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Abstract Generally, medicinal plants are harvested with high amount of water, so it is essential to subject the product to drying as soon as possible to prevent degradation before application. Most compounds from medicinal plants are sensitive to drying processes, so it is important to adjust the drying conditions. The objective of this study was to describe the drying of Rue (Ruta chalepensis L.) leaves, select the models that best fit each drying condition, determine the activation energy and thermodynamic properties of the leaves, and evaluate their quality after drying. Leaves were harvested with moisture content of 3.55 ± 0.05 kg water kg−1 dry matter and subjected to drying at temperatures of 40, 50, 60 and 70 °C. Valcam model showed the best fit to represent the drying kinetics of Rue leaves at temperatures of 40 and 70 °C, and Midilli model proved to be better for the temperatures of 50 and 60 °C. Effective diffusion coefficient increased linearly with the increase in drying air temperature, and the activation energy was 60.58 kJ mol−1. Enthalpy, entropy and Gibbs free energy values ranged from 57.973 to 57.723 kJ mol−1, from − 0.28538 to − 0.28614 kJ mol−1 K−1 and from 147.34 to 155.91 kJ mol−1, respectively, for the temperature range of 40–70 °C. Drying air temperature promoted darkening or tendency to loss of green color; increase in drying air temperature leads to greater discoloration, as well as a higher concentration of total phenolic compounds (about 221.10 mg GAE mL−1 g–1 dm), with a peak at temperature of 60 °C.

ABSTRACT: The drying agroindustrial products is used to preserve the sensory and nutritional quality and to reduce the biological activity, preventing deterioration and loss of commercial value. The objective was to study the mathematical modeling Guava bark drying to obtain flour and to determine and evaluate the effective diffusion coefficient, get the activation energy and the thermodynamic properties in drying temperatures of 45, 55, 65 and 75 °C. The experiment was conducted Instituto Federal Goiano - Campus Rio Verde, the guava was purchased in local shops in the city of Rio Verde Goiás, in the commercial maturity. Among the analyzed models, Midilli was the best to represent the drying phenomenon. The effective diffusion coefficient increased with increasing temperature and the activation energy for liquid diffusion drying was 37,207kJ mol-1. The enthalpy and entropy increased with increasing drying temperature. While the Gibbs free energy increased with increasing drying temperature.

ABSTRACT This study aimed to obtain the sorption isotherms of grain sorghum flour, fit mathematical models to experimental data, and recommend safe water levels for preserving the material at different temperatures. Sorghum grains with an initial moisture content of 34% dry basis (db) were subjected to drying at a temperature of 60 °C, reaching moisture contents ranging from 32.20 to 9.8% db. Water activity was obtained using Hygropalm Aw1 equipment placed inside a BOD chamber at temperatures of 10, 20, 30, and 40 °C. The experimental data were fitted to mathematical models frequently used to predict the isotherms of plant products. The modified Oswin model presented the best fit to estimate the sorption isotherms of sorghum flour. Safe moisture content limits for storing sorghum flour are 18.45, 17.3, 16.08, and 15.2% db for temperatures of 10, 20, 30, and 40 °C, respectively. The isosteric heat for the range of equilibrium moisture contents from 9.80 to 32.20% db varied from 2779.49 to 2498.46 kJ kg−1.

ABSTRACT Sorghum ( Sorghum bicolor L. Moench) is a crop of paramount importance for Brazil, used in human and animal food. Considering the reduced number of studies on the influence of using a densimetric table in seed processing and its respective reprocessing to the equipment, this study aimed to evaluate the physiological quality of processed sorghum seeds reprocessed in a densimetric table and stored for three months. The treatments consisted of four collection points in the terminal part of the densimetric table, representing the processing material: upper part (P1), upper middle part (P2), middle part (P3), and lower part (D). Subsequently, the samples that were reprocessed in the table came from P3 and were divided into the upper part, which was followed to bagging (P3R1), and the lower part (P3R2), which followed for disposal, totaling six treatments. Storage was performed in a refrigerated environment, using a completely randomized design, with the means being compared by Tukey’s test at 5%. We concluded that the reprocessing of sorghum seeds in the densimetric table can improve the physical quality of a lot due to its standardization at the end of the stages, contributing to the improvement of the physiological quality and use of the material that would be discarded. The equipment performance allows the removal of seed fractions with lower apparent specific mass and promotes positive stratifications in the physiological quality of sorghum seed lots.

O girassol (Helianthus annus L.) é uma das oleaginosas de maior importância na produção de óleo vegetal comestível, sendo seu uso comercial abrangente. Assim, o objetivo do presente trabalho foi avaliar o efeito de nove meses de armazenamento, em diferentes embalagens, na qualidade do óleo extraído dos grãos de girassol. Os grãos foram armazenados em ambiente natural, em diferentes embalagens (plástico de propileno, embalagem de polietileno de alta densidade (PEAD), garrafa PET e papel multifoliado) em três amostras. Posteriormente, foi realizada a extração do óleo dos grãos de girassol e a rotaevaporação do reagente nas amostras e, dessa forma, a obtenção do óleo bruto. As análises realizadas para avaliação e determinação da qualidade foram: teor de óleo, índice de acidez, índice de peróxido e índice de iodo. De acordo com os resultados obtidos, verificou-se que as embalagens e o tempo de armazenamento não influenciaram no teor de óleo dos grãos de girassol. A embalagem PET proporcionou maior incremento no índice de acidez e para o índice de peróxido as embalagens PEAD e PET proporcionaram os maiores valores ao final do armazenamento.

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ABSTRACT Bugs are pest insects that, when not adequately controlled, may cause significant losses in the soybean crop. Their damage to grains compromises delivery in the storage unit and storage success. Thus, the objective of this study was to evaluate, during storage, the effect of temperature and moisture content on soybean grain quality with high damage caused by bugs in the crop. The experiment was set in a completely randomized design with a 2 x 4 x 5 factorial design, with two moisture contents (11.75 and 13.84% (w.b.)), four storage temperatures (20, 25, 30 and 35 °C), and five evaluation periods (0, 2, 4, 6 and 8 months). The percentage of damaged/fermented, damaged, fermented, broken grains, and electrical conductivity were analyzed. It can be inferred that bug-damaged soybean grains have reduced quality when stored at higher temperatures and for more extended periods. It is not recommended to store bug-damaged grains in moisture contents of 13.84% (w.b.) at temperatures above 30 °C for longer than four months. Grains stored at 35 °C when not damaged by bugs, ferment after six months of storage. Bug-damaged grains evolve to fermented grains during storage.

Objetivou-se, neste trabalho, avaliar, ao longo do armazenamento, o efeito da temperatura e do teor de água em grãos de soja com elevada danificação por percevejo na lavoura, por meio da qualidade sanitária. Foram utilizados dois teores de água (11,75 e 13,84%, base úmida) e os grãos foram acondicionados em embalagens de polietileno de alta densidade (PEAD), armazenados em quatro câmaras climáticas (BOD), reguladas nas temperaturas de 20, 25, 30 e 35°C e avaliados a cada dois meses, analisando-se a atividade de água, sanidade dos grãos e índice de ocorrência. O experimento foi montado em delineamento inteiramente casualizado e em esquema fatorial 2 x 4 x 4, sendo dois teores de água, quatro temperaturas de armazenamento e quatro tempos de avaliação. O teor de água e as temperaturas ao longo do armazenamento influenciam a qualidade sanitária dos grãos de soja avariados por percevejo na lavoura. Quanto maior o teor de água e também a temperatura de armazenamento, mais elevada é a atividade de água dos grãos de soja danificados por percevejo bem como o incremento na ocorrência de fungos.

O tungue é uma espécie que apresenta potencial para a produção de biodiesel. Para um armazenamento seguro, há necessidade de conhecer sua higroscopicidade. Objetivou-se com este trabalho determinar as isotermas de dessorção, a partir da recomendação de um modelo matemático, definir os teores de água seguro para armazenamento e obter o calor isostérico, para as sementes de tungue. Para obtenção do teor de água de equilíbrio higroscópico, foi utilizado o método estático, utilizando-se 20 g de sementes, envolvidas por um tecido permeável e colocadas no interior dos dessecadores, contendo soluções de sais, em câmara tipo BOD com temperaturas de 20ºC, 25ºC, 30ºC e 35ºC; a atividade de água variou entre 0,14 e 0,812 decimal. Para ajuste dos modelos matemáticos, utilizaram-se os critérios de informação de Akaike (AIC), e, para auxiliar na escolha do melhor modelo, critérios de informação bayesiano de Schwarz (BIC). Dentre os modelos testados, foi selecionado o de Chung-Pfost, para representar as isotermas de dessorção das sementes de tungue. Os valores de calor isostérico integral de dessorção na faixa do teor de água de equilíbrio de 2,08 a 8,35 (% b.s.) variaram de 3754 kJ kg-1 a 2555 kJ kg-1.

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.

Sampling and homogenization of grains, which involves the actions of sample withdrawal, dilution and the preparation of the working sample, are essential in the representativeness and classification of the commercialized batch. Storage units should use sampling methods that provide safe collection and classification of the product, generating the necessary discounts and optimizing unit operations of grain preprocessing. The grain homogenizers must be efficient in the uniformization and division of the sample, besides being fast and low noise level during the operation. Thus, the objective of this study was to detail the procedures and equipment used for sampling, homogenization and dilution (reduction) of work samples, in the determination of the quality of grains upon receipt and dispatch in storage units. The equipment for grain sampling (pneumatic probe, manual composite calender 1.8 m brass with three stages, 2.1 m manual composite caliper with three stages, manual composite caliper 2.10 m of one stage and sampler pelican type. Also described the grain homogenizers Boerner, 16:1 multi-channel reducer and 4:1 multi-channel reducer. Therefore, the storage units must use sampling methods that offer security in the collection and classification of the product, generating the necessary discounts and optimizing the unit operations of the pre-processing of the grains. The grain homogenizing equipment must be efficient in standardizing and dividing the sample, in addition to presenting speed and low level of noise during operation.

ABSTRACT Tamarind is used in the food and pharmaceutical industry, and its seed is the main means for the reproduction of this species, thus justifying studies that ensure its post-harvest viability. This research aimed to study the thermodynamic properties of tamarind seeds as a function of the equilibrium moisture content. The experimental data of the water activities were obtained by the indirect static method. The Cavalcanti Mata model was used to determine the thermodynamic properties of tamarind seeds, as it was the model that best fitted the experimental data of the desorption isotherms. The results showed that the thermodynamic properties are influenced by the moisture content and temperature, with an increase in the energy required to remove water from the product with a decrease in moisture content. The net isosteric heat of desorption increases with a reduction of moisture content ranging from 2,618.85 to 2,510.25 kJ kg−1 for the moisture content range of 10.52 to 21.10% db. The latent heat of vaporization, the differential enthalpy, and the Gibbs free energy increase with a reduction of the moisture content of tamarind seeds.

ABSTRACT The knowledge of hygroscopicity is essential for the storage of tamarind seeds, but there is a limitation of a judicious statistical parameter to define the best mathematical model to adjust the isotherms of plant products. Therefore, this study aimed to determine the desorption isotherms of tamarind seeds and test the Akaike information criterion (AIC) and Schwarz Bayesian information criterion (BIC) for choosing the best mathematical model. Seeds with an initial moisture content of 21.00 ± 0.10% dry basis (db) were dried at 45 °C until they reached moisture contents of 17.27 ± 0.10, 15.04 ± 0.16, 14.14 ± 0.06, 12.41 ± 0.17, and 10.52 ± 0.12% db. The water activity of the product was determined by the static-indirect method at temperatures of 10, 20, 30, and 40 °C. Mathematical models frequently used to predict the isotherms of plant products were adjusted to the experimental data. The Cavalcanti Mata model is recommended to estimate the desorption isotherms of tamarind seeds because it presents better adjustments. The AIC and BIC criteria contribute to the choice of the model to predict the desorption isotherms of tamarind seeds.

Condiments and culinary supplements are subjected to long-term storage and may undergo physical, chemical, and biological changes that can influence their quality. Thus, the objective of the present study was to analyze the drying kinetics of rose pepper (Schinus terebinthifolius Raddi) fruits in an oven with forced air circulation at different temperatures, namely, 45, 55, 65, and 75°C, and determine the effective diffusion coefficient and activation energy using different mathematical models. Furthermore, the effects of the different drying temperatures were analyzed for external color parameters and yield of essential oil contents by gas chromatography coupled to a mass spectrometer. Of the ten models used for fitting, Thompson’s model was one with the best fitting to represent the drying of rose pepper fruits. The diffusion coefficient increases with the elevation of drying air temperature, described by the Arrhenius equation, with activation energy of 53.579 kJ·mol−1. The color of the fruits decreased in lightness (L∗) with the increase in temperature. Of the thirty-eight terpenes identified, α-pinene and cis-ocimene were the most abundant, with the overall highest yield being found at a drying temperature of 45°C.

ABSTRACT Drying is the most widely used process to ensure the quality and stability of plant products. Therefore, this study aimed to determine the effective water diffusivity and activation energy in grain sorghum during drying at different temperatures and initial moisture contents. Sorghum grains (cultivar DeKalb 640) were harvested with an initial moisture content of 0.49 kg water kg−1 dry matter. The effective diffusion coefficient was determined from different initial moisture contents of approximately 0.49, 0.40, 0.31, and 0.23 kg water kg−1 dry matter. Grains with different moisture contents were dried under four temperature conditions of 40, 60, 80, and 100 °C on perforated trays. The spherical geometry model was used for liquid diffusion. The experiment was conducted in a completely randomized design in a 4 × 4 factorial scheme (four moisture contents × four temperatures), with three replications. Data were subjected to analysis of variance and regression using the statistical software SISVAR®. Sorghum grain diffusivity increases at the same drying temperature as an increase of the initial moisture content of grains. The activation energy was higher for grains with higher initial moisture content, with values of 27.32, 26.75, 22.55, and 20.94 kJ mol−1, respectively.

Background: Inefficient use of public funds can have a negative impact on the lives of citizens. The development of machine learning-based technologies for data visualisation and prediction has opened the possibility of evaluating the accountability of publicly funded projects. Methods: This study describes the conception and evaluation of the architecture of a system that can be utilised for project profile definition and prediction. The system was used to analyse data from 20,942 System of Management of Agreements and Transfer Contracts (SICONV) projects in Brazil, which are government-funded projects. SICONV is a Brazilian Government initiative that records the entire life cycle of agreements, transfer contracts, and partnership terms, from proposal formalisation to final accountability. The projects were represented by seven variables, all of which were related to the timeline and budget of the project. Data statistics and clustering in a lower-dimensional space calculated using t-SNE were used to generate project profiles. Performance measures were used to test and compare several project-profile prediction models based on classifiers. Results: Data clustering was achieved, and ten project profiles were defined as a result. Among 25 prediction models, k-Nearest-Neighbor (kknn) was the one that yielded the highest accuracy (0.991±0.002). Conclusions: The system predicted SICONV project profiles accurately. This system can help auditors and citizens evaluate new and ongoing project profiles, identifying inappropriate public funding.

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.