative humidity on its moisture content become relevant. Thus, the objective of the present study was to determine the water adsorption isotherms of safflower seeds and analyze their thermodynamic properties. Moisture contents of 6.5, 6.9, 7.3, 7.7, 8.3 and 9.1% (dry basis) were obtained by adsorption under controlled conditions of temperature (30 °C) and relative air humidity (90%). The adsorption isotherms were obtained by the indirect static method at different temperatures (10, 20, 30 and 40 °C). As temperature increased, for the same moisture content, there was an increase in water activity and, for constant water activity, the values of equilibrium moisture content decreased with increasing temperature. Chung-Pfost model showed the best fit to describe the phenomenon of hygroscopicity of safflower seeds. The thermodynamic properties were influenced by the moisture content of the seeds, reducing the energy necessary for water absorption in the product with the increase in adsorption, and the enthalpy-entropy theory was controlled by enthalpy. RESUMO O cártamo é uma cultura de elevado valor econômico que possui alto teor de óleo nos grãos e grande versatilidade industrial com vários benefícios à saúde humana. Assim, como outras culturas agrícolas é comum o armazenamento do cártamo para disponibilização em diferentes épocas do ano, e devido suas características higroscópicas tornam-se relevantes estudos que avaliem o efeito da temperatura e da umidade relativa do ar no teor de água. Deste modo, objetivou-se neste estudo determinar as isotermas de adsorção de água das sementes de cártamo e analisar as propriedades termodinâmicas. Os teores de água de 6,5; 6,9; 7,3; 7,7; 8,3 e 9,1% (base seca) foram obtidos por adsorção em condições controladas de temperatura (30 °C) e umidade relativa do ar (90%). As isotermas de adsorção foram obtidas pelo método estático indireto em diferentes temperaturas (10, 20, 30 e 40 °C). Com o aumento da temperatura, para um mesmo teor de água, tem-se elevação da atividade de água e, para uma atividade de água constante, os valores do teor de água de equilíbrio diminuíram com o aumento da temperatura. O modelo de Chung-Pfost apresentou o melhor ajuste para descrever o fenômeno de higroscopicidade das sementes de cártamo. As propriedades termodinâmicas foram influenciadas pelo teor de água das sementes, reduzindo a energia necessária para a absorção de água no produto com o aumento da adsorção, sendo a teoria da compensação entalpia-entropia controlada pela entalpia.

Grain sampling requires the use of appropriate and accurate equipment. This study aimed to compare grain samplers, manual and mechanical, used in the sampling of soybean loads, during their reception by storage units. The used devices were the manual sampler with 1.80 m length and three opening stages, 2.10 m length and three opening stages; and 2.10 m length and one opening stage, besides the mechanical sampler (pneumatic) and the pelican sampler. The analyzed parameters were the contents of impurity, broken grains, pods, immature grains, and moisture. The significance of effect of treatment was determined by F Test and the means were compared by Tukey test (p < 0.05). The devices used for sampling of soybean grains in vehicles, during their reception by storage units, affect the determination of broken grains, pods and immature grains. However, there was no difference between the types of sampling equipment in the determination of impurity content, and the pelican sampler collected greater percentages of pods and immature grains from the sampled vehicles.

Baru (Dipteryx alata Vogel) is a native tree of the Cerrado. The drying and milling process can be an alternative for the use and conservation of baru fruits. The objective of this study was to evaluate the effect of drying on the nutritional characteristics of the epicarp + mesocarp flour of baru fruits. The fruits were collected in the municipality of Santa Helena de Goiás, Goiás, sanitized and submitted to drying in an oven with air circulation at temperatures of 40, 60, 80 and 100 ºC until they had a constant mass. The analyses were performed in triplicate and the results evaluated by analysis of variance and Tukey test (p ≤ 0.05). Flours produced from dehydrated fruits had a reduction in lipid content (treatments 100 °C), energy value (60 and 80 °C), pH, soluble solids, apparent specific mass and carotenoids in relation to the control sample, and high values of acidity, antioxidant activity and total phenolics. FTIR analysis showed nutrient loss. RESUMO O baru (Dipteryx alata Vogel) é uma arbórea nativa do cerrado. O processo secagem e moagem pode ser uma alternativa para o aproveitamento e conservação dos frutos de baru. O objetivo deste estudo foi avaliar o efeito da secagem dos frutos sobre as características nutricionais das farinhas do epicarpo + mesocarpo de baru. Os frutos foram coletados na cidade de Santa Helena de Goiás, Goiás, higienizados e submetidos à secagem em estufa com circulação de ar nas temperaturas de 40, 60, 80 e 100 ºC até apresentarem massa constante. As análises foram realizadas em triplicata e os resultados avaliados por análise de variância e teste Tukey (p ≤ 0,05). As farinhas produzidas de frutos desidratados apresentaram redução dos teores de lipídeos (tratamentos 100 °C), valor energético (60 e 80 °C), pH, sólidos solúveis, massa especifica aparente e carotenoides em relação a amostra controle, e valores elevados de acidez, atividade antioxidante e fenólicos totais. A análise de FTIR demostrou perda de nutrientes.

Jambu is a vegetable originally from the northern region of Brazil, has bioactive properties, being little explored by other regions, due to its high peresivity. And one of the methods to increase the shelf life of plant products is the removal of water. The objective of this work was to evaluate the drying kinetics of jambu leaf mass. Two treatments were carried out: The mass of fresh jambu leaves and the mass of fresh jambu leaves with the addition of drying foam, both submitted in an oven with forced air circulation at temperatures (50, 60 and 70 °C and thickness of 1.0 cm). The proximate composition of the materials was performed before and after drying. Twelve mathematical models were tested on drying kinetics data and thermodynamic properties were calculated. The parameters of the proximate composition for the mass of leaves and foam after drying were: Moisture content of (2 to 7%), ash content of (13 to 17%), protein content of (22 to 30%), lipids of (0.6 to 4%) and total titratable acidity (0.20 to 0.28%) of tartaric acid. The models that best fit the experimental data to describe the drying kinetics of jambu masses were: Wang & Singh. The use of foam mat presented higher values of effective diffusion coefficient and activation energy and lower values of enthalpy and entropy, reducing the drying time.

In the present study, the objective was to fit different models to the experimental data of drying of tamarind (Tamarindus indica L.) seeds and to select the best model, to determine the effective diffusion coefficient, activation energy and thermodynamic properties for the process during drying at different temperatures. The experiment was carried out at the Laboratory of Post-Harvest of Vegetable Products of the Instituto Federal Goiano (Federal Institute Goiano) - Campus of Rio Verde, GO, Brazil. Seeds with initial moisture content of 18 ± 0.25% dry basis were oven dried with forced air ventilation, at controlled temperatures of 45, 60, 75 and 90 °C in four repetitions. Nonlinear regression models used to describe the phenomenon were fitted to the experimental data. To represent the drying of tamarind seeds, the Midilli model was selected for the range from 45 to 60 ºC and the Two terms model was selected for the range from 75 to 90 ºC. The effective diffusion coefficient increases with the increase of drying air temperature, being described by the Arrhenius equation, with activation energy of 35.16 kJ mol-1. Enthalpy and entropy decreases, while Gibbs free energy increases with increasing drying temperature. RESUMO No presente estudo, objetivou-se ajustar diferentes modelos aos dados experimentais da secagem das sementes de tamarindo (Tamarindus indica L.) e selecionar o melhor modelo, determinar o coeficiente de difusão efetivo, a energia de ativação e as propriedades termodinâmicas para o processo, durante a secagem em diversas temperaturas. O experimento foi conduzido no Laboratório de Pós-Colheita de Produtos Vegetais do Instituto Federal Goiano - Campus Rio Verde. As sementes com teor de água inicial de 18 ± 0,25% base seca, foram secas em estufa com ventilação de ar forçada, nas temperaturas controladas de 45, 60, 75 e 90 °C, em quatro repetições. Aos dados experimentais foram ajustados a modelos de regressão não linear utilizados para descrição do fenômeno. Para representar a secagem das sementes de tamarindo o modelo de Midilli foi selecionado para a faixa de 45 a 60 ºC, e para 75 a 90 ºC o modelo ajustado foi o de Dois termos. O coeficiente de difusão efetivo aumenta com a elevação da temperatura do ar de secagem, sendo descrito pela equação de Arrhenius, com energia de ativação de 35,16 kJ mol-1. A entalpia e entropia decrescem, enquanto a energia livre de Gibbs aumenta com o incremento da temperatura de secagem.

Drying is an important step in the post-harvest processes as a way of product conservation and quality preservation. In this context, this study aimed to evaluate the effect of continuous and intermittent drying of maize grains with different rest periods on the integrity of their micro- and macroscopic structures. Maize grains were harvested with a moisture content of 0.3399 ± 0.001 dry basis (db) and subjected to continuous and intermittent drying with 4, 8, 12, and 16 hours of rest period. An experimental fixed-bed dryer, with controlled drying air conditions at a temperature of 100 °C and air flow of 1.5 m3 min.−1 m−2 (12 m3 min.−1 m−3), was used. Continuous drying was completed with a moisture content of 0.1628 ± 0.0003 db, whereas intermittent drying was interrupted with 0.2195 ± 0.0002 db and resumed after rest. The drying rate, integrity through grain images, the conformation of particles through scanning electron microscopy, and cell membrane integrity were evaluated. The drying rate increased with an increase in the rest period, the increase in rest period reduced the intensity of cracks, and the reduction in rest period led to higher dispersion and reduction in the size of starch granules and lower integrity of cell membranes. Drying is an important step in the post-harvest processes as a way of product conservation and quality preservation. In this context, this study aimed to evaluate the effect of continuous and intermittent drying of maize grains with different rest periods on the integrity of their micro- and macroscopic structures. Maize grains were harvested with a moisture content of 0.3399 ± 0.001 dry basis (db) and subjected to continuous and intermittent drying with 4, 8, 12, and 16 hours of rest period. An experimental fixed-bed dryer, with controlled drying air conditions at a temperature of 100 °C and air flow of 1.5 m3 min.−1 m−2 (12 m3 min.−1 m−3), was used. Continuous drying was completed with a moisture content of 0.1628 ± 0.0003 db, whereas intermittent drying was interrupted with 0.2195 ± 0.0002 db and resumed after rest. The drying rate, integrity through grain images, the conformation of particles through scanning electron microscopy, and cell membrane integrity were evaluated. The drying rate increased with an increase in the rest period, the increase in rest period reduced the intensity of cracks, and the reduction in rest period led to higher dispersion and reduction in the size of starch granules and lower integrity of cell membranes.

Mechanical properties of agricultural products are essential for a proper project design or processing equipment dimensioning, as well as for establishment of parameters on the supported load. An experiment was set up in a completely randomized design, with five treatments (continuous and intermittent drying under 4, 8, 12, and 16 h of rest period) and four replications, to evaluate the effect of intermittent drying. Corn kernels of the cultivar Cargo TL were harvested with a moisture content of 25.37% wb and submitted to drying in an experimental fixed bed dryer set to a temperature of 100 °C and an airflow of 1.5 m3 min-1 m-2. Drying was performed until the kernels reached a moisture content of 14±0.3% wb. The process was interrupted in the intermittent drying with a moisture content of 18±0.2% wb and continued after rest period until the final moisture content was reached. The analysis consisted of 10 kernels randomly selected per replication and submitted to the uniaxial compression test after determining their dimensions. Rupture force, maximum deformation, energy to rupture point, modulus of toughness, hardness, and drying rate during drying were evaluated. The increase in rest period promoted a linear increase in the rupture force and hardness. Modulus of toughness, energy to rupture point, and maximum deformation were not affected by the rest period. The increase in rest period contributed to increasing the drying rate. RESUMO As propriedades mecânicas de produtos agrícolas são fundamentais para o correto desenho de projetos ou dimensionamento de equipamentos de processamento e estabelecimento de parâmetros sobre a carga suportada. Para avaliar o efeito da secagem com intermitência, foi montado um experimento em delineamento inteiramente casualizado, com cinco tratamentos (secagem contínua e intermitente com 4; 8; 12 e 16 h de repouso) e quatro repetições. Os grãos de milho, cultivar Cargo TL, foram colhidos com teor de água de 25.37% b.u., submetidos a secagem em um secador experimental de camada fixa, ajustado à temperatura de 100 ºC e fluxo de ar de 1.5 m3 min-1 m-2. A secagem decorreu até que os grãos atingissem o teor de água de 14±0.3% b.u. Para a secagem intermitente o processo foi interrompido com 18±0.2% de teor de água b.u. e prosseguiu após o repouso, até atingir o teor de água final. Para a análise foram selecionados aleatoriamente 10 grãos por repetição e submetidos ao teste de compressão uniaxial depois de determinar as suas dimensões. Avaliou-se a força de ruptura, deformação máxima, energia consumida até o ponto de ruptura, módulo de tenacidade, dureza e taxa de redução da água durante a secagem. Concluiu-se que, o aumentou do tempo de repouso promoveu um aumento linear nos valores da força de ruptura e dureza; o módulo de tenacidade, energia e deformação não foram afetados pelo tempo de repouso; o aumento do tempo de repouso contribuiu para o aumento da taxa de redução da água.

espanolRESUMEN El estudio de las caracteristicas mecanicas de los productos agricolas es importante para que los equipos puedan desarrollarse y lograr la maxima eficiencia sin comprometer la calidad final de los alimentos. Las grietas y roturas de las semillas se producen cuando estan expuestas a tensiones que exceden la resistencia del material. El objetivo de este trabajo fue evaluar algunas pro piedades mecanicas de las semillas de sorgo de sacarina (Sorghum bicolor L. Moench) con diferentes contenidos de humedad. Las semillas se cosecharon en el municipio de Santa Helena - GO, Brasil, y presentaron un contenido de humedad inicial de 0.307 base seca (b.s.). Para cada contenido de humedad obtenido (0,307; 0,258; 0,212; 0,170; 0,130 y 0,093 b.s.), las muestras fueron homogeneizadas y luego analizadas. Las pruebas de compresion uniaxial se realizaron en una muestra de 15 semillas para cada contenido de humedad. Para esta determinacion se utilizo la maquina de prueba universal Analizador de textura TA Hdi, con una celda de carga de compresion de 250 N. Nuestros resultados evidenciaron que la fuerza de compresion necesaria para deformar las semillas de sorgo disminuyo con el aumento del contenido de humedad, mientras que los valores del modulo de deformidad proporcional se incrementaron con la reduccion tanto del contenido de humedad como de la deformacion. Ademas, la reduccion del contenido de humedad aumento la fuerza requerida para romper las semillas. EnglishABSTRACT Study of the mechanical characteristics of agricultural products is crucial to the development of equipment that can achieve the maximum efficiency without compromising the final product quality. Seeds crack and break when exposed to stresses that exceed their resistance to rupture. In this study, we aim to assess the mechanical properties of saccharine sorghum (Sorghum bicolor L. Moench) seeds at different moisture contents. The seeds were harvested in the municipality of Santa Helena - GO, Brazil and indicated an initial moisture content of 0.307 (d.b.). For each moisture content obtained (0.307, 0.258, 0.212, 0.170, 0.130, and 0.093 d.b.), samples were homogenized and subsequently analyzed. Compressive tests were performed through uniaxial tests in a sample of 15 seeds for each moisture content. In these tests, the "TA Hdi Texture Analyzer" universal testing machine was used, with a 250-N compression load cell. Our results indicated that the compressive force required to deform saccharine sorghum seeds decreased with increasing moisture content, whereas values of proportional modulus of deformity increased with both reduced moisture content and deformation. In addition, the reduction in moisture content caused an increase in the force required to rupture the seeds.

‘Okara’ is the insoluble part obtained after the aqueous extraction of soybeans, generated in large quantities as a by-product of the ‘tofu’ industry or soybean water-soluble extract. This work aimed to study ‘okara’ convective drying kinetics, determine the effective diffusion coefficient, and obtain activation energy and thermodynamic properties under different drying conditions. The by-product ‘okara’ was obtained from the processing of BRS 257 soybean water-soluble extract, homogenized and dried in a forced-air oven at temperatures of 40, 50, 60 and 70 °C until constant weight. Among the analysed models, Wang & Singh was selected to represent the drying phenomenon. Effective diffusion coefficient increased with the temperature rise, and the activation energy for the net diffusion in the drying was 28.15 kJ mol-1. Enthalpy and Gibbs free energy increased with the elevation of drying temperature.

‘Sucupira-branca’ (Pterodon emarginatus Vogel) is a tree from ‘Cerrado’ and stands out mainly for its pharmacological properties; however, there are no technological information about its post-harvest operations. Thus, the aim of this study was to determine the sorption isotherms of ‘sucupira-branca’ fruits for different air conditions and obtain the values of desorption isosteric heat, depending on the equilibrium moisture content of the product. The equilibrium moisture content of ‘sucupira-branca’ fruits was determined by dynamic method for temperatures of 25, 30, 35 and 40 °C and water activities for each temperature between 0.270 and 0.775. The models Chung-Pfost, Copace, Modified Halsey, Oswin Modified and Sigma Copace obtained high coefficient of determination (R2) and low chi-square (χ2), relative mean error (P) and estimated mean error (SE), and the Copace model was selected to represent the desorption isotherms. The isosteric heat increases with the reduction of equilibrium moisture content and required more energy to remove water from the ‘sucupira-branca’ fruit. RESUMO A sucupira-branca (Pterodon emarginatus Vogel) é uma árvore do Cerrado e se destaca principalmente por suas propriedades farmacológicas; entretanto, inexistem informações tecnológicas sobre as operações de pós-colheita. Desta forma, objetivou-se, com este trabalho, determinar as isotermas de dessorção dos frutos de sucupira-branca para diferentes condições do ar, bem como obter os valores do calor isostérico de dessorção em função do teor de água de equilíbrio do produto. O teor de água de equilíbrio dos frutos de sucupira-branca foi determinado pelo método dinâmico para temperaturas de 25, 30, 35 e 40 °C e atividades de água para cada temperatura, entre 0,270 a 0,775. Os modelos Chung-Pfost, Copace, Halsey Modificado, Oswin Modificado e Sigma Copace obtiveram elevado coeficiente de determinação (R2) e baixo Qui-quadrado (χ2), erro médio relativo (P) e estimado (SE), sendo o modelo de Copace selecionado para representar as isotermas de dessorção. O calor isostérico aumenta com a redução do teor de água de equilíbrio, sendo relevante maior quantidade de energia para retirar a água dos frutos de sucupira-branca.

The objectives of this study were to fit different mathematical models to experimental data of drying of sunflower grains, determine and evaluate the effective diffusion coefficient and obtain the activation energy for the process during the drying under various conditions of air. The sunflower grains were collected with an initial moisture content of 0.5267 dry basis (d.b.) and dried in an oven with forced air ventilation under five temperature conditions: 35, 50, 65, 80 and 95 °C, until reaching the moisture content of 0.0934 ± 0.0061 (d.b.). Among the analyzed models, Wang and Singh showed the best fit to describe the drying phenomenon. The effective diffusion coefficient of sunflower grains increased with the increment in air temperature and has activation energy for liquid diffusion in the sunflower drying of 29.55 kJ mol-1. RESUMO Objetivou-se, neste trabalho, ajustar diferentes modelos matemáticos aos dados experimentais da secagem dos grãos de girassol, determinar e avaliar o coeficiente de difusão efetivo e obter a energia de ativação para o processo durante a secagem em diversas condições de ar. Os grãos de girassol foram colhidos com teor de água inicial de 0,5267 base seca (b.s) e submetidos à secagem em estufa com ventilação de ar forçada em cinco condições de temperatura: 35, 50, 65, 80 e 95 °C, até atingir o teor de água de 0,0934 ± 0,0061(b.s). Dentre os modelos analisados, o de Wang e Singh, apresentou os melhores ajustes e foi escolhido para descrever o fenômeno de secagem. O coeficiente de difusão efetivo aumenta com a elevação da temperatura do ar e apresenta uma energia de ativação para a difusão líquida na secagem do girassol de 29,55 kJ mol-1.

Environment and storage time influence stored seed quality, especially for oilseeds such as castor beans because they have a high lipid content and are more prone to deterioration. This study evaluated the physiological quality of seeds from three castor bean genotypes stored at 10 and 20°C for 300 days. The experimental design was completely randomized, with 4 replications, in a 2 x 6 (2 temperatures x 6 storage periods) split-plot design. The seeds were placed in low-density polypropylene bags and stored in climatic chambers at 10 and 20°C, in which the temperature and relative humidity were registered. Physiological quality (germination, germination rate index, emergence, rate of emergence, electrical conductivity and accelerated aging) were evaluated at baseline and after 60, 120, 180, 240, and 300 days of storage. Castor seeds of genotype EVF 106 showed better physiological quality when stored at 10°C. Castor seeds of genotype EVF 701 could be stored at 10 and 20°C for 300 days. Castor seeds of genotype EVF 712 presented reduced physiological quality during their 300 days in storage, regardless of temperature.

Grain quality determination involves important stages such as collection of the representative sample, homogenization, and dilution. The interrelation among sampling, homogenization, and working sample size is essential to the reliability of the information generated. Therefore, this work aimed to analyse the performance of mechanical homogenizers used in the commercialization of grains in Brazil, as a function of the size of the working sample masses during grain classification. The samples were homogenized and diluted in Boerner, 16:1 multichannel splitter, and 4:1 multichannel splitter until reaching masses of 0.025, 0.050, 0.075, 0.100 and 0.125 kg to determine the level of damaged grains. A 3 x 4 x 5 factorial design was used, meaning three treatments relative to homogenizers (Boerner, 16:1 multichannel splitter, and 4:1 multichannel splitter), four dilutions (4, 8, 12 and 16% damaged grains), and five grain sample sizes (0.025, 0.050, 0.075, 0.100 and 0.125 kg) with nine repetitions. The means were compared by Tukey test and to the original means of prepared samples (4, 8, 12, and 16%) by Student’s t-test. Working samples can be utilized with masses between 0.025 and 0.125 kg to classify damaged soybeans grains. The devices Boerner, 16:1 multichannel splitter, and 4:1 multichannel splitter are similar in the reduction and homogenization of soybean samples for different levels of damaged grains and sample sizes. RESUMO A determinação da qualidade de grãos envolve etapas importantes como a retirada da amostra representativa do lote, homogeneização e diluição. A inter-relação entre a amostragem, homogeneização e o tamanho da amostra de trabalho é fundamental para a fidedignidade da informação gerada. Assim, objetivou-se analisar o desempenho de homogeneizadores mecânicos utilizados na comercialização de grãos no Brasil, em função do tamanho das massas de amostras de trabalho, durante a classificação de grãos de soja. As amostras foram homogeneizadas e diluídas nos equipamentos Boerner, quarteador multicanais 16:1 e quarteador multicanais 4:1 até se obter uma massa de amostras de trabalho com 0,025, 0,050, 0,075, 0,100 e 0,125 kg para determinação do nível de grãos avariados. Foi utilizado o delineamento fatorial 3 x 4 x 5, sendo três tratamentos correspondentes aos homogeneizadores, quatro diluições (4, 8, 12 e 16% de grãos avariados) e cinco massas de grãos para trabalho, com nove repetições. As médias foram testadas entre si pelo teste Tukey e comparadas com as médias originais das amostras preparadas (4, 8, 12 e 16%) pelo teste t de Student. As amostras de trabalho podem ser utilizadas com massas entre 0,025 e 0,125 kg para a classificação de grãos de soja avariados. Os homogeneizadores e diluidores do tipo Boerner, quarteador multicanais 16:1 e quarteador multicanais 4:1 são semelhantes na redução e homogeneização de amostras de grãos de soja para diferentes níveis de grãos avariados e tamanhos de amostras.

Thermodynamic properties provide information on energy demand and kinetic parameters in water sorption processes in agricultural products. Such information is essential to analyze and scale drying and storage equipment. The objective of this study was to determine the thermodynamic properties involved in the water desorption process in Buchenavia capitata (Vahl) Eichler seeds with moisture contents ranging from 13.31 to 7.21% dry basis (d.b.), obtained by the indirect static method, at temperatures of 10, 20, 30 and 40 °C. The latent heat of vaporization, differential entropy and Gibbs free energy increase with the reduction of the moisture content of the seeds. The enthalpy-entropy compensation theory is valid for the desorption process, which is controlled by the enthalpy. The desorption of water in the seeds is not a spontaneous process. RESUMO As propriedades termodinâmicas fornecem informações sobre a exigência energética e parâmetros cinéticos nos processos de sorção da água em produtos agrícolas. Tais informações são essenciais para analisar e dimensionar equipamentos para secagem e armazenamento. Assim, objetivou-se, neste trabalho, determinar e analisar as propriedades termodinâmicas envolvidas no processo de dessorção da água de sementes de Buchenavia capitata (Vahl) Eichler com teor de água na faixa de 13,31 a 7,21% base seca (b.s.), sendo estes obtidos pelo método estático indireto, nas temperaturas de 10, 20, 30 e 40 °C. O calor latente de vaporização, a entropia diferencial e a energia livre de Gibbs aumentam com a redução do teor de água das sementes. A teoria da compensação entalpia-entropia é válida para o processo de dessorção, sendo este controlado pela entalpia. A dessorção da água nas sementes é um processo não espontâneo.

Baru (Dipteryx alata Vogel) is a tree species that is part of the group of native species of the Cerrado and occurs mainly in Central Brazil, being valued for its various uses. Thus, the present work was carried out with the objective of studying the kinetics of drying of the mesocarp of baru fruits, performing the analysis of the thermodynamic properties, as well as evaluating the effect of drying on the color of the flour produced from the mesocarp. The mesocarp of baru fruits was placed in stainless steel trays, and dried at 40, 50, 60 and 70 ºC in a forced circulation oven until the moisture content of 0.12 dry basis (d.b.) was reached. Subsequently, the experimental data of the drying were adjusted with the mathematical models frequently used, and color was evaluated after the drying. It is concluded that the Wang & Singh model was selected to represent the drying curves of the baru mesocarp. For the thermodynamic properties, with increasing drying air temperature, the entropy and enthalpy values decreased while the Gibbs free energy increased. Regarding color, the results showed that with the increase of drying air temperature, there is a change in color, which indicates loss in the qualitative aspect.

The objective of this study was to determine the desorption isotherms of 'cajuzinho-do-cerrado' achenes (Anacardium humile St. Hil.) in various conditions of temperature and water activity, as well as to select the one that best represents the phenomenon and to determine the isosteric heat of desorption. The fruits were collected at the Emas National Park, in the municipality of Mineiros-GO, Brazil, pulped and then subjected to drying in silica gel at temperature of 25 ± 2 °C until the moisture contents of 17.6, 13.6, 11.1, 8.7 and 5.3 (d.b.%). After drying, the desorption isotherms were determined by the indirect static method. The water activity (Aw) was determined at different temperatures, and the achenes were placed in a B.O.D. chamber, regulated at 10, 20, 30 and 40 °C. Data of hygroscopic equilibrium moisture content were fitted to different mathematical models through non-linear regression analysis, using the Gauss-Newton method. The Copace model was the one that best represented the hygroscopicity of 'cajuzinho-do-cerrado' achenes, while the integral isosteric heat of desorption of 'cajuzinho-do-cerrado' achenes for the moisture content range of 4.51 to 13.40 (% d.b.) varied from 2,734.82 to 2,548.49 kJ kg-1. RESUMO Objetivou-se, com este trabalho, determinar as isotermas de dessorção de aquênios de cajuzinho-do-cerrado (Anacardium humile St. Hil.) em diversas condições de temperatura e atividades de água e selecionar aquela que melhor representa o fenômeno e determinar o calor isostérico de dessorção. Os frutos foram coletados no Parque Nacional das Emas, no município de Mineiros - GO, despolpados e em seguida submetidos à secagem em sílica gel a temperatura de 25 ± 2 °C, até atingirem os teores de água de 17,6; 13,6; 11,1; 8,7; 5,3 (% b.s). Após a secagem foram determinadas as isotermas de dessorção pelo método estático indireto. A atividade de água (Aw) foi determinada sob diferentes temperaturas sendo os aquênios acondicionados em câmara B.O.D., regulada a 10, 20, 30 e 40 °C; aos dados de teor de água de equilíbrio foram ajustados a diferentes modelos matemáticos por meio da análise de regressão não linear, pelo método Gauss-Newton. O modelo Copace foi o que melhor representou a higroscopicidade dos aquênios de cajuzinho-do-cerrado enquanto os valores de calor isostérico integral de dessorção dos aquênios de cajuzinho-do-cerrado para a faixa de teor de água de 4,51 a 13,40 (% b.s.) variaram de 2734,82 a 2548,49 kJ kg-1.

The aeration of seeds with artificially cooled air and their storage in big-bag packages aim to lengthen the shelf life while maintaining the quality. Thus, the objective was to study the effects of cooling before storage on germination and vigor of soybean seeds stored in trifoliate kraft paper bag and big bag in non-air-conditioned environment. Seeds of soybean cultivar NA 7337 RR were mechanically harvested in March 2013, holding an average moisture content of 18% w.b. In June, 16,000 kg of seeds were processed and cooled to 18 °C. Equal amount of non-cooled seeds was used as a control. Equally divided in kraft paper and in big bags, and combining cooling and packaging, the seeds were stored for three months and analyzed for moisture content, germination and vigor. Cooling to room temperature and different packaging types had similar effects on seed quality. Big bags packing showed better efficiency in retaining the moisture content of cooled seeds. No direct effects of cooling could be identified prior to storage on the germination and vigor of soybean seeds.

RESUMO Objetivou-se, nesta pesquisa, avaliar o efeito do uso do herbicida saflufenacil como dessecante em pré-colheita e do armazenamento sobre a qualidade fisiológica e sanitária de sementes de feijão-azuki. Foram testadas seis doses do herbicida saflufenacil (0, 50, 75, 100, 150 e 200 g a.i. ha-1) e duas épocas de avaliação da qualidade das sementes: colheita e seis meses após a colheita. A aplicação do dessecante ocorreu na maturidade fisiológica do feijoeiro azuki e as sementes colhidas foram armazenadas em sacos de papel (Kraft) em ambiente natural, a 25,4 ± 3 ºC de temperatura e 67,3 ± 3% umidade relativa. O saflufenacil pode ser utilizado até a dose de 65 g a.i. ha-1 sem prejudicar a qualidade fisiológica das sementes. O armazenamento provocou queda na percentagem de germinação, aumento no número de plântulas anormais e redução no tamanho e da massa seca das plântulas. A dessecação em pré-colheita e o armazenamento reduzem a infestação Cladosporium, Fusarium, e Rizhopus nas sementes de feijão-azuki. ABSTRACT The objective of this study was to evaluate the effect of using the herbicide saflufenacil desiccant pre-harvest and storage on the physiological and sanitary quality of azuki bean seeds. Six doses of saflufenacil herbicide (0, 50, 75, 100, 150 and 200 g a.i. ha-1) were tested and two evaluation periods of seed quality: harvest and six months after harvest. The desiccant application occurred at physiological maturity of azuki bean and seeds were stored in paper bags (kraft) under natural conditions - 25.4 ± 3 °C temperature and 67.3 ± 3% relative humidity. The saflufenacil may be used up to a dose of 65 g a.i. ha-1, without harming the physiological seed quality. The storage caused a drop in the percentage of germination, increase in the number of abnormal seedlings and reduction in size and dry mass of seedlings. Desiccation pre-harvest and storage reduces the infestation of Cladosporium, Fusarium and Rizhopus on the azuki bean seed.

The aim of this study was to assess the drying behavior and quality of crambe fruit seeds dried with natural air and submitted to different airflows in stationary dryers. Dryings were carried out in July and September 2014. The experiment consisted of three treatments of drying the crambe fruits with natural air in stationary dryers with airflows of 10.08, 15.05, and 25.03 m3 min−1 t−1 and a control treatment composed of crambe fruits with an initial moisture content without going through the drying process. After drying, tests of moisture content, germination, germination rate index, and electrical conductivity were performed in order to compare the treatments. The data were submitted to analysis of variance and mean comparison by the Tukey's test at 5% significance. Among the airflows used in the experiment in both natural air dryings in July and September, no interference was observed for crambe fruit quality. Drying carried out in September was faster and showed a lower expenditure and cost of electricity when compared to that performed in July, which is due to better climatic conditions. No difference was observed in the drying times between airflows, but the drying with natural air using an airflow of 15.05 m3 min−1 t−1 was more profitable. RESUMO O objetivo nesse trabalho foi avaliar o comportamento da secagem e a qualidade das sementes secas com ar natural em frutos de crambe submetidos a diferentes fluxos de ar em secadores estacionários. As secagens foram realizadas em dois períodos, uma em julho e outra em setembro do ano de 2014. O experimento compreendeu três tratamentos "A", "B" e "C" que consistiram na secagem dos frutos de crambe com ar natural em secador estacionário com fluxos de ar de 10,08 m3 min-1 ton-1; 15,05 m3 min-1 ton-1; 25,03 m3 min-1 ton-1, respectivamente e uma testemunha "T" composto por frutos de crambe com teor de água inicial sem passar pelo processo de secagem. Após as secagens, foram realizados testes de teor de água, germinação, índice de velocidade de germinação e condutividade elétrica para comparação dos tratamentos. Os dados obtidos foram submetidos à análise de variância e comparação de médias pelo teste de Tukey a 5% de significância. Dentre os fluxos de ar utilizados no experimento em ambas as secagens com ar natural nos meses de julho e setembro, não houve interferência na qualidade dos frutos de crambe. A secagem realizada no mês de setembro foi mais rápida e apresentou menor gasto e custo de energia elétrica quando comparada com a secagem realizada no mês de julho devido às melhores condições climáticas. Não houve diferença no tempo de secagem entre os fluxos de ar utilizados, porém, a secagem com ar natural utilizando o fluxo de ar de 15,05 m3 min-1 ton-1 mostrou ser mais rentável.

This study aimed to verify the influence of moisture content on the values of maximum compressive strength, proportional deformity modulus, elastic coefficients d, e, and f beyond the tangent values, and maximum grain drying of crambe (Crambe abyssinica Hochst) under compression in natural resting position. Crambe grains with moisture contents ranging from 0.1547 to 0.0482 decimal db were dried at 40°C and uniaxially compressed between two parallel plates in the natural rest position. The gravimetric method was used to monitor reduction in moisture content during drying (weight loss). It was concluded that the compression force required to deform the crambe grains decreases as the moisture content increases. The proportional deformity modulus increases as the deformation decreases, yielding values between (0.09-0.27)×102MPa. Sigmoidal model described by Taylor series adequately represents the compression resistance of crambe grains in the natural rest position with moisture content lower than 0.0813db. RESUMO: Neste trabalho objetivou-se verificar a influência do teor de água nos valores da força máxima de compressão, módulo proporcional de deformidade, coeficientes elásticos d, e, f, além dos valores da tangente e secante máximas nos grãos de crambe (Crambe abyssinica Hochst), submetidos à compressão na posição natural de repouso. Os grãos de crambe, utilizados com teores de água entre 0,1547 e 0,0482 (decimal b.s.), foram secos nas temperaturas de 40°C e comprimidos uniaxialmente entre duas placas paralelas, na posição natural de repouso, cuja redução do teor de água ao longo da secagem foi acompanhada pelo método gravimétrico (perda de massa). A força de compressão necessária para deformar os grãos de crambe diminui com o aumento do teor de água. O módulo proporcional de deformidade aumenta com a redução da deformação, obtendo-se valores entre 0,09 e 0,27 (x 102MPa), em que o modelo sigmoidal, descrito por meio da série de Taylor, representa adequadamente a resistência dos grãos de crambe à compressão na posição natural de repouso, para os teores de água menores que 0,0813 (b.s.)

RESUMOA higroscopicidade de sementes fornece informações essenciais para otimização de processos de secagem, armazenamento e desenvolvimento de embalagens. O objetivo neste trabalho foi determinar as isotermas de dessorção das sementes de pimenta (Capsicum chinense L.), variedade Cabacinha, para diferentes condições de temperatura e atividade de água utilizando-se o método estático indireto, sendo a atividade de água (aw) determinada por meio do equipamento Hygropalm Model Aw1. Aos dados experimentais foram ajustados modelos matemáticos frequentemente utilizados para representação da higroscopicidade de produtos agrícolas. Para uma atividade de água constante o aumento da temperatura reduz o teor de água de equilíbrio higroscópico das sementes de pimenta. As isotermas de dessorção apresentam formato sigmoidal do tipo II. Os modelos de Cavalcanti Mata, Chen Clayton, Chung Pfost, Chung Pfost Modificado, Henderson e Henderson Modificado são adequados para representar a higroscopicidade das sementes de pimenta Cabacinha para a faixa de temperatura de 10 a 40 °C e atividade de água de 0,213 a 0,975.

Objetivou-se, neste trabalho, avaliar o efeito de diferentes embalagens, ambientes e do tempo de armazenamento na qualidade de sementes de crambe. O crambe, com teor de água de 4,63% (b.u.), foi embalado em garrafas de polietileno de alta densidade (PEAD), em garrafas reutilizadas de polietileno tereftalato (PET) e em embalagens laminadas as quais foram armazenadas nos ambientes: refrigerado a 10 ± 1,19 °C e 34,84 ± 4,09% de umidade relativa (UR) e natural a 24,81 ± 1,82 °C e 54,93 ± 12,77% de umidade relativa (AN). Avaliaram-se, durante nove meses, o teor de óleo e de proteína bruta, os índices de acidez, peróxido e iodo, pH e acidez em álcool solúvel. As sementes acondicionadas em embalagem laminada no AN apresentaram maior teor de proteína bruta no 3° mês e as em AR, maiores índices de peróxido, nos 3° e 6° meses. Em AR, as sementes em embalagens de PEAD apresentaram menor acidez em álcool solúvel. Os teores de proteína bruta e de óleo diminuíram durante o armazenamento, o índice de peróxido e o pH aumentaram e o índice de iodo apresentou variação nos valores. No final do armazenamento os valores de acidez em álcool solúvel eram semelhantes aos do início. O índice de acidez não sofreu interferência das variáveis estudadas. The aim of this study was to evaluate the effect of different packaging, environment and storage time on the chemical quality of crambe seeds. Crambe seeds, with a water content of 4.63% (dry basis), were packed into high density polyethylene (HDPE), reused polyethylene terephthalate (PET) bottles and laminated packages, which were stored in two different environments: refrigerated air (RA) at 10 ± 1.19 °C and 34.84 ± 4.09% relative humidity (RH) and natural air (AN) at 24.81 ± 1.82 °C and 54.93 ± 12.77 % RH. For nine months, the oil and crude protein content, acidity index, peroxide and iodine level, pH, and alcohol-soluble acidity were evaluated. Seeds in laminated packages stored in AN showed higher crude protein content after 3rd month, and in AR, there were higher levels of peroxide after 3rd and 6th months. In AR, the seeds in HDPE packaging showed lower alcohol-soluble acidity. Crude protein and oil content decreased during storage, peroxide level and pH increased and iodine level varied. At the end of storage, the alcohol-soluble acidity returned to base line values. The acidity level was not affected by the changes in the variables studied.

Objetivou-se, neste trabalho, avaliar a qualidade fisiológica das sementes de crambe em diferentes condições de armazenamento, durante nove meses. O crambe com teor de água de 4,63% base úmida foi acondicionado nas embalagens laminada, polietileno tereftalato (PET) e polietileno de alta densidade (PEAD), as quais foram armazenadas nos ambientes: refrigerado, a 10 ± 1,19 °C e 34,84 ± 4,09% UR e natural, a 24,81 ± 1,82 °C e 54,93 ± 12,77% UR. O delineamento utilizado foi o inteiramente casualizado em esquema fatorial triplo (3 x 2 x 4) com três repetições. Os dados foram analisados por meio de análise de variância e regressão. O ambiente natural e a embalagem PET são os que melhor se apresentam para manter a qualidade fisiológica das sementes de crambe por até seis meses de armazenamento. O ambiente natural preserva o vigor de sementes e promove superação da dormência primária logo no terceiro mês de armazenamento. O ambiente refrigerado a 10 °C não é recomendado para o armazenamento das sementes de crambe. The present study aimed to evaluate the physiological quality of seeds of crambe in different storage conditions for nine months. The crambe with moisture content of 4.63% (wet basis) was placed in the packages laminated, PET and HDPE, which were stored in environments: refrigerated at 10 ± 1.19 °C and 34.84 ± 4.09% relative humidity (RH) and natural at 24.81 ± 1.82 °C and 54.93 ± 12.77% RH. The completely randomized design in triple factorial (3 x 2 x 4) with three replications was used. Data were analysed by analysis of variance and regression. The natural environment and packaging PET containers is best to maintain seed quality of crambe for up to six months of storage. The natural environment preserves the seed vigor and promotes overcome primary dormancy as early as the third month of storage. The refrigerated environment at 10 °C is not recommended for storage of seeds of crambe.

Objetivou-se, com este trabalho, analisar a qualidade fisiológica das sementes de sorgo sacarino submetidas à secagem em diferentes condições de ar. A secagem do sorgo sacarino foi realizada mantendo-se as temperaturas controladas de 40, 55, 70, 85 e 100 °C e umidades relativas de 28,4; 18,6; 12,2; 7,3 e 3,1%, durante os períodos de 3,0; 1,75; 1,42; 1,08 e 0,83 h, respectivamente. Depois da secagem as sementes foram submetidas às análises de condutividade elétrica, porcentagem de germinação, primeira contagem da germinação, índice de velocidade de germinação (IVG), porcentagem de emergência, primeira contagem da emergência e índice de velocidade de emergência (IVE). Constata-se que o aumento da temperatura do ar de secagem promove maior danificação nas sementes, pelo aumento da condutividade elétrica da solução. A porcentagem de germinação, IVG, porcentagem de emergência e o IVE, tiveram seus valores reduzidos pelo incremento de temperatura. Conclui-se que a qualidade fisiológica das sementes de sorgo sacarino é afetada pela temperatura do ar de secagem e que as temperaturas mais elevadas promovem maiores danos às sementes podendo ser realizada a secagem até a temperatura do ar de 55 °C. The aim of the study was to analyse the physiological quality of sweet sorghum seeds dried at different conditions of air. Drying of sweet sorghum seeds was performed at controlled air temperatures of 40, 55, 70, 85 and 100 °C and relative humidity of 28.4, 18.6, 12.2, 7.3 and 3.1%, during 3.0; 1.75; 1.42; 1.08 e 0.83 h, respectively. The seeds after drying were subjected to analysis of electrical conductivity, germination, first count of germination, germination speed index (GSI), germination percentage, emergence and emergence rate index (ERI). It was found that increasing the temperature of the drying air promotes greater damage to the seeds by increasing the electrical conductivity of the solution. The percentage of germination, GSI, emergence percentage and ERI were reduced with increase in temperature. It is concluded that the seed quality of sweet sorghum is affected by drying air temperature, and that higher temperatures promote greater damage to the seed; drying can be performed until the air temperature of 55 °C.

Objetivou-se, com este trabalho, avaliar o vigor das sementes de soja durante as etapas do beneficiamento e ao longo do armazenamento. O experimento foi desenvolvido no Instituto Federal Goiano, Câmpus Rio Verde, e na empresa Sementes Goiás. Utilizou-se o delineamento inteiramente casualizado, segundo o esquema fatorial triplo 6 x 2 x 4 (seis etapas do beneficiamento, duas condições de armazenamento e quatro tempos de armazenamento) com três repetições. Foram utilizadas sementes de soja Glycine max (L.) Merrill, cultivar BMX Potência RR. As sementes foram avaliadas ao longo do armazenamento (0, 3, 6 e 9 meses) quanto ao teor de água, teste de tetrazólio e emergência em areia. Os dados foram analisados por meio de análise de variância e regressão adotando-se o nível de 0,05 de significância. Concluiu-se que o beneficiamento das sementes de soja não afetou a qualidade fisiológica das sementes e a cultivar BMX Potência RR apresentou qualidade fisiológica superior pelo teste tetrazólio (acima de 80%) apesar do vigor, germinação e emergência se apresentarem altos durante nove meses de armazenamento e o comprimento de raiz e de plantas jovens normais foi influenciado negativamente pelo tempo. Em câmara climatizada as sementes apresentam maior viabilidade dependendo do teor de água do produto. The aim of the present study was to evaluate the effect of soybean seeds during processing and storage. The experiment was conducted at Federal Institute of Goiás, Campus Rio Verde and the company Seeds Goiás. A completely randomized design was used according to the triple factorial scheme 6 x 2 x 4 (six stages of processing, two storage conditions and four storage times), with three replications. Seeds of soybean (Glycine max L.) Merrill cultivar BMX Potência RR were used. The seeds were evaluated during storage (0, 3, 6 and 9 months) as to moisture content, tetrazolium and emergence in sand. Data were analysed by analysis of variance and regression, adopting the 0.05 level of significance. It was concluded that: the processing of soybean seeds did not affect the physiological quality of soybean seeds and cultivar BMX Potência RR showed higher physiological quality by tetrazolium test (above 80%); although the vigor, germination and emergence remained high for nine months storage, the root length and number of normal young seedlings were negatively influenced by the weather. In climate chamber seeds showed higher viability depending on the moisture content of the product.

Propôs-se, com este trabalho, determinar as isotermas de dessorção das sementes de nabo forrageiro e ajustar modelos matemáticos aos dados experimentais obtidos pelos métodos estático e dinâmico e verificar a possibilidade de utilização de um único modelo para ambos os métodos. Os teores de água de equilíbrio foram determinados pelo método dinâmico para as temperaturas de 25, 30, 35 e 40 ºC e atividades de água para cada temperatura, entre 0,27 a 0,82. No método estático foram utilizados dessecadores contendo as amostras e soluções salinas saturadas que foram colocadas em câmaras B.O.D. mantidas nas mesmas temperaturas. Aos dados experimentais foram ajustados modelos matemáticos disponíveis na literatura. Segundo os parâmetros estatísticos de análise, o modelo de Copace foi o que descreveu melhor a higroscopicidade das sementes de nabo forrageiro obtida pelo método dinâmico e, para o método estático, os modelos de Sigma Copace, Oswin, Halsey Modificado e Copace foram os que melhor representaram a higroscopicidade das sementes de nabo forrageiro. Segundo a técnica de identidade de modelos, é possível ajustar uma única equação de Copace aos dados experimentais para os dois métodos analisados. This study aimed to determine the desorption isotherms of radish seeds and adjust mathematical models to experimental data obtained by static and dynamic methods, and to verify the possibility of using a single model for both methods. The equilibrium moisture contents were determined by dynamic method at temperatures of 25, 30, 35, and 40 ºC and water activity for each temperature from 0.27 to 0.82. In the static method desiccators were used containing saturated salt solutions and samples that were placed in B.O.D (Biological Oxygen Demand) chambers maintained at the same temperatures. Mathematical models available in the literature were adjusted to experimental data. According to statistical analysis parameters, Copace model was the one that best described the hygroscopicity of radish seeds obtained by the dynamic method; for the static models, Copace Sigma, Oswin, Modified Halsey and Copace were the ones that best represented hygroscopicity of radish seeds. According to the technique of model identity, it is possible to adjust a single Copace equation to the experimental data for both analyzed methods.

Sorption isotherms are of great importance in post-harvest procedures, especially for predicting drying and storage, which help to establish the final moisture content of the product under certain environmental condition. Hysteresis is a phenomenon that occurs due to the difference between adsorption and desorption curves, which aids the evaluation of chemical and microbiological deteriorations, indicating the stability of stored products. Moisture sorption isotherms of castor beans were determined and hysteresis was analyzed. Static gravimetric technique at different temperatures (25, 35, 45 and 55 ± 1 °C) was used. Saturated salt solutions in the range of 37-87% ± 2% were utilized to create the required controlled relative humidity environment. Equilibrium moisture content data were correlated by different mathematical models and the Modified Halsey model presented good adjustment for the data, according to statistical procedures. Hysteresis between adsorption and desorption isotherms is present over the range of 0.2-0.9 of water activity, regardless of the temperature. This phenomenon decreases with temperature increase. RESUMO As isotermas de sorção são de grande importância em procedimentos pós-colheita de produtos agrícolas, em especial para predizer os processos de secagem e armazenamento os quais auxiliam a estabelecer o teor de água final no produto em determinada condição ambiental. A histerese é um fenômeno que ocorre em virtude da diferença entre as curvas de adsorção e dessorção que auxilia a avaliação de deteriorações químicas e microbiológicas indicando a estabilidade de produtos armazenados. Isotermas de sorção de grãos de mamona foram determinadas e a histerese analisada. Utilizou-se a técnica de gravimetria estática em diferentes temperaturas (25, 35, 45 e 55 ± 1 °C). Soluções salinas saturadas na faixa de 37-87% ± 2% foram utilizadas para criar o requerido ambiente controlado de umidade relativa. Os dados de teor de água de equilíbrio foram correlacionados com diferentes modelos matemáticos e o modelo de Halsey Modificado apresentou bom ajuste aos dados, de acordo com procedimentos estatísticos. Histerese entre as isotermas de adsorção e dessorção está presente na faixa de 0,2-0,9 de atividade de água independentemente da temperatura; este fenômeno decresce com o aumento da temperatura.

The objective was to determine water sorption isotherms of diaspores of pequi fruits in order to obtain information on the amount of water that this product desorbs at the temperatures of 10, 20, 30 and 40 °C and water activities from 0.20 to 0.89, adjusting different mathematical models to experimental data, and to determine its latent heat and isosteric heat. The equilibrium moisture content was obtained through the indirect static method, using the device Hygropalm Model Aw 1. The Modified Henderson model was the one that best fitted the data and was selected to predict the equilibrium moisture content of pequi diaspore. It was observed that the higher the temperature for the same equilibrium moisture content (% d.b.), the higher the water activity values. As temperature values increased, there was a reduction in the vaporization latent heat of the product. Isosteric heat values of diaspores of pequi fruits in the moisture content range of 4.02 to 16.63 (% d.b.) varied from 2,776.49 to 2,558.39 kJ kg-1. RESUMO Objetivou-se, com este trabalho, determinar as isotermas de dessorção de água de diásporos de pequi a fim de obter informações da quantidade de água que este produto dessorve nas temperaturas de 10, 20, 30, 40 °C e atividades de água entre 0,20 e 0,89, ajustar diferentes modelos matemáticos aos dados experimentais e determinar o calor latente e o calor isostérico. Para obtenção do equilíbrio higroscópico foi utilizado o método estático indireto com uso do equipamento Hygropalm Model Aw 1. O modelo Henderson Modificado foi o que melhor se ajustou aos dados sendo selecionado para predição do equilíbrio higroscópico dos diásporos de pequi. Verificou-se que quanto maior a temperatura para um mesmo teor de água de equilíbrio (% b.s.) maiores são os valores de atividade de água. Com o aumento da temperatura ocorre redução da magnitude do calor latente de vaporização do produto. Os valores de calor isostérico para os diásporos de pequi na faixa de teor de água de 4,02 a 16,63 (% b.s.) variaram de 2.776,49 a 2.558,39 kJ kg-1.

Com base na necessidade de combustíveis que substituam o petróleo, do destaque do pinhão-manso na produção de biodiesel e da necessidade de construção e aperfeiçoamento dos equipamentos utilizados nas fases de colheita e pós-colheita desta cultura objetivou-se, com o presente trabalho, determinar a forma e o tamanho dos frutos de pinhão-manso durante a secagem em cinco condições de ar. Os frutos colhidos manualmente com o teor de água de 4,40 (kg de água por kg de matéria seca) foram submetidos a secagem em estufa com circulação de ar forçada em cinco condições de temperatura, 45, 60, 75, 90 e 105 °C, e umidades relativas de 14,5; 7,4; 3,8; 2,2 e 1,4%, respectivamente, até atingir teor de água de 0,10 ± 0,007 (kg kg-1 de matéria seca). Foram determinados circularidade, esfericidade, volume, área superficial, área projetada e relação superfície-volume, ao longo da secagem. Conclui-se que a redução do teor de água e as condições de secagem alteram a forma e reduzem o tamanho dos frutos de pinhão-manso sendo possível ajustar uma única equação aos dados experimentais do volume e da área superficial dos frutos de pinhão-manso ao longo da secagem, em diversas temperaturas. Due to the need for substitution of fuel oil, the importance of Jatropha for biodiesel and the need for construction and improvements of the equipment used during harvest and postharvest of this crop, this research aimed to determine the shape and the size of Jatropha fruit during drying under five ambient conditions. The fruits harvested manually with moisture content of 4.40 kg kg-1 dry matter were dried in an oven with forced air ventilation in five temperature conditions: 45, 60, 75, 90 and 105 °C and relative humidities of 14.5, 7.4, 3.8, 2.2 and 1.4% respectively, until moisture content of 0.10 ± 0.007 (kg kg-1 dry matter). The roundness, sphericity, volume, surface area, projected area and surface-volume ratio were determined during drying. It is concluded that the reduction of the moisture content and the drying conditions alter the shape and reduce the size of the fruit of Jatropha, being possible to adjust a single equation to the experimental data of volume and surface area of the fruit of Jatropha during drying at different temperatures.

RESUMO O estudo da cinética de secagem é de fundamental importância para a modelagem matemática, a qual tem sido muito usada no projeto e em análise dos processos de transferência de calor e de massa, durante a secagem. Buscou-se, então, avaliar a capacidade de ajuste de nove modelos matemáticos comumente utilizados para descrever o processo de secagem em sementes de crambe (Crambe abyssinica Horts), através de um delineamento inteiramente casualizado com três repetições, em que os tratamentos são constituídos de cinco teores de água (0,11; 0,13; 0,17; 0,25 e 0,28 decimal b.s) e cinco temperaturas do ar de secagem (30; 40; 50; 60 e 70 ºC). Para verificação do ajuste dos modelos estudados fez-se análise de regressão não-linear, pelo método Quasi-Newton. De acordo com os dados obtidos conclui-se que: o modelo da Aproximação por Difusão é o que melhor se ajusta aos dados de secagem obtidos; o aumento da temperatura de secagem promove maior taxa de remoção da água do produto; o coeficiente de difusão apresenta valores da ordem de 0,18 x 10-10 e 3,92 x 10-10 m2 s-1 e a energia de ativação para a difusão líquida foi da ordem de 4,97 kJ mol-1.

Em delineamento inteiramente casualizado com quatro repetições foi realizado um trabalho com o objetivo de determinar o modelo matemático que melhor descreve a secagem de sementes de nabo forrageiro, bem como o coeficiente de difusão e a energia de ativação em diferentes condições de ar. Sementes colhidas com teor de água de 0,36 (decimal b.s.) foram secas até 0,09 (decimal b.s.) em secador experimental com as temperaturas controladas de 30; 40; 50; 60 e 70 °C e umidades relativas de 47,3; 26,2; 12,0; 10,1 e 5,1%, respectivamente. Os dados de coeficiente de difusão foram analisados por meio de análise de variância pelo teste F e regressão, adotando-se o nível de 5% de probabilidade. Conclui-se que dentre os modelos analisados, o que apresentou melhor ajuste para descrever as curvas de secagem do nabo forrageiro foi o de Midilli. O coeficiente de difusão efetivo aumenta com a elevação da temperatura, apresentando valores entre 3,23 x 10-11 e 10,42 x 10-11 m² s-1, para faixa de temperatura de 30 a 70 °C. A relação entre o coeficiente de difusão e a temperatura de secagem pode ser descrita pela equação de Arrhenius, que apresenta uma energia de ativação para a difusão líquida no processo de secagem do nabo forrageiro de 24,78 kJ mol-1. A study aimed at determining the best mathematical model to describe the drying of forage-turnip seeds, along with the diffusion coefficient and activation energy under different air-conditions, was carried out in a randomized design with four replications. Seeds were harvested, having a moisture content of 0.36 (decimal bs) and then dried to 0.09 (decimal bs) in an experimental dryer at controlled temperatures of 30; 40; 50; 60 and 70 °C and relative humidities of 47.3; 26.2; 12.0; 10.1 and 5.1%, respectively. The effective coefficient of diffusion was calculated by F-test variance analysis and regression, adopting a 5% level of probability. The conclusion was reached that among the models analyzed, that of Midilli best fit the drying curves of forage-turnip seeds. The effective diffusion coefficient increases with temperature, with values of between 3.23 x 10-11 and 10.42 x 10-11 m² s-1 for a temperature range of from 30 to 70 °C. The relationship between the coefficient of diffusion and drying temperature can be described by the Arrhenius equation which gives an activation energy of 24.78 kJ mol-1 for liquid diffusion in the drying process of forage-turnip seeds.

This study was carried out to evaluate the effect of the mechanical damage on popcorn kernels under controlled impacts upon the popcorn quality during storage, as well as to analyse the electrical conductivity test as a simple, fast and low-cost alternative for evaluating the commercial quality of the popcorn. The kernels were manually harvested and husked, then dried in the shade until reaching ±13% wet basis and subjected to the mechanical damage, by using different impact times with the Stein Breakage Tester device (CK2-M model). Afterwards, they were stored in low-density polypropylene sacks over a 6 month period under uncontrolled environmental conditions. The quality of the kernels were analysed at the beginning of the experiment and every subsequent month by applying the popping expansion capacity test. The mechanical damage level was evaluated by applying the electrical conductivity test. The results indicate that the popping expansion capacity is considerably decreased as the impact time is increased, with a slight increase in these values for all treatments during the storage period. In relation to the electrical conductivity test, the values increased as the impact time and the storage period increased, indicating that the damage to the kernel pericarp causes the integrity loss with a lower expansion of the kernels and higher electrolytic leaching of the cellular kernel solutes to the deionised water solution. Therefore, an equation was adjusted to the data of the popping expansion capacity as a function of the electrical conductivity and demonstrated the potential of the electrical conductivity test as a basis for estimating the popcorn quality.

Diante da importância do conhecimento da higroscopicidade e do calor isosterico para as operacoes de secagem e armazenamento, objetivou-se neste trabalho determinar as isotermas de dessorcao de sementes de Buchenavia capitata (Vahl) Eichler, bem como ajustar diferentes modelos matematicos aos dados experimentais, selecionando aquele que melhor representa o fenomeno e, assim, utiliza-lo para determinar o calor isosterico de dessorcao. Para obtencao do teor de agua de equilibrio higroscopico utilizaram-se as sementes de B. capitata com teor de agua inicial de 13,16 ± 0,17% base seca (b.s.). Para obtencao das isotermas de dessorcao das sementes, utilizou-se o metodo estatico indireto, sendo a atividade de agua (aw) determinada por meio do equipamento Hygropalm Model Aw 1. Para o controle da temperatura utilizou-se uma câmara tipo B.O.D., regulada a 10; 20; 30 e 40 °C. Aos dados experimentais foram ajustados os modelos matematicos frequentemente utilizados para representacao da higroscopicidade de produtos vegetais. O teor de agua de equilibrio higroscopico das sementes de Buchenavia capitata (Vahl) Eichler e diretamente proporcional a atividade de agua e decresce com o aumento de temperatura para um mesmo valor de umidade relativa de equilibrio. O modelo matematico de Copace e o que melhor representa a higroscopicidade de sementes de B. capitata nas temperaturas e nas atividades de agua estudadas. O calor isosterico de sementes de B. capitata aumenta com a diminuicao do teor de agua de equilibrio, sendo necessaria maior quantidade de energia para retirar a agua.

Objetivou-se, no presente trabalho, avaliar a eficácia de um equipamento redutor de inóculo (ERI) na preservação da qualidade sanitária de sementes de feijão (Phaseolus vulgaris L.) durante o armazenamento em estruturas herméticas com circulação de ar forçado. A presença de inóculo no ar foi monitorada a partir da exposição de placas de Petri com meio de cultura BDA salino, contando-se o número de unidades formadoras de colônias (UFC) dos fungos Aspergillus spp. e Penicillium spp. As análises sanitárias das sementes foram realizada pelo método do papel de filtro (Blotter test), calculando-se o índice de ocorrência de Aspergillus spp. e Penicillium spp. Durante o período de armazenamento, houve um aumento na incidência de fungos nas sementes, independente da presença dos ERI. Nas amostragens realizadas na entrada da caixa com a presença dos ERI, não foram encontradas unidades formadoras de colônias. Com o aumento do fluxo de ar utilizado no sistema, notou-se que este efeito foi transferido para a saída da caixa. Nas condições especificadas, os ERI foram incapazes de controlar os fungos de armazenamento, Aspergillus spp e Penicillium spp, nas sementes de feijão, porém foram eficazes no controle dos seus esporos presentes no ar. The objective of the present work was to evaluate the efficiency of inoculum reducing equipment (IRE) in the maintenance of quality of bean seeds during storage in hermetic structures with circulation of forced air. The inoculum's presence in the air was monitored by the exposition of Petri dishes with culture medium (saline BDA) by counting the number of colonies units of Aspergillus and Penicillium. The quality analysis of seeds were performed by the blotter test. The occurrence index was calculated for Aspergillus spp and Penicillium spp. The fungal occurrence increased during the storage period, in spite of the IRE presence. Fungal colonies were not found in the air samples collected at the box entrance, holding IRE. As the airflow used in the system was increased, the effect of the equipment has been moved to the box exit. For the conditions of this work, the IRE were not capable to control the storage fungi in the seeds, however were efficient to control the spores in the air.

O presente trabalho foi realizado com o objetivo de se avaliar o efeito da variação do teor de água nas propriedades físicas dos grãos de trigo e ajustar diferentes modelos matemáticos aos valores experimentais, em função do teor de água do produto; além disso, analisaram-se duas metodologias de determinação da massa específica aparente e da massa específica real. Com base nos resultados obtidos, concluiu-se que a redução do teor de água influencia as propriedades físicas dos grãos de trigo, provocando a diminuição da porosidade, o aumento da massa específica aparente e da massa específica real. Outrossim, os valores das massas específicas real e aparente, calculados a partir da composição química dos grãos de trigo, são inferiores aos valores experimentais; contudo, as diferenças entre os valores obtidos pelas duas metodologias diminuem com a redução do teor de água do produto. O modelo de Bala & Woods adaptado é o que melhor se ajusta aos dados experimentais de contração volumétrica do grão e da massa de grãos de trigo. Embora tenha ocorrido contração de volume dos grãos de trigo, sua forma (esfericidade e circularidade) não varia durante o processo de secagem, para a faixa de umidade estudada. The objectives of this work was to evaluate the effect of variation of water content on the physical properties of wheat grain and to adjust different mathematical models to the obtained experimental values as a function of moisture content. Also two different methodologies for determining bulk density and the real density were analysed. Based on the obtained results it may be concluded that the reduction of the moisture content affects the physical properties of wheat grain promoting the decrease of porosity and increase of both the bulk density and the specific gravity. Also the wheat grain bulk density and specific and real gravity values found through the chemical composition of grain were lower than the experimental data. However, the differences in values found between the two methodologies decreased as the moisture content decreases. The adapted Bala & Woods model fits best the individual wheat grain shrinkage as well as the bulk grain volume shrinkage. The grain shape (sphericity and circularity) did not vary for the moisture content range in this experiment.

This study aimed to determine and evaluate the thermodynamic properties of crambe fruit at different equilibrium moisture contents. The dynamic-gravimetric method was used to collect experimental data. Crambe fruits with an initial moisture content of approximately 26% db (dry basis) were used. The thin-layer desorption of the product was conducted at different controlled temperatures (25, 30, 35, 40, and 45°C) and at water activity levels ranging from 0.10 to 0.89 until the product reached the equilibrium moisture content at the specified air condition. In conclusion, the thermodynamic properties of crambe fruit are affected by temperature and moisture content. The isokinetic theory is valid for the desorption process, which is controlled by enthalpy, and the Gibbs free energy is positive at all of the tested temperatures, which indicates that water desorption is not a spontaneous process.

Propôs-se, neste trabalho, avaliar a qualidade fisiológica das sementes de soja ao longo do armazenamento durante 180 dias em diferentes teores de água e em duas condições de temperatura. Foram utilizadas sementes de soja, cultivar CD 242 RR com teores de água iniciais de 12, 13 e 14% (b.u.). As sementes foram adquiridas com o teor de água de 11,0% (b.u.); em seguida, foram umedecidas em câmara BOD a 20 ºC e 85% de umidade relativa, homogeneizadas e acondicionadas em sacos plásticos de polipropileno; as embalagens foram mantidas em dois ambientes distintos. Com vista à avaliação das sementes ao longo do armazenamento foram realizadas as análises de teor de água, germinação, primeira contagem da germinação, índice de velocidade de germinação e condutividade elétrica. O experimento foi conduzido no delineamento inteiramente casualizado, segundo o esquema fatorial triplo 2 x 4 x 3 (duas condições de armazenamento, quatro tempos de armazenamento e três teores de água), com três repetições. O teor de água inicial influencia na qualidade das sementes de soja durante o armazenamento. O ambiente climatizado (20 ºC) proporciona melhores resultados em todas as características estudadas. The objective of this study was to evaluate the physiological quality of the soybean seed during storage for 180 days at different moisture contents and two temperatures. Seeds of soybean, cultivar CD 242RR with initial moisture contents of 12, 13 and 14.0% (w.b.) were used. The seeds were acquired with a moisture content of 11.0% (w.b.), then were soaked in growth chamber at 20 ºC and 85% relative humidity, homogenized and packed in polypropylene bags. The vials were kept in two different environments. For the evaluation of seeds during storage analysis of moisture content, germination, speed of germination and electrical conductivity were conducted. The experiment was conducted in a completely randomized design, according to the triple factorial 2x4x3 (two storage conditions, four storage times and three levels of moisture) with three replications. The initial moisture content influenced the quality of soybean seeds during storage. The air-conditioned environment (20 ºC) provided better results in all the studied traits.

The jatropha has emerged on the world scene as a promising plant for the production of biodiesel. However, this crop still lacks the development of specific equipment for its processing, particularly post-harvest. Therefore, the aim of this work was to fit different mathematical models to experimental data obtained while drying jatropha fruits, and to recommend the one that best represents the facts. Jatropha fruit with a moisture content of 4.4 (kg moisture kg-1 dry matter) were subjected to drying in a greenhouse with forced air-ventilation at five temperature conditions: 45; 60; 75; 90 and 10 ºC and relative humidities of 14.5; 7.4; 3.8; 2.2 and 1.4%, respectively, until reaching a moisture content of 0.10 ± 0.005 (kg moisture kg-1 dry matter),with three replications. Ten mathematical models, used to represent the drying of agricultural products, were adjusted to fit the experimental drying data. The models were analyzed using the coefficient of determination, chi-square, mean relative error, mean estimated error and residual distribution. It can be concluded that the Page model satisfactorily describes the kinetics of jatropha-fruit drying, at temperatures of 60; 75; 90 and 105 ºC. However, drying at a temperature of 45 ºC produced different behavior, making necessary the adjustment of a new model to describe the phenomenon. O pinhão-manso tem se destacado no cenário mundial como planta promissora para a produção de biodiesel. No entanto, esta cultura ainda carece do desenvolvimento de equipamentos específicos para o seu processamento, principalmente na fase pós-colheita. Sendo assim, objetivou-se com o presente trabalho ajustar diferentes modelos matemáticos aos dados experimentais obtidos na secagem dos frutos de pinhão-manso e recomendar aquele que melhor representa o fenômeno. Os frutos de pinhão-manso com o teor de água de 4,40 (kg de água kg-1 de matéria seca), foram submetidos à secagem em estufa com ventilação de ar forçada em cinco condições de temperatura: 45; 60; 75; 90 e 105 ºC e umidades relativas de 14,5; 7,4; 3,8; 2,2 e 1,4%, respectivamente, até atingirem o teor de água de 0,10 ± 0,005 (kg de água kg-1 de matéria seca) em três repetições. Aos dados experimentais da secagem foram ajustados dez modelos matemáticos utilizados para representação da secagem dos produtos agrícolas. Os modelos foram analisados por meio do coeficiente de determinação, do qui-quadrado, do erro médio relativo, do erro médio estimado e da distribuição de resíduos. Conclui-se que, o modelo de Page descreve satisfatoriamente a cinética de secagem dos frutos de pinhão-manso nas temperaturas de 60; 75; 90 e 105 ºC. No entanto, para a secagem na temperatura de 45 ºC ocorreu um comportamento diferenciado sendo necessário um ajuste de um novo modelo para a descrição do fenômeno.

Neste trabalho objetivou-se determinar as isotermas de sorção dos frutos de crambe e obter os valores do calor isostérico de dessorção em função do teor de água de equilíbrio. Para obtenção do teor de água de equilíbrio higroscópico utilizaram-se os frutos de crambe com teor de água inicial de 26,0 (% base seca) e o método estático-gravimétrico e, para cada repetição, foram colocados 10 g de frutos envolvidos por um tecido permeável para permitir o contato do ar com o produto e colocados no interior dos dessecadores enquanto para o controle da umidade relativa no interior dos dessecadores foram utilizadas soluções saturadas. Os dessecadores foram colocados em câmara incubadora tipo B.O.D. regulada para as temperaturas de 25, 30, 35 e 40 °C. O teor de água de equilíbrio higroscópico dos frutos de crambe é diretamente proporcional à atividade de água e decresce com o aumento de temperatura, para um mesmo valor de umidade relativa de equilíbrio. Baseando-se em parâmetros estatísticos os modelos de Copace e Oswin Modificado são os que melhor representam a higroscopicidade dos frutos de crambe quando comparados com os demais modelos testados. O calor isostérico aumenta com a diminuição do teor de água de equilíbrio sendo necessária uma quantidade maior de energia para retirar a água dos frutos de crambe. This study aimed to adjust different mathematical models to experimental data of hygroscopicity of crambe fruits, selecting one that best represented the phenomenon, and obtain the values of the isosteric heat of desorption as a function of equilibrium moisture content. To obtain an equilibrium moisture content, crambe fruit was used with an initial moisture content of 26.0% (dry basis) and static gravimetric method. For each replicate 10 g of fruit were placed surrounded by a permeable fabric to permit air contact with the product and placed within the desiccators. To control the relative humidity inside the desiccators, saturated solutions were used. The desiccators were placed in incubator B.O.D., adjusted to temperatures of 25, 30, 35 and 40 °C. The equilibrium moisture content of crambe fruits is directly proportional to water activity and decreases with increasing temperature for the same value of equilibrium relative humidity. Based on statistical parameters, the models of Copace and Modified Oswin are those that best represent the hygroscopicity of crambe fruits compared to other tested models. The isosteric heat increases with decrease in equilibrium moisture content and requires a larger amount of energy to remove water from the crambe fruit.

O estudo das propriedades termodinâmicas propor-ciona o conhecimento da afinidade do sorvente pela água e da espontaneidade do processo de sorção, sendo importante para projetar equipamentos de secagem. Este trabalho visou a determinar e avaliar as propriedades termodinâmicas, para diferentes teores de água de equilíbrio em grãos de milho, utilizando-se o método estático indireto. O experimento foi desenvolvido em Rio Verde (GO), utilizando-se grãos de milho da cultivar AG 7088, com teor inicial de água de 23,3% (base seca - b.s.), os quais foram submetidos a secagem (40ºC), até atingirem teor de água de 14,4% (b.s.). Concluiu-se que as propriedades termodinâmicas foram influenciadas pelo teor de água, o calor isostérico integral de dessorção aumentou com o decréscimo do teor de água de equilíbrio, o processo de dessorção do milho da cultivar AG 7088 foi controlado pela entalpia e a energia livre de Gibbs foi positiva para as temperaturas estudadas, com aumento ao longo do processo de dessorção, demonstrando ser um processo não espontâneo. The study of thermodynamic properties provides knowledge on the sorbent affinity for water and spontaneity of the sorption process, being important to design drying equipments. This study aimed at determining and evaluating the thermodynamic properties of different equilibrium moisture contents in maize grains, by using the indirect static method. The experiment was conducted in Rio Verde, Goiás State, Brazil, with maize grains (AG 7088 cultivar) presenting an initial moisture content of 23.3% (dry basis - d.b.), which were dried (40ºC) to achieve the moisture content of 14.4% (d.b.). It was observed that the thermodynamic properties were influenced by moisture content, the integral isosteric heat of desorption increased with the decrease in the equilibrium moisture content, the desorption process of the AG 7088 maize cultivar was controlled by enthalpy and the Gibbs free energy was positive for the temperatures evaluated, increasing along the desorption process, showing to be a non-spontaneous process.

Estudos sobre a conservação e exploração de espécies nativas do Cerrado são fundamentais para tecnologias que visem à exploração racional destes produtos. Objetivou-se, neste trabalho, determinar as isotermas de dessorção de sementes de caju-de-árvore-do-cerrado, para diversas condições de temperatura e atividades de água, bem como ajustar diferentes modelos matemáticos aos dados experimentais, selecionando aquele que melhor representa o fenômeno. A higroscopicidade foi determinada pelo método estático-gravimétrico, para temperaturas de 25ºC, 30ºC, 35ºC e 40ºC e atividades de água entre 0,12 e 0,89 (decimal). Observou-se que o teor de água de equilíbrio decresceu com o aumento da temperatura, para uma mesma atividade de água, à semelhança dos produtos higroscópicos. O modelo de Chung-Pfost obteve o maior coeficiente de determinação e menores valores de erro médio relativo, erro médio estimado e Qui-quadrado, sendo selecionado para predição do equilíbrio higroscópico de sementes de caju-de-árvore-do-cerrado. O calor isostérico aumentou com a diminuição do teor de água, ou seja, aumentou a energia necessária para a remoção de água, com valores variando de 4.586,35 kJ kg-1 a 2.572,7 kJ kg-1, na faixa de teor de água de 1,76-6,56 (% b.s.). Studies on conservation and exploitation of the Brazilian Savannah native species are essential to technologies that lead to the rational exploitation of these products. This study aimed at determining the desorption isotherms of Anacardium othonianum seeds for different temperature and water activity conditions, as well as adjusting different mathematical models to the experimental data, by selecting the one that best represents the phenomenon. The hygroscopicity was determined with the aid of the gravity static method, for temperatures of 25ºC, 30ºC, 35ºC and 40ºC and water activity between 0.12 and 0.89 (decimal). It was observed that the equilibrium moisture content decreased while the temperature increased, for the same water activity, similarly to what happens with hygroscopic products. The Chung-Pfost model reached the highest determination coefficient and the lowest values for relative average error, estimated medium error and chi-square test, being the one selected to predict the hygroscopic equilibrium of Anacardium othonianum seeds. The isosteric heat increased, while the moisture content decreased, i.e., it increased the energy required to remove water, varying from 4,586.35 kJ kg-1 to 2,572.7 kJ kg-1, for the moisture content of 1.76-6.56 (d.b. %).

This study was performed to evaluate the physiological quality of Crambe abyssinica Hochst fruits subjected to drying under different treatments with air. The crambe fruits, with moisture content of 21.0 ± 1.3 (% w.b.), were manually collected and dried until their moisture content reached 7.0 ± 1.4 (% w.b.). The crambe fruits were dried with natural air (23°C mean temperature and 60.6% average relative humidity) and seven days after harvest in an experimental dryer with forced ventilation at temperatures of 30, 40, 50, 60 and 70°C and relative humidities of 37.4, 22.3, 14.0, 8.3 and 5.1%, respectively. The evaluation was the percent germination, the germination speed index (GSI), the amount of water absorption and the electrical conductivity. The results of the study showed that increases in the drying temperature decreased the drying time and negatively affected the quality of the fruits. The study's findings for the GSI and for the percent germination showed that the drying temperature of 30°C yielded superior results. The moisture content of the crambe fruits after absorption was higher at the drying temperatures of 23, 40 and 70ºC. In contrast, the electrical conductivity measurement was unaffected by drying at high temperatures. Objetivou-se avaliar a qualidade fisiológica dos frutos de Crambe abissynica, submetidas à secagem em diversas condições de ar. Frutos de crambe foram colhidos manualmente com teor de água de 21,0 ± 1,3 (% b.u) e secas até o teor de 7,0 ± 1,4 (% b.u.). A secagem foi realizada com ar natural (temperatura média de 23ºC e umidade relativa média de 60,6%) e sete dias após a colheita em secador experimental nas temperaturas de 30, 40, 50, 60 e 70°C e umidades relativas de 37,4; 22,3; 14,0; 8,3 e 5,1% respectivamente. A qualidade dos frutos foi avaliada pela porcentagem de germinação, índice de velocidade de germinação (IVG), absorção de água e condutividade elétrica. Com o aumento da temperatura o tempo de secagem reduziu e a qualidade dos frutos foi influenciada negativamente. Para a temperatura de 30ºC o IVG e a porcentagem de germinação foram superiores às demais temperaturas avaliadas. O teor de água dos frutos de crambe depois da absorção de água foi mais elevado para as temperaturas de secagem de 23, 40 e 70ºC. A secagem em temperaturas elevadas não influenciou a condutividade elétrica.

Em sementes armazenadas sob condições adequadas, a velocidade do processo de deterioração pode ser diminuída, permitindo a conservação da viabilidade das mesmas por período mais prolongado do que o obtido em condições naturais. Objetivou-se no presente trabalho avaliar a qualidade dos frutos de Crambe abyssinica armazenados em diferentes condições ambientais. Foram utilizados frutos de crambe com teor de agua de 6% b.u. Os testes de condutividade elétrica, absorção de água, porcentagem de germinação e índice de velocidade de germinação (IVG) foram realizados no início do experimento (0 meses) e a cada 2 meses, durante um ano. O armazenamento foi realizado em três condições distintas: condição ambiente (26 ± 3 ºC; 55 ± 12% Umidade Relativa - UR), câmara refrigerada do tipo B.O.D. (5 ± 1 ºC; 79 ±5 % UR) e câmara climatizada com aparelho de ar condicionado (18 ± 1 ºC; 53 ± 7% UR). A câmara climatizada (18 ± 1 ºC; 53 ± 7% UR) conserva melhor a qualidade dos frutos de crambe em relação à condição ambiente (26 ± 3 ºC; 55 ± 12% UR) e câmara refrigerada do tipo B.O.D. (5 ± 1 ºC; 79 ± 5% UR). O armazenamento dos frutos por doze meses, nos três ambientes analisados, promove a quebra de dormência das sementes. The speed of the deterioration process in seeds stored under proper conditions can be reduced, and seed viability can be maintained for longer than under natural conditions. The aim of this study was to evaluate Crambe abyssinica fruit quality for storage under different environmental conditions. The initial moisture content of crambe seeds was 6% w.b. The electrical conductivity, water absorption, germination and germination speed index (GSI) were determined at the beginning (0 months) and every two months for one year. Seeds were stored under three different conditions: normal environment (26 ± 3 ºC, 55 ± 12% Relative Humidity - RH), refrigerated type B.O.D. (5 ± 1 º C, 79 ± 5% RH) and in a climate chamber with air conditioning (18 ± 1 ºC, 53 ± 7% RH). The climate chamber (18 ± 1 ºC, 53 ± 7% RH) maintains the best crambe fruit quality compared to the normal environment (26 ± 3 ºC, 55 ± 12% RH) and the refrigerated type B.O.D. (5 ± 1 ºC, 79 ± 5% RH). Fruits stored for twelve months in the three environments caused the seed dormancy to breakdown.