observed that P. peruviana and P. pubescens have more acid fruits, and P. minima shows vitamin C content higher than the other species. In general, fruits of P. peruviana and P. pubescens have better quality when grown in white, blue or black shade net; fruits of P. minima are physicochemically superior when produced under full sun or under white or blue shade net; finally, fruits of P. ixocarpa have low quality when produced under black net.

The objective of this paper was to evaluate the effect of bioactive whey protein isolate/montmorillonite films containing citric acid on the inhibition of enzymatic browning and physicochemical properties in minimally processed apples. Whey protein isolate films incorporated with montmorillonite (3 g/100 g) and citric acid (5 and 10 g/100 g) were applied to the apples slices. All samples were packaged in polypropylene trays (14.6 cm × 11.4 cm × 6.5 cm) and stored at 5 ± 2 °C and 85 ± 3% RH for eight days. Every two days, the apples samples were evaluated for color, acidity, pH, soluble solids, water activity and polyphenol oxidase and peroxidase enzyme activity. The enzymatic browning of the apples slices was reduced for all films during storage. However, the films containing citric acid maintained the color characteristics, reducing the loss of quality associated the maintenance of acidity, soluble solids, water activity, reduction of polyphenol oxidase and peroxidase activity, thus prolonging the shelf life of the apples.

Pepino japonês (Cucumis sativus L.) submetido ao tratamento... 487Ciênc. agrotec., Lavras, v. 30, n. 3, p. 487-493, maio/jun., 2006 RESUMOCom o presente trabalho objetivou-se avaliar a qualidade e a vida útil do pepino (Cucumis sativus L.), utilizando recobrimento com película de fécula de mandioca. Após seleção, amostras de pepino japonês foram mergulhadas em suspensões de fécula de mandioca a 0, 2, 3 e 4%, secos ao ar e armazenados em câmara fria a 5ºC e 95% de UR por 8 dias. As análises realizadas foram perda de massa, pH, sólidos solúveis (SS) , acidez titulável (AT), Cor L*a*b e firmeza. O delineamento utilizado foi o DIC com 3 repetições, com os tratamentos dispostos em esquema fatorial 4 x 5. O valor encontrado para firmeza nas amostras tratadas com película a 4% foram menores em comparação aos outros tratamentos, isto, provavelmente se deve à plasticidade do tecido que estas amostras apresentaram. A película reduziu significativamente a perda de massa das amostras mantidas sob refrigeração. A aplicação de película de fécula de mandioca na concentração mais elevada (4%), proporcionou ao pepino um aspecto melhor de conservação, tornando o produto mais atraente. Termos para indexação:Cucumis sativus L., biofilme, pós-colheita. ABSTRACTThis work was made to evaluate the properties and postharvest life of cucumber (Cucumis sativus L.) coated with cassava starch film. After the selection the fruits were dipped in suspensions 0, 2, 3 and 4% starch, dried naturally and stored in chamber cold (5ºC ± 1ºC and 90% ± 5% HR) during 8 days and the analyses were done in the time zero and in intervals of 2 days. The analyses done were loss mass, titratable acidity (TA), pH, soluble solids (SS), color L*a*b and firmness. The test was conducted in completely randomized design, with three repetitions, with the treatments disposed in factory layout 4x5. The value found for firmness in the samples treated with biofilm at 4% was smaller in comparison to the other treatments, this, is probably due to the plasticity of the tissue that these samples presented. The film reduced the loss of mass of the samples maintained under refrigeration significantly. The application cassava starch film in the highest concentration (4%), provided to the cucumber a better aspect of conservation, turning the most attractive product.

No abstract

The objective herein was to evaluate the effect of processing, packaging type (with and without exposure to light) and storage time on the quality of functional attributes of jelly prepared from curriola pulp. The experimental design was a completely randomized 2 × 5 factorial design, with two levels of packaging (transparent and amber) and five storage periods (0, 3, 6, 9 and 12 months). In general, the processing of curriola pulp determined a slight increase in phenolic compounds and antioxidant activity and a reduction in vitamin C content of freshly prepared jelly. The amber package and storage time promoted higher retention of bioactive compounds, mainly gallic acid, besides reducing the percentage of jelly oxidation, determined by the β-carotene / linoleic acid antioxidant method. A reduction in phenolic compounds and vitamin C was observed, which caused a reduction in the antioxidant capacity of curriola jelly. Of the five phenolic compounds identified in freshly prepared curriola jelly, gallic acid was identified as the major compound. In addition, the use of amber packaging, which prevents the incidence of light, may favor the maintenance of bioactive compounds during storage period of curriola jelly under environmental conditions.

The purpose of this study was to determine the effect of thermal vacuum processing and thermal processing without vacuum on the content of bioactive compounds and the antioxidant activity of low-calorie mixed Brazilian cerrado fruit jam. The mixed jam consisted of 60% of mixed pulp of Marolo, soursop and sweet passion fruit, and 40% other ingredients. This jam was utilized a completely randomized design to evaluate the antioxidant activity, total phenolic profile and content, carotenoid profile, and ascorbic acid content. The results showed that there was a reduction in bioactive compounds in the jam of 44.37% for total phenolics, 50.56% for ascorbic acid, 78.40% total carotenoids, and 65.14% for antioxidant activity when compared with the mixed pulps. In the carotenoid profile, reduction was observed for all compounds in relation to the mixed pulps, especially β-carotene (average loss of 81.89%). Independent of the processing, there was a significant increase in m-coumaric acid in the jam compared with the mixed pulp. The concentrations of other phenolic compounds decreased after processing. These results suggest that thermal vacuum processing is most suitable for the production of jam with higher nutritional value.

Programas de melhoramento do morangueiro tem buscado aprimorar atributos de qualidade, aumentar a produtividade bem como reduzir custos de produção. O desenvolvimento e a caracterização de novos materiais são fundamentais para alavancar a cultura no país, assim como atender a demanda dos consumidores quanto aos aspectos de aparência e propriedades químicas do fruto. Objetivou-se com o presente trabalho analisar as propriedades físico-químicas de híbridos experimentais de morangueiro, visando à caracterização e seleção de genótipos mais promissores para o mercado in natura e para o processamento, a partir de genótipos do programa de melhoramento genético da Universidade Federal de Lavras. As características avaliadas foram: teor de sólidos solúveis (SS), acidez titulável (AT), firmeza de polpa, açúcares totais, pectina solúvel, pectina total, pH, SS/AT, tamanho, formato e coloração externa e interna do fruto. As análises foram realizadas em 103 híbridos experimentais e sete cultivares comerciais. Conforme a caracterização, os híbridos MOGSC12-501, MCA12-86, MDA12-37 e MFA12-448 destacaram-se principalmente para as variáveis: firmeza de polpa (2,18 a 2,79N) e para SS/AT com valores entre 10,93 a 11,85%, apresentando elevado potencial para comercialização quando comparados as cultivares comerciais normalmente plantadas no Brasil.Palavras-chave: Fragaria x ananassa Duch. Melhoramento do morangueiro. Pós-colheita.Physico-chemical properties of experimental hybrid fruit strawberry. The strawberry breeding programs are seeking for quality attribute improvement, increase yield as well as reduce the production costs. The characterization of the newly released materials is very important in order to understand and explore the external aspects and chemical parameters of the fruit. The objective of this work was to measure the physicochemical properties of experimental strawberry hybrids, aiming at the characterization and selection of the most promising genotypes for the in natura market and for the processing, from genotypes the breeding program of the Universidade Federal de Lavras, according to the evaluate characteristic: soluble solids (SS), titratable acidity (TA), firmness, total sugars, soluble pectin, total pectin, pH, ratio SS/TA, size, shape and external and internal colour of the fruit. The experiment design was a completely randomized with 103 hybrid and seven commercial cultivar. According to the characterization, hybrids MOGSC12-501, MCA12-86, MDA12-37 and MFA12-448 stood out mainly for the variables: pulp firmness (2.18 to 2.79 N) and for SS/AT ranging from 10.93 to 11.85%, presented high potential for commercialization when compared to commercial cultivars usually planted in Brazil.

This study evaluated the impact of processing, packages (amber and transparent glass jars), and storage time on the stability of the bioactive compounds (total phenolic compounds and vitamin C), and antioxidant activity of mangaba jelly. Jelly processing, significantly (p < 0.05) decreased the bioactive compounds and antioxidant activity. The storage time, significantly (p < 0.05) influenced all the variables studied in this work, although they were not affected by packages. A significant decrease of the bioactive compounds and antioxidant activity was observed during the jelly storage. HPLC-DAD/UV-Vis analyses allowed to identify 10 phenolic compounds, including flavonoids and non-flavonoids, and among these, quercetin and catechin were the major compounds. After processing, all these compounds decreased significantly (p < 0.05), except for the gallic acid and the p-coumaric acid, which presented an increasing tendency. During jelly storage, only gallic acid, caffeic acid, catechin, and rutin were affected. Despite the reduction in the antioxidant activity and bioactive compounds studied, mangaba jelly retained good levels of them and may be considered a potential novel functional food.