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Postharvest conservation methods such as heat shock can increase the nutritional profile of fruits, inducing greater accumulation of antioxidants that participate in the physiological maintenance of fruits. The objective of this work was to evaluate the antioxidant properties of “Sweet Grape” tomatoes treated with heat shock in pre-storage. “Sweet Grape” tomatoes were heat shocked in hot water (45°C) for 10 min. and stored at room temperature for 9 days. β-carotene, ascorbic acid, total phenolic compounds, and antioxidant activity (DPPH, ABTS, and FRAP) were evaluated every 3 days. The pulp and skin of the treated tomatoes had higher β-carotene content than the control during storage, according to the findings. The content of total phenolic compounds in the pulp reduced, regardless of the treatment. There was a reduction of ascorbic acid, but with significantly higher values ​​in the fruits treated on the third and sixth days of storage. The DPPH antioxidant activity of the pulp decreased, regardless of the treatment. In the skin there was a significant effect of the treatment until the sixth day. There was no variation in the ABTS antioxidant activity of the pulp of the treated tomatoes. There was no significant effect of heat shock on the FRAP antioxidant activity of the pulp until the sixth day. Heat shock promoted an increase in β-carotene in tomato skin, which was related to increases in its DPPH antioxidant activity. The heat shock treatment promoted greater retention of ascorbic acid in the fruit, but it was not able to avoid its reduction during storage. The tomatoes’ antioxidant biochemical response to heat shock is most expressed in their skin.

Silver nanoparticles (AgNPs) can be produced through an easy and safe process called green synthesis and have been considered an efficient antimicrobial agent. The antimicrobial effect of silver nanoparticles green synthesized with E. tirucalli (aveloz) can be a promising technique for preserving stored strawberries. The objective of this work was to perform a green synthesis of AgNPs with aveloz extract (Av) and evaluate its effect on the physiology and preservation of stored strawberries. Silver nitrate was reduced with Av to produce Av-AgNPs. The Av-AgNPs were characterized by Scanning Electron Microscope, Energy Dispersive X-ray Spectrometry, and laser diffraction. The in vitro antifungal activity of Av-AgNPs was evaluated against Botrytis cinerea and Rhizopus stolonifer. Strawberries were treated with Av-AgNPs and stored (5 °C) for 12 days. Respiratory rate, decay, fresh mass loss, firmness, total phenolics and antioxidant activity of the strawberries were evaluated. According to the results, Av-AgNPs synthesis was performed, and it presented sizes between 40 and 90 nm. Av-AgNPs inhibited B. cinerea but was less effective for R. stolonifer. Total phenolic compounds, antioxidant activity, fresh mass loss and firmness of strawberries were not influenced by Av-AgNPs. Treated strawberries had a lower respiratory rate than the control and showed no symptoms of microbiological deterioration until 9 days of storage, while in the control the deterioration symptoms started after 3 days. This study showed that the green synthesis of AgNPs with Av produced nanoparticles smaller than 100 nm, and that they were effective against strawberries decay during storage, indicating to be a promising protection technique against decay.

Bioactivity of “espinheira-santa” leaves can be evaluated through solvent purification processes. Species of the same genus may contain different compounds, which may be separated by conventional chromatography using different solvents. The extraction process also influences the contents of these compounds. In order to optimize the above process research is required on variables such as solvents, temperature and extraction time. The objective of this work was to evaluate the antioxidant activity (ABTS, DPPH and FRAP) of extracts and purified fractions from leaves of Maytenus ilicifolia and M. aquafolium. Percolation at 28 °C for 7 days, and ultrasound at 50, 60 and 70 °C for 15 min were the extraction methods tested. Open column chromatography (silica gel) was used in the fractionation of extracts, and hexane, chloroform and methanol were the elution solvents used. The evaluation methods of the antioxidant activity were DPPH, FRAP and ABTS. Plant species showed no significant differences between methods for DPPH, but the fractions obtained with chromatography had significant differences, the crude ethanolic extract (CEE) and the methanolic been in general superior. “espinheira-santa” is a plant with antioxidant potential, but the extraction methods are not optimal. Still, it can be said that the separation by chromatography provided a better visualization of the nature of the components of that plant that best stood out in relation to the antioxidant activity.

Silver nanoparticles (AgNPs) can be produced through an easy and safe process called green synthesis and have been considered an efficient antimicrobial agent. The antimicrobial effect of silver nanoparticles green synthesized with E. tirucalli (aveloz) can be a promising technique for preserving stored strawberries. The objective of this work was to perform a green synthesis of AgNPs with aveloz extract (Av) and evaluate its effect on the physiology and preservation of stored strawberries. Silver nitrate was reduced with Av to produce Av-AgNPs. The Av-AgNPs were characterized by Scanning Electron Microscope, Energy Dispersive X-ray Spectrometry, and laser diffraction. The in vitro antifungal activity of Av-AgNPs was evaluated against Botrytis cinerea and Rhizopus stolonifer. Strawberries were treated with Av-AgNPs and stored (5 °C) for 12 days. Respiratory rate, decay, fresh mass loss, firmness, total phenolics and antioxidant activity of the strawberries were evaluated. According to the results, Av-AgNPs synthesis was performed, and it presented sizes between 40 and 90 nm. Av-AgNPs inhibited B. cinerea but was less effective for R. stolonifer. Total phenolic compounds, antioxidant activity, fresh mass loss and firmness of strawberries were not influenced by Av-AgNPs. Treated strawberries had a lower respiratory rate than the control and showed no symptoms of microbiological deterioration until 9 days of storage, while in the control the deterioration symptoms started after 3 days. This study showed that the green synthesis of AgNPs with Av produced nanoparticles smaller than 100 nm, and that they were effective against strawberries decay during storage, indicating to be a promising protection technique against decay.

The aim of this study was to evaluate the physiological response and quality of the ‘Tahiti’ acid lime coated with carboxymethylcellulose (N-CMC), pectin (N-PEC) and starch (N-ST) nanocomposites based on cellulose nanocrystals (NC). Respiratory rate, ethylene production, loss of fresh weight, total chlorophyll and fruit firmness were evaluated during 9 days of storage. At the end of storage, only fruits coated with N-CMC and N-PEC exhibited significantly lower ethylene yield (0.92 and 0.98 μg C2H4 kg-1 h-1, respectively) than fruits coated with CMC and PEC (1.6 and 2.02 μg C2H4 kg-1 h-1, respectively). On the 3rd day of storage, fruits coated with N-PEC showed a respiratory rate (12.01 mg CO2 kg-1 h-1) similar to the fruits of the control (13.52 mg CO2 kg-1 h-1), but it was significantly lower than the fruits coated with PEC (14.93 mg CO2 kg-1 h-1). Only fruits coated with N-PEC showed significantly lower fresh weight losses than the control fruits. Fruits coated with N-PEC had chlorophyll retention levels (18.95 mg g-1) higher than fruits with PEC (13.25 mg g-1). This work showed that the N-PEC nanocomposite, based on NC, was the coating that showed greater potential for preserving quality of the ‘Tahiti’ acid lime.

Ethanol can inhibit ethylene and retard decay of several fruit. However, the effect of ethanol on ethylene and oxidative stress has not yet been observed in bananas. In this work, the effect of ethanol (vapor phase) on physiology and conservation of the banana cv. 'Prata' was investigated. Initially, a group of bananas was analyzed during 8 h of exposure to ethanol, and then another group of bananas was exposed to ethanol for 4 h and then analyzed during 12 days of storage. Ethanol and ethylene concentrations, respiration rate, superoxide dismutase and catalase activities, physico-chemical characteristics and fruit decay were evaluated. Ethanol reduced ethylene production and respiration rate of the banana only when it reached 4 h of exposure, and this was associated with a maximum absorption of ethanol in the fruit peel. Ethanol increased superoxide dismutase and catalase activities from fruit peel only in the first 2 h of exposure to ethanol, i.e. ethanol did not generate significant oxidative stress. During storage, ethanol inhibited ethylene production and was also able to delay fruit decay, but it was not able to influence the respiration rate, conversion of sugars, and fresh weight loss of the fruits. This study showed that ethanol vapor has an inhibitory effect on ethylene metabolism, but it has no potential to control post-harvest ripening of the banana cv. 'Prata'. On the other hand, ethanol delays decay, and this extends fruit shelf life, which is commercially advantageous.

The search for alternatives to exploit nutritional and functional properties of agro-industrial by-products has stimulated the development of researches. Agro-industries have targeted different native fruits, such as jabuticaba, to produce juices or candies. Jabuticaba have high nutritional value, and its industrial residues can also contain nutritional compounds that may be recovered. The objective of this work was to verify storage effects on anthocyanin and flavonoid contents, color and physical-chemical features from agro-industrial by-products of two genotypes of jabuticaba (Clevelândia and Vere) and two industrial processes of juice extraction (crushing and steam). By-product samples were ground and the powder was packaged on vacuum, and was then stored during 135 days. The powdered peel of both Jabuticaba genotypes are rich in flavonoids and steam extraction was more effective to obtain the peel. Clevelândia genotype had higher anthocyanin content, but both genotypes showed high levels of this compound. Color quality is enhanced when dehydrated with attractive pigmentation for blends in food. Thus, jabuticaba peel has significant nutritional and functional levels, being a good source of fiber, ash, natural pigment and phenolic compounds. It can be used in food products such as bioactive ingredient. Key words: Myrciaria cauliflora, shelf life, by-products.

Heat shock and salicylic acid have been studied on shelf-life extension of fruits. The benefits of these techniques have been related to their effect on inducing physiological defense responses against the oxidative stress and pathogen development. The objective of this study was to evaluate the effect of heat shock and salicylic acid on the postharvest preservation and contents of total phenolics, anthocyanins, ascorbic acid, fresh weight loss and microbiological quality of organic strawberries cv. Dover. Strawberries produced organically and stored at 5 ºC were subjected to heat shock (45 ºC ± 3 ºC for 3 h), application of salicylic acid (soaking in 2.0 mmol L^-1 solution), heat shock in combination with salicylic acid and control. After treatment, the fruits were packed and stored in a climatic chamber at 5 ºC ± 2 ºC. At 1, 7 and 14 days, the experimental units were removed from refrigeration and kept at room temperature of approximately 20 ºC for two days. There was no effect of treatments on fresh weight loss, incidence of pathogens or chemical variations in strawberry fruits during the storage period. In natural conditions, organically grown strawberries remained in good condition for sale up to seven days of storage in all treatments. O choque térmico e o uso do ácido salicílico têm sido estudados como técnicas de extensão da vida útil de frutos. A ação benéfica dessas técnicas tem sido relacionada com seus efeitos na indução de respostas fisiológicas de defesa contra estresses oxidativos e desenvolvimento de patógenos. O objetivo deste trabalho foi avaliar o efeito do choque térmico e do ácido salicílico na conservação pós-colheita e nos teores de compostos fenólicos totais, antocianinas, ácido ascórbico, perda de matéria fresca e qualidade microbiológica de frutos de morangos 'Dover', produzidos organicamente e armazenados a 5 ºC. Os morangos foram submetidos aos tratamentos de choque térmico (45 ºC ± 3 ºC, por 3 h), aplicação de ácido salicílico (imersão em solução aquosa 2,0 mmol L^-1), combinação de choque térmico com ácido salicílico e controle. Após tratamento, os frutos foram embalados e armazenados em câmara climatizada, a 5 ºC ± 2 ºC. Em intervalos de 1, 7 e 14 dias, as unidades experimentais foram retiradas da refrigeração e mantidas em ambiente a aproximadamente 20 ºC, por dois dias. Não houve influência dos tratamentos sobre a perda de matéria fresca e a incidência de patógenos ou variações químicas em frutos de morango, durante o período de armazenamento. Natural-mente, os morangos produzidos organicamente mantiveram-se em boas condições para a comercialização até sete dias de armazenamento, em todos os tratamentos.

O objetivo deste trabalho foi avaliar as características químicas e a conservação do maracujá-amarelo embalado com filme de PVC durante o armazenamento refrigerado a 5 ºC. Atividade antioxidante (DPPH e TEAC), compostos fenólicos totais, β-caroteno e ácido ascórbico do suco do fruto foram os parâmetros químicos avaliados. As estimativas de perda de massa, enrugamento, cor e sintomas de patógenos foram utilizadas no estudo de conservação. As avaliações foram realizadas em intervalos de 10 dias, durante 40 dias. De acordo com os resultados, o teor de fenólicos totais aumentou durante o armazenamento, com variações entre 20,10 e 21,29 mg EAG 100 mL-1. O conteúdo de ácido ascórbico aumentou até o 20º dia de armazenamento (33,58 mg 100 mL-1), mas seguiu com decréscimos até o 40º dia (21,67 mg 100 mL-1). Independentemente do uso de PVC, o conteúdo de β-caroteno não variou durante o armazenamento. As atividades antioxidantes DPPH e TEAC do suco diminuíram durante o armazenamento. Não foram encontradas correlações positivas entre as atividades DPPH e TEAC e o teor de fenólicos totais, sugerindo que este último não contribui para a atividade antioxidante do suco do maracujá. O uso da embalagem de PVC não influenciou positivamente a atividade antioxidante e os teores de fenólicos totais e ácido ascórbico do suco do maracujá-amarelo durante seu armazenamento. A embalagem de PVC não inibiu sintomas de desenvolvimento de patógenos por até 30 dias de armazenamento, a 5 ºC, mas reduziu a perda de massa fresca e o enrugamento do fruto, proporcionando condições ótimas de comercialização por até 20 dias. The aim of this study was to evaluate the chemical characteristics and conservation of yellow passion fruit packed with PVC film during refrigerated at 5 ºC. Antioxidant activity (DPPH and TEAC), total phenolic compounds, β-carotene and ascorbic acid of the fruit juice were the chemical parameters. Estimations of weight loss, wrinkling, color and symptoms of pathogens were used in the conservation study. The evaluations were performed in 10-day intervals for 40 days. According to the results, the total phenolic content increased during storage, varying between 20.10 and 21.29 mg EAG 100 mL-1. The contents of ascorbic acid increased until the 20th day of storage (33.58 mg 100 mL-1), but followed with decreases until the 40th day (21.67 mg 100 mL-1). Regardless of the use of PVC, β-carotene did not change during storage. The TEAC and DPPH antioxidant activity in juice decreased during storage. The DPPH and TEAC antioxidant activity did not correlate positively with total phenolics, suggesting that phenolic compounds do not contribute to the antioxidant activity of passion fruit juice. The use of PVC packaging did not influence positively on the antioxidant activity and the contents of total phenolics and ascorbic acid of yellow passion fruit juice during storage. The PVC did not inhibit the pathogens-degradation symptoms for up to 30 days of storage, at 5 ºC, but reduced the weight loss and wrinkling of the fruit, providing optimal conditions of merchantability for up to 20 days.

Neste trabalho, os conteudos de compostos fenolicos totais, B-caroteno, acido ascorbico e a atividade antioxidante (pelos metodos DPPH e TEAC) foram determinados no suco do maracuja-amarelo durante o armazenamento a 5 e 24 oC, em intervalos de 10 dias, durante 40 dias. A qualidade dos frutos foi determinada durante o armazenamento, tomando como parâmetros as variaveis perda de massa, enrugamento, cor da casca e o indice de degradacao por patogenos. Amostras de frutos em estadio de maturacao com a cor da casca predominantemente verde, em inicio de amarelecimento, foram utilizadas nos ensaios. Os teores de compostos fenolicos totais e B-caroteno, e a atividade antioxidante do suco do maracuja-amarelo nao foram influenciados pela temperatura de armazenamento. O conteudo de compostos fenolicos totais do suco aumentou com o tempo de armazenamento. Os efeitos da temperatura de armazenamento foram mais evidentes e impactantes na aparencia do fruto do que na qualidade nutricional do suco. A atividade antioxidante do suco, expressada em sequestro do radical DPPH, diminuiu durante o armazenamento. Com base na qualidade microbiologica, a vida util do maracujaamarelo se estendeu ate 20 dias no armazenamento refrigerado.

que representa leite de alta qualidade. Um total de 12.221 registros de CBT do leite foi obtido de uma industria lactea da regiao Oeste do Parana, no periodo de janeiro a outubro de 2006. Apos as coletas, a qualidade do leite foi analisada em laboratorio pelo metodo de citometria de fluxo. Os dados de CBT foram classificados por sistema de ordenha, tipo de resfriador e intervalos da CBT, segundo criterio da Instrucao Normativa 62, e submetidos a analise de independencia de Qui-Quadrado. As propor -coes de CBT do leite entre tipos de resfriadores, em cada sistema de ordenha, foram comparadas utilizando-se a estatistica calculada Z. Observou-se menor (p < 0,01) valor de CBT do leite de vacas submetidas a ordenha canalizada e do leite resfriado a granel. A proporcao das amostras de leite avaliadas nos tres niveis de CBT resfriadas por sistema de imersao nao diferiu (p = 0,1549) do leite resfriado a granel, quando o leite foi obtido de rebanhos ordenhados por ordenha canalizada. A alta qualidade microbiologica do leite da regiao Oeste do Parana e obtida quando os produtores utilizam em suas propriedades rurais a ordenha canalizada e o sistema de resfriamento a granel.PALAVRAS-CHAVE: Higienizacao, ordenhadeira, qualidade microbiologica, resfriador.ABSTRACTTOTAL BACTERIAL COUNT OF MILK IN DIFFERENT SYSTEMS OF MILKING AND COOLING. This study aimed to evaluate the effect of milking systems and cooling on total bacterial count (TBC), and the amount of milk samples with TBC ≤ 10

Este trabalho teve como objetivo avaliar o conteúdo de antocianinas, fenóis totais, taninos e ácido ascórbico, em variedade de uva 'Bordô', cultivada sobre os porta-enxertos '420A', 'IAC-766' e 'Ripária-do-Traviú', em três períodos de colheita distintos. O experimento foi realizado em vinhedo de uva 'Bordô', no município de Missal, no Oeste do Paraná, na safra 2007/2008. O efeito dos porta-enxertos foi avaliado em três períodos de colheita, a partir da época de floração: 90 dias, com bagas em amadurecimento, tendendo ao roxo definitivo; 100 dias, com bagas totalmente roxas; e 110 dias, com bagas em sobrematuração. Foi utilizado o delineamento em blocos casualizados, em parcelas subdivididas no tempo. As variáveis analisadas foram sólidos solúveis, acidez titulável, índice de fenóis totais, antocianinas, taninos e teor de ácido ascórbico. Os resultados mostraram que, nos porta-enxertos '420A' e 'IAC-766', a uva 'Bordô' apresentou respostas similares em acúmulos de antocianinas, taninos, acidez titulável e sólidos solúveis, mas os acúmulos de fenóis totais, tanto na polpa, quanto na epiderme das bagas, foram maiores no '420A'. Ocorreram menores acúmulos de antocianinas, fenóis totais e taninos da epiderme da uva 'Bordô', quando enxertada em 'Ripária-do-Traviú'. Acúmulos superiores de ácido ascórbico foram verificados nas uvas enxertadas em 'IAC-766'. Há evidências que apontam o porta-enxerto 'Ripária-do-Traviú' como inferior aos demais, nos aspectos nutricional e enológico. This study aimed to evaluate the content of anthocyanins, total phenols, tannins and ascorbic acid in grape grown onto '420A', 'IAC-766' and 'Ripária-of-Traviú' rootstocks in three different harvest periods. The experiment was conducted in 'Bordo' grapes vineyard in Missal city, Paraná West, in the 2007/2008 harvest. The rootstock effect was evaluated in three periods after flowering: 90 days, with ripening berries , tending to a definite purple; 100 days, with berries completely purple , and 110 days, with berries overripening. The experiment was arranged in a split plot design in randomized blocks. The variables soluble solids, titratable acidity, total phenols index, anthocyanins, tannins and ascorbic acid were analyzed. The results showed that in the rootstocks '420A' and 'IAC-766', the 'Bordô' grape showed similar responses for anthocyanins, tannins, acidity and soluble solids accumulation, but the contents of phenolic compounds in the pulp and epidermis of berries were higher in '420A'. On the rootstock 'Ripária-do-Traviú', the 'Bordô' grape showed lower accumulation of anthocyanins, total phenols and tannins in the epidermis. Higher accumulations of ascorbic acid were found in 'Bordô' grapes on the rootstock 'IAC-766'. There is evidence suggesting that the 'Ripária-do-Traviú' rootstock as inferior to others in nutritional and enological aspects.

This study evaluated the effect of drying temperature on the total phenolic compounds, lycopene and ascorbic acid contents, color and sensory quality of dried tomato. Tomatoes cv. Dominador were dried at 55, 65, 75 and 85 °C. The instrumental color of dried tomato was determined separately on the sides of pulp and peel. In affective sensory analysis appearance, color, aroma, flavor and texture attributes were considered. Acceptance index and purchase intent were also evaluated. According to the results, increasing concentrations of phenolic compounds and lycopene were observed with increased drying temperature to 75 °C. Significant decrease in ascorbic acid content was observed during drying, which ranged from 38.82 ± 2.47 mg 100 g-1 after drying at 55 °C, dropping to 21.68 ± 1.30 mg 100 g-1 at 85 °C. Significant decrease in values of a* and L* were observed on both sides of the dried tomato slices (pulp and peel), showing that the increase in temperature causes loss of red color and browning of dried tomato. According to sensory analysis, among the temperatures tested in drying tomatoes the one that showed best results was 75 °C. This study showed that drying-conventional tomato with air heated to 75 °C is the most recommended among the temperatures tested.

Objetivou-se avaliar os efeitos da adição da monensina sódica na dieta de ovinos sobre o consumoe os coeficientes de digestibilidade aparente da fibra em detergente neutro (FDN) e ácido (FDA) num ensaio dedigestibilidade “in vivo”, utilizando-se 16 ovelhas, não prenhes e não lactantes, mestiças, com peso e desviopadrão médios de 55,11 ± 3,11 kg, em delineamento inteiramente ao acaso, com quatro tratamentos (0; 25; 50 e75 mg de monensina/animal/dia). Os animais foram alimentados à vontade, com dietas à base de cana-deaçúcar,farelo de soja, grão de milho moído e mistura mineral como dieta básica. Houve efeito significativo dosníveis de monensina sobre os consumos das fibras em detergentes neutro e ácido da dieta. Os coeficientes dedigestibilidade aparente da FDN e da FDA não diferiram estatisticamente entre os tratamentos. Os níveis demonensina sódica utilizados diminuíram os consumos e os coeficientes de digestibilidade aparente daFDNe daFDA.

The objective of this work was to evaluate the effect of the productive profile of the producers and the seasonal period on the counting of somatic cells in formal milk from Marechal Cândido Rondon city producers, in Parana State. The productive profiles had been established with the data of the milk daily production of 1580 producers registered in cadastre of FRIMESA dairy industry in 2004, as the following intervals: less than 50; 50 and 100; 100 and 250; 250 and 400; and bigger than 400 L.day-1. For the study of the influence of the productive profile, the following intervals of CCS had been used: less than 0,4x106; 0,4x106 and 0,75x106; 0,75x106 and 1,0x106; and bigger of 1,0x106 SC.ml-1. In regard to the study on the influence of the seasonal period, the values of CCS had been transformed in somatic cells scores for accomplishment of the statistical analyses. From the showed producers, 7.9% had not taken care of to the current regulation for the CCS, therefore they had presented flocks with milk above of 1,0x106 CS.ml-1. The increase of the productive profile, in liters of milk legalized per day, implied in the increase of the percentage of flocks with milk presenting counting above of 1,0x106 CS.ml-1. For the climatic conditions of the city, milk displayed greater counting of somatic cells in the summer. The majority of producers (65%) presented productive profile less than 100 liters of legalized milk for day.

Objetivou-se avaliar os efeitos da adição da monensina sódica no consumo de alimentos e no pH do líquido ruminal em ovinos. Foram utilizadas quatro ovelhas da raça Santa Inês, não prenhas, não lactantes e canuladas no rúmen. O delineamento experimental utilizado foi o quadrado latino, com quatro tratamentos (T1 - 0; T2 - 25; T3 - 50 e T4 - 75 mg de monensina/ animal/dia). Foram avaliados o consumo de ração, de matéria seca e o pH do fluido do rúmen. A colheita do líquido ruminal para determinação do pH foi realizada às 0; 2; 4; 6 e 8 horas após a alimentação. As análises de variância para consumo de ração e de matéria seca mostraram não haver efeito significativo dos níveis de monensina. Não foi observado efeito significativo nos valores médios do pH ruminal de cada tratamento e na interação tratamento x tempo; os valores de pH ruminal foram considerados normais. Houve diferença estatística no decorrer das horas. O consumo voluntário de alimentos e o pH do líquido ruminal não foram influenciados pela adição da monensina sódica na dieta dos ovinos, para a qual os valores de pH permaneceram elevados, caracterizando um bom ambiente de fermentação ruminal.

Objetivou-se neste trabalho avaliar a qualidade físicoquímica de carne suína durante o descongelamento, mediante determinação das variações de massa e de nitrogênio por exsudação (gotejamento). Amostras de 300 g de carne de lombo suíno das raças Landrace, Large White e Piau foram congeladas e depois submetidas ao descongelamento lento. As avaliações das amostras das três raças ocorreram em três tempos de descongelamento (6, 12 e 24 horas). A carne da raça Piau evidenciou a menor perda de massa por gotejamento e a da raça Landrace revelou maior perda de massa até 12 horas de descongelamento. A raça não exerceu efeito sobre o teor de nitrogênio total contido nos exsudados dos lombos nos três períodos avaliados. No entanto, houve elevação significativa na concentração de nitrogênio do exsudado com o aumento do tempo de descongelamento para as três raças estudadas.

This study evaluated the effect of different plastic packings on dry A. blazei mushrooms, in terms of water activity, color and microbial growth during storage. Samples of 50 g dry mushrooms were wrapped in polypropylene (60 µm), low-density polyethylene (50 µm), double laminated biaxially oriented polypropylene (44 µm) and double laminated metallic biaxially oriented polypropylene (40 µm). Storage periods lasted 0, 45, 90, 135, 180, 225 and 270 days at 25°C and 80%RH. Microbiological analyses of mould and yeasts were carried out before and after storage period. The results showed that the polypropylene packing promoted the greatest increase of water activity and browning in the mushrooms, followed by the low-density polyethylene and the double biaxially oriented polypropylene packings. Storage in the double metallic biaxially oriented polypropylene packing retained the color. There was no increase, though, in the development of mould and yeasts in the mushrooms in any of the plastic packings studied

Orientador: Marlene Rita de Queiroz Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola Resumo: A finalidade principal deste trabalho foi reunir subsídios para orientar os processos desecagem, armazenagem e reidratarão do cogumelo Shiitake. A pesquisa foi realizada durante o ano de 2002 no Laboratório de Tecnologia Pós-Colheita/Secagem da Faculdade de Engenharia Agrícola da Universidade Estadual de Campinas e consistiu em duas etapas: secagem e armazenagem por 3 meses. Os fatores estudados foram: na secagem - geometria de corte (Shiitake inteiro e fatiado), temperatura de secagem (50ºC e 70°C), teor de umidade final (5% e 15%); na armazenagem - geometria de corte (Shiitake inteiro e fatiado), teor de umidade inicial (5% e 15%), embalagem (com e sem saco de polipropileno) e tempo de armazenagem (3 meses); na reidratação - tempo de imersão em água (8 tempos), geometria de corte (Shiitake inteiro e fatiado), teor de umidade inicial (5% e 15%) e tempo de armazenagem (3 meses). Os parâmetros de qualidade estudados foram: cor, textura, massa, teor de umidade, capacidade de reidratação. Os parâmetros de secagem estudados foram: cinéticas experimentais de secagem. As cinéticas de secagem mostraram que a secagem ocorreu no período de taxa decrescente e que a secagem dos cogumelos fatiados secos à 70ºC ocorreu em menor tempo que os demais tratamentos. A temperatura de secagem de 70ºC proporcionou menor escurecimento e os resultados do efeito da secagem sobre a textura do cogumelo foram pouco conclusivos. O tempo de armazenagem afetou a qualidade dos cogumelos ocorrendo maior dureza, gomosidade e escurecimento. Entretanto, o uso da embalagem retardou o escurecimento. Cogumelos fatiados armazenados com 15% de umidade inicial e embalados obtiveram pouca variação de mastigabilidade, teor de umidade e massa durante a armazenagem. O tempo de armazenagem provocou redução da capacidade de reidratação para os cogumelos com 5% de umidade inicial. Os cogumelos fatiados, com 5% de umidade inicial e embalados obtiveram valores de reidratação superiores aos demais tratamentos Abstract: Mushroom (Shiitake), drying, storage and re-hydration: effect on quality parameter process determinations. To orient drying, storage and re-hydration processes, accumulated subsidies by studying some parameters on mushroom Shiitake. During three months, drying, storage and re-hydration processes, were studied on mushroom in 2002 at Drying/Post-harvesting Technology Lab from Agricultural Engineering School of the Campinas State University. In drying process were studied: drying temperature (50º and 70 ºC), final moisture content (5% and 15%), cutting geometry (mushroom whole and sliced); in re-hydration process besides drying temperature and cutting geometry, were assessed also, water immersion (8 times), initial moisture content (5%% and 15%) and storage time (3 months); in packing up process; (with/without polypropylene bag), storage time (3 months) and initial moisture content were evaluated. Color, texture, mass, moisture content, and re-hydration capacity, were also evaluated. Drying kinetics showed that drying occurred at increased rate in the period and sliced mushroom dried at 70º C, occurred in lesser time than other treatments. Drying temperature at 70 ºC had less darkening and the results on mushroom texture drying effects were not conclusive. Drying time affected mushroom quality, occurring great hardness, gummosis and darkening. However, packing up use, delayed the darkening. Stored sliced and wrapped mushrooms with 15% initial moisture content had less, chew property variation, moisture content and mass during storage. Storage time provoked rehydration capacity decrease on mushrooms with 5% of initial moisture. Sliced and wrapped mushrooms, with 5% initial moisture, had re-hydration values greater than other treatments Mestrado Tecnologia Pós-Colheita Mestre em Engenharia Agrícola