Resumo Um grande desafio da cadeia produtiva da manga é a manutenção da qualidade pós-colheita desta fruta para exportação com o foco na segurança de alimentos. Este trabalho avaliou o efeito do tratamento hidrotérmico associado ao etanol sobre a qualidade da manga. Realizaram-se dois testes, e em ambos se utilizaram mangas ‘Tommy Atkins’. No primeiro, o tratamento térmico consistiu na imersão dos frutos em banho a 46,1°C/75 minutos, com concentrações de etanol 0, 5, 10 e 20% v/v, resfriamento em banho (21,1°C/30 minutos) e armazenados (25°C). No segundo, os frutos foram submetidos aos banhos, porém utilizaram-se concentrações de etanol a 0; 3; 5 e 7% v/v e armazenamento em 25°C e 10 ºC. Realizaram-se análises físico-químicas, fitopatológicas e porcentagem de podridão das mangas. Mangas tratadas com mais de 10% de etanol (armazenamento a 25°C), ou aquelas tratadas a concentrações de etanol inferiores a 7% (armazenados a 10ºC) não apresentaram boa aparência externa. Concluiu-se que o etanol, nas concentrações de 3; 5 e 7% v/v, associado à hidrotermia, não afetou os parâmetros de qualidade dos frutos armazenados a 25ºC, porém esses tratamentos diminuíram a vida de prateleira das mangas, uma vez que esses frutos amadureceram mais rápido, não sendo recomendados para tratamento das mangas para exportação.

Abstract One of the great challenges of the mango production chain is the maintenance of post-harvest quality of this fruit for export with a focus on food safety. This study evaluated the effect of the hydrothermal treatment associated to ethanol on mango’s quality. Two tests were performed, in both were used ‘Tommy Atkins’ mangoes. In the first one, the heat treatment consisted of immersing the fruits in a bath at 46.1 °C / 75 minutes with ethanol concentrations of 0, 5, 10 and 20% v / v, then a cooling bath at 21.1 °C / 30 minutes and stored at 25 °C. In the second, fruits were submitted to the baths, but with ethanol concentrations of 0, 3, 5 and 7% v/v, and stored at 25°C and 10°C. Physical-chemical and phytopathological analysis and percentage of mango rottenness were evaluated. Mangoes treated with more than 10% ethanol (stored at 25°C), or those treated at ethanol concentrations below 7% (stored at 10°C) did not show good external appearance. It was concluded that ethanol at the concentrations of 3, 5 and 7% v/v associated to hydrothermal treatment did not affect the quality parameters of the fruits stored at 25ºC, but these treatments decreased the mangoes shelf life, since these fruits matured faster and are not recommended for exportation.

Abstract The main objectives of this work were to study the effect of fruit ripening on the melon osmotic dehydration at reduced pressure and to model the mass transfer of moisture during melon dehydration with grape juice concentrate and sucrose solution. The ripening level had no relevant effect over the physical characteristics of the final product, with soluble solids, moisture and water activity without significant differences. Besides, the mass loss and solute gain parameters did not show significant differences, and only the solute gain had few variations. The process of the osmotic dehydration with grape juice concentrate was the most effective one, with higher dehydration and lowest solutes gain compared to the process carried out with sucrose solution. The water effective diffusivity calculated by the Fick’s equation for the process conduced with grape juice was lower than the one obtained for the sucrose solution, according to different equilibrium moisture content calculated by Peleg’s equation. The dehydrated melon with grape juice concentrate showed reduced water activity (~ 0.92) and low moisture content (~ 58%).

ABSTRACT Graviola leaves (Annona muricata L., Annonaceae) are used by some people to try to treat or even cure cancer, even though over-consumption of the fruit, which contains the neurotoxins annonacin and squamocin has caused an atypical form of Parkinson's disease. In previous analyses, the fruits were extracted with methanol under ambient conditions before analyses. In the present study, UPLC–QTOF–MS and NMR were used to analyze freeze-dried graviola leaves that were extracted using dry methanol and ethanol at 100 ºC and 10 MPa (100 atm) pressure in a sealed container. Methanol solubilized 33% of the metabolites in the lyophilized leaves. Ethanol solubilized 41% of metabolites in the lyophilized leaves. The concentrations of total phenolic compounds were 100.3 ± 2.8 and 93.2 ± 2.0 mg gallic acid equivalents per g of sample, for the methanolic and ethanolic extracts, respectively. Moreover, the toxicophore (unsaturated γ-lactone) that is present in neurotoxic acetogenins was found in the lipophilic portion of this extract. The concentrations of the neurotoxins annonacin and squamocin were found by UPLC–QTOF–MS to be 305.6 ± 28.3 and 17.4 ± 0.89 µg/g-dw, respectively, in the dried leaves. Pressurized methanol solubilized more annonacin and squamocin than ethanol. On the other hand, a hot, aqueous infusion solubilized only 0.213% of the annonacin and too little of the squamocin to be detected. So, graviola leaves contain significant amounts of the neurotoxins annonacin and squamocin, as well as some potentially healthy phenolic compounds. Finally, the potential neurotoxicity of whole leaves in dietary supplements could be much higher than that of a tea (hot aqueous infusion) that is made from them.

O comportamento reológico de polpa de umê, com 6, 7, 8 e 9 °Brix, foi avaliado utilizando-se um viscosímetro rotacional nas temperaturas de 15 a 75 °C. Modelos reológicos de Herschel-Bulkley e Ostwald-Waele (Lei da Potência) foram ajustados para se obterem os parâmetros reológicos para a polpa de umê. A viscosidade da polpa de umê foi descrita como independente com o tempo e apresentou valores de 1,9 Pa.s a 15 °C e 1,1 Pa.s a 65 e 75 °C, para polpas com 9 °Brix. O produto apresentou comportamento não-newtoniano e o modelo reológico de Herschel-Bulkley descreveu o seu comportamento. A energia de ativação variou de 6,6 a 10,6 kJ.mol-1. O índice de consistência foi mais influenciado pelo teor de sólidos solúveis totais, comparado com a temperatura, com valores de 18,0 a 22,9 Pa.s n, para polpa com 9 °Brix, e de 8,3 a 12,2 Pa.s n, para polpa com 8 °Brix, para temperaturas entre 15 e 75 °C. Os modelos reológicos apresentaram elevado índice de correlação para os dados obtidos no presente trabalho.

The rheological behaviour of mume pulp at 6, 7, 8 and 9 °Brix was investigated using a rotational viscometer at temperatures ranging from 15 to 75 °C. The rheological models of Herschel-Bulkley and Ostwald-Waele (Power Law) were fitted to obtain the rheological parameters of the mume pulp. The product was described as time non-dependent and presented a viscosity of 1.9 Pa.s at 15 °C and 1.1°Pa.s at 65 and 75 °C for the 9 °Brix pulp. The pulp showed non-Newtonian behaviour and the Herschel-Bulkley model was used to describe this behaviour. The activation energy ranged from 6.6-10.6 kJ.mol-1 and the consistency index from 18.0-22.9 Pa.s n for the 9 °Brix pulp and 8.3-12.2 Pa.s n for the 8 °Brix pulp at temperatures varying from 15 to 75 °C. The models presented high correlation values for all the rheological data obtained in the present work.

The use of antibiotics in agriculture is limited when compared to their applications in human and veterinary medicine. On the other hand, the use of antimicrobials in agriculture contributes to the drug resistance of human pathogens and has stimulated the search for new antibiotics from natural products. Essential oils have been shown to exert several biological activities including antibacterial and antifungal actions. The aim of this study was to determine the activity of 28 essential oils from medicinal plants cultivated at CPMA (Medicinal and Aromatic Plants Collection), CPQBA/UNICAMP, against Colletotrichum gloeosporioides (Penz.) Sacc., the anthracnose agent in yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg), as well as evaluating their effect in the control of post-harvest decay. The oils were obtained by water-distillation using a Clevenger-type system and their minimal inhibitory concentrations (MIC) determined by the micro-dilution method. According to the results, 15 of the 28 essential oils presented activity against Colletotrichum gloeosporioides, and the following four oils presented MIC values between 0.25 and 0.3 mg/mL: Coriandrum sativum, Cymbopogon citratus, Cymbopogon flexuosus and Lippia alba. The evaluation of Cymbopogon citratus essential oil in the control of post-harvest decay in yellow passion fruit showed that the disease index of the samples treated with the essential oil did not differ (P < 0.05) from that of the samples treated with fungicide. The present study shows the potential of Cymbopogon citratus essential oil in the control of the anthracnose agent in yellow passion fruit.

A determinação do valor de esterilização de alimentos de baixa acidez em autoclaves compreende uma minuciosa avaliação das instalações e utilidades da fábrica, uma validação do equipamento de processo térmico (através de ensaios de distribuição de calor) e, finalmente, ensaios de penetração de calor no produto. A intensidade do processo térmico aplicado ao alimento pode ser expressa pelo valor de Fo (valor de esterilização, em minutos, para uma temperatura de referência de 121,1 °C e índice térmico, z, de 10 °C, para esporos de Clostridium botulinum). Com frequência, por questões de segurança, é adotado o valor mais baixo de Fo, obtido nos ensaios de penetração de calor, como indicativo da intensidade mínima do processo aplicado. Este valor mais baixo de Fo deve ser sempre maior que o Fo mínimo recomendado para o alimento em questão. Porém, a utilização do valor de Fo da lata mais fria não explica estatisticamente todas as ocorrências práticas nos processos de tratamento térmicos em alimentos. Procurou-se desenvolver um novo enfoque para determinação do valor do Fo mais baixo, que passa a ser chamado de Fo crítico. O Fo crítico é baseado num modelo estatístico para interpretação dos resultados dos ensaios de penetração de calor em embalagens e depende não só dos valores de Fo obtidos no ponto mais frio da embalagem e no ponto mais frio do equipamento mas também do tamanho do lote de embalagens processado na autoclave, do tempo total de processo na autoclave e do tempo entre CIP (Cleaning in Plant) da autoclave. Neste trabalho procura-se explorar os resultados de medidas físicas utilizadas na validação de processos térmicos de alimentos. Para ilustrar a metodologia desenvolvida e introduzir o conceito de Fo crítico no processamento de conservas, foram preparados três exemplos de cálculo.

The determination of the sterilization value for low acid foods in retorts includes a critical evaluation of the factory's facilities and utilities, validation of the heat processing equipment (by heat distribution assays), and finally heat penetration assays with the product. The intensity of the heat process applied to the food can be expressed by the Fo value (sterilization value, in minutes, at a reference temperature of 121.1 °C, and a thermal index, z, of 10 °C, for Clostridium botulinum spores). For safety reasons, the lowest value for Fo is frequently adopted, being obtained in heat penetration assays as indicative of the minimum process intensity applied. This lowest Fo value should always be higher than the minimum Fo recommended for the food in question. However, the use of the Fo value for the coldest can fail to statistically explain all the practical occurrences in food heat treatment processes. Thus, as a result of intense experimental work, we aimed to develop a new focus to determine the lowest Fo value, which we renamed the critical Fo. The critical Fo is based on a statistical model for the interpretation of the results of heat penetration assays in packages, and it depends not only on the Fo values found at the coldest point of the package and the coldest point of the equipment, but also on the size of the batch of packages processed in the retort, the total processing time in the retort, and the time between CIPs of the retort. In the present study, we tried to explore the results of physical measurements used in the validation of food heat processes. Three examples of calculations were prepared to illustrate the methodology developed and to introduce the concept of critical Fo for the processing of canned food.

A peroxidase e a polifenoloxidase estão relacionadas com o escurecimento de frutas, por isso o controle das atividades destas enzimas é de grande importância para a tecnologia de alimentos. Neste trabalho estudaram-se as atividades dessas enzimas nas uvas frescas das cultivares Benitaka e Rubi, bem como as suas termoestabilidades e as suas atividades enzimáticas residuais no suco e nas geléias (extra e light). Foi também avaliada a qualidade microbiológica dos produtos elaborados. As atividades da enzima POD, tanto da fração solúvel quanto da ionicamente ligada, foram semelhantes nas uvas das duas variedades, Benitaka e Rubi. A atividade da enzima polifenoloxidase foi maior na variedade Rubi. As operações de cocção e pasteurização foram mais eficientes para baixar as atividades enzimáticas residuais da POD e PPO quando aplicadas às geléias de uva, em comparação com o suco. Embora não foram suficientes para a total inativação enzimática, essas operações reduziram-nas consideravelmente, e foram eficientes para garantir seguridade microbiológica dos produtos, geléias e suco.

Peroxidase (POD) and polyphenoloxidase (PPO) are oxidative enzymes related to the darkening process suffered by fruits. Thus, the control of the effects of these enzymes, in the preservation of fruit, in order to minimize the darkening process is considered of great importance for food processing technology. The present study investigated the effects of POD and PPO on fresh grapes from Benitaka and Rubi cultivars, as well as the thermal stability and the residual enzymatic activities in the processing of juice and jelly (extra and light). Moreover, the microbiological quality of the processed products was evaluated. It was observed that, the effect of the POD enzyme, from the soluble fraction, as well as from the ionically bound fraction, was similar in both varieties of grapes, Benitaka and Rubi. But the effect of the PPO enzyme was higher in the Rubi variety. Operations such as cooking and pasteurizing were the most efficient processes to reduce the residual enzymatic effect of POD and PPO in grape jelly, in comparison to the juice. Although such processes were not enough for total enzymatic inactivation, they permitted a considerable reduction, thus were efficient to guarantee the microbiological safety of the products, such as jelly and juice.

O objetivo deste trabalho foi recuperar e fracionar as proteínas do soro de leite por meio da técnica de coacervação, utilizando o polissacarídeo carboximetilcelulose sódica (CMC). O soro de leite foi obtido da fabricação industrial do queijo tipo frescal. Foram estudados concentrações do polímero (0,1% a 0,9% CMC p/v) e valores de pH, a fim de se obter uma precipitação seletiva das proteínas do soro de leite, sendo as condições otimizadas para produção em piloto. Mediante ajuste gradual, foi possível obter, no pH 3, uma precipitação das proteínas totais (PT/CMC); no pH 4, da beta-lactoglobulina (beta-Lg/CMC) e, no pH 3,2, a maior proporção de alfa-lactoalbumina (alfa-La/CMC). Os coacervados foram separados, por aplicação de força centrífuga, e caracterizados em relação à composição centesimal e perfil eletroforético. O maior rendimento foi verificado no fracionamento da beta-lactoglobulina, com 86% de recuperação dessa classe de proteínas do soro desnatado. O coacervado beta-lactoglobulina-CMC (beta-Lg/CMC) apresenta maior conteúdo protéico, provavelmente em conseqüência da proporção estabelecida entre os hidrocolóides coacervados. O coacervado composto pela alfa-La/CMC apresentou menor conteúdo protéico e porcentagem de recuperação dessas proteínas presentes no soro.

This work aimed to recover and fractionate milk whey proteins through the coacervation technique, using sodium carboxymethyl cellulose (CMC) polysaccharide. Milk whey was obtained from the manufactured cheese type "frescal". Polymer concentration (0.1-0.9% CMC w/v) and pH values were studied in order to obtain a selective precipitation of whey proteins; conditions were optimized to pilot scale production. After pH gradual adjustment the precipitation of total proteins (PT/CMC) was achieved for pH 3; for pH 4 beta-lactoglobulin (beta-Lg/CMC) precipitation and for pH 3.2 the greatest proportion of alpha-lactoalbumin (alpha-La/CMC) precipitation. Coacervates were separated by centrifuge force, and characterized in relation to their composition and electrophoretic profile. The highest yield was obtained from fractionation of beta-Lg/CMC with precipitation of 86% of this whey protein type. Highest protein content was showed by beta-Lg/CMC, probably due to the proportion among hydrocolloids. The alpha-La/CMC showed minor protein content and yield recuperation of this whey protein fraction.