In pursuit of greater practicality in the food preparation, in recent years there has been a considerable growth of researches in the field of cooling and freezing of food. Therefore, the trade in frozen food has been very promising, allowing a great variety of products to the consumers due to the convenience of transportation, storage and use. Cooling and freezing of products are preservation methods used in the food industry to maintain the sensorial attributes and nutritional properties of these products. In this sense, in order to optimize the process and reduce energy costs, this work presents a transient three-dimensional mathematical modeling to describe the heat transfer inside liquid materials with parallelepiped shape including phase change (liquid-solid) term. The governing equation was solved numerically using the finite volume technique with a fully implicit formulation. As an application, the methodology was used to predict heat transfer during cooling, freezing and post-freezing of the Tahiti lemon pulp. Numerical results of the temperature distribution at different process instants are presented and analyzed, and temperature data at the center of the product throughout time were compared to experimental data reported in the literature and a good agreement was obtained.

Freezing is one the most efficient methods for conservation, especially, fruits and vegetables. Cashew is a fruit with high nutritional value and great economic importance in the Northeast region of Brazil, however, due to high moisture content, it is highly perishable. The numerical study of the freezing process is of great importance for the optimization of the process. In this sense, the objective of this work was to study the cooling and freezing processes of cashew apple using computational fluid dynamics technique. Experiments of cooling and freezing of the fruit, with the aid of a refrigerator,data acquisition system and thermocouples, and simulation using Ansys CFX® software for obtain the cooling and freezing kinetics of the product were realized. Results of the cooling and freezing kinetics of the cashew apple and temperature distribution inside the cashew apple are presented, compared and analyzed. The model was able to predict temperaturetransient behavior with good accuracy, except in the post-freezing period.

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A busca por alternativas para aumentar a vida útil de frutas utilizando revestimentos biodegradáveis tem crescido nos últimos anos, especialmente para frutas cujo processo de amadurecimento continua após a colheita, como no caso da banana. Objetivou-se com esse estudo avaliar a conservação de bananas ‘Prata Anã’ revestidas com fécula de mandioca e pectina, durante o armazenamento em temperatura ambiente. As bananas foram selecionadas, lavadas e revestidas com soluções de fécula e de pectina nas concentrações de 0 (controle) 2, 5 e 8% e armazenados a 25 ± 3°C por doze dias, avaliando-se a cada três dias quanto à perda de massa, cor da casca, firmeza do fruto, sólidos solúveis totais, acidez total titulável e potencial hidrogeniônico. O delineamento experimental foi inteiramente casualizado em esquema fatorial 7 x 5 (concentrações dos revestimentos x períodos de armazenamento), com três repetições. Os resultados foram submetidos à análise de variância, análise de regressão e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Os revestimentos a base de fécula de mandioca e pectina caracterizaram-se como boas alternativas para aumentar a vida útil de bananas ‘Prata Anã’. As concentrações de 5 e 8% dos dois revestimentos analisados destacaram-se na conservação de alguns atributos de qualidade dos frutos como, coloração, firmeza e sólidos solúveis totais. Considerando a relação custo/benefício o uso do revestimento à base de fécula seria mais apropriado.

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The aim of this research was to evaluate the physicochemical, microbiological and bioactive quality of ‘Araçá-Boi’ pulps exposed to Gamma Irradiation. Manual harvesting was done in the morning, using good agricultural practices, and fruits were packed in thermal boxes and transported to the ‘Laboratório de Armazenamento e Processamento de Produtos Agrícolas’ of the ‘Universidade Federal de Campina Grande’, to obtain the pulp. The ‘Araçá-Boi’ pulp was irradiated in the ‘Laboratório de Irradiação Gama do Centro de Desenvolvimento de Tecnologia Nuclear’ (CDTN), located at UFPE - Recife, PE, where three doses of Gamma Irradiation (2, 3, 4 kGy) were applied for later comparison with the non-irradiated sample (control). After irradiation, the microbiological, physicochemical parameters and the quantification of vitamin C and flavonoids were evaluated it can be observed that dose 6 is grouped in a set with differential characteristics of the other treatments, as it provided higher AA, pH, luminosity and water activity (Aw). It was observed that there was no microorganism development after irradiation in all analyzed treatments. It can be concluded that the different doses of Gamma Irradiation guaranteed the microbiological quality of the ‘Araçá-Boi’ pulp, remaining fit for consumption and in compliance with the Brazilian legislation.

O presente trabalho objetivou formular uma bebida mista de água de coco e polpa de kiwi, e realizar de teste de aceitação sensorial, caracterização físico-química e avaliação microbiológica. O experimento consistiu em quatro tratamentos: T1 – 84% de água de coco, 10% de polpa e 6% açúcar; T2 – 74% de água de coco, 20% de polpa e 6% açúcar; T3 – 64% de água de coco, 30% de polpa e 6 % açúcar; T4 – 54% de água de coco, 40% de polpa e 6% açúcar. Após a fabricação os produtos foram encaminhados para a análise sensorial com cinquenta provadores para que fosse escolhido a amostra de melhor aceitação. T4 foi o que obteve maior aceitação. A intenção de compra do produto foi de 82%. Foram avaliados, em triplicata, os aspectos físico-químicos (pH, sólidos solúveis, acidez titulável, açúcar total, redutor e não redutor e cor) e as análises microbiológicas investigou coliformes fecais, bolores e Salmonella spp. A bebida mista apresentou pH de 3,58, acidez titulável de 0,63% de ácido cítrico, sólidos solúveis de 13,5º Brix, açúcar total de 9,1% de glicose, açúcar redutor de 4,84% de glicose e açúcar não redutor de 4,10% de sacarose. As análises colorimétricas caracterizaram a bebida de baixa luminosidade, com coloração verde e intensidade amarela. Os resultados físico-químicos, juntamente com a boa aceitação sensorial e intenção de compra sugerem que a bebida mista possa ser utilizada de forma comercial.

Among several biodegradable coatings used to extend the shelf life of fresh fruits, those that can be obtained from Moringa oleifera stand out due to their extraordinary biochemical, antibacterial and antifungal properties. Another aspect is their constitution which is composed of proteins, lipids, carbohydrates, carotenoids, vitamins, minerals and natural bioactive compounds, that can be applied for the development of functional foods due to their nutritional and pharmaceutical properties. The objective of this study was to evaluate the effect of bio-based coating produced from different concentrations of Moringa oleifera seed oil added to cassava starch in the postharvest conservation of Tommy atkins mango fruits. The bio-based coating was applied to mango fruits stored at room temperature (27 °C) for 15 days. Mangoes were submitted to the following treatments: moringa oil (Moringa oleifera) in 4 concentrations: 0.5% (v/v) + cassava starch; 1% (v/v) + cassava starch; 1.5% (v/v) + cassava starch and a control treatment without coating (0%), during 15 days of storage (0, 3, 6, 9, 12 and 15 days), adding up to 24 treatments with three replications. The application of moringa-oil-based coating prolonged the postharvest shelf life of the Tommy atkins mango by maintaining the physicochemical and physical properties during 12 days of storage at room temperature when compared to control treatment. M. oleifera oil-based coatings delayed the degradation of the pigments, making the bio-coated fruits gain shine and remain with it