Abstract 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.

RESUMO O estádio de abertura floral na colheita e o uso de técnicas pós-colheita, como o revestimento das inflorescências com cera de carnaúba, podem influenciar na manutenção da qualidade para comercialização. Assim, objetivou-se avaliar o conteúdo de carboidratos em inflorescências de bastão-do-imperador colhidas em dois diferentes estádios de abertura e tratadas com diferentes concentrações da cera de carnaúba. As inflorescências foram colhidas com brácteas semiabertas (brácteas basais iniciando seu processo de expansão) e abertas (brácteas basais totalmente expandidas e abertura das brácteas menores do interior da inflorescência) e receberam a aplicação de cera de carnaúba nas concentrações 0,75%; 1,5% ou 3,0%, além de um tratamento controle, sem aplicação da cera. Após o tratamento, as hastes florais foram mantidas a 16 e 21 ° C por 20 dias. Ao longo do período de armazenamento realizaram-se cinco amostragens de brácteas (brácteas externas e internas separadamente – em inflorescências abertas; brácteas externas e internas em conjunto – em inflorescências semiabertas), a cada três dias para avaliação dos teores de açúcares solúveis totais e amido. Os teores de açúcares solúveis totais e amido diferiram entre os diferentes tipos de brácteas coletadas e ao longo do período de armazenamento avaliado, podendo indicar uma remobilização de reservas. A concentração de 3,0% de cera de carnaúba proporcionou um maior teor de açúcares solúveis totais, entretanto esse teor não interfere na longevidade do bastão-do-imperador nos dois estádios de abertura floral avaliados.

ABSTRACT Floral opening stage during harvest and use of postharvest techniques, such as inflorescence coating with carnauba wax, may influence quality maintenance for commercialization. The aim was to evaluate the carbohydrate content of torch ginger inflorescences harvested at two different opening stages and treated with different concentrations of carnauba wax. The inflorescences were harvested with semi-open (basal bracts beginning their expansion process) and open bracts (fully expanded basal bracts and opening of the smaller bracts on interior of the inflorescence) and received the application of carnauba wax at concentrations of 0.75%; 1.5% or 3.0%, in addition to a control treatment, without wax application. After the treatment, the floral stems were maintained at 16 and 21 °C for 20 days. During the storage period, five bracts samples (external and internal bracts separately - in open inflorescences, external and internal bracts together - in semi-open inflorescences) were carried out every three days for evaluation of total soluble sugars and starch content. Contents of total soluble sugars and starch differed between the different types of bracts collected and throughout the storage period evaluated, and could indicate a remobilization of reserves. The concentration of 3.0% carnauba wax induced higher total soluble sugar content. However, this content does not affect the longevity of torch ginger at the two evaluated floral opening stages.

ABSTRACT The aim of this study was to analyze the effect of colored-shade nets on the physicochemical characteristics of physalis in subtropical area. The experimental design was the randomized blocks with a 4 × 5 factorial, being four species of physalis (Physalis peruviana, P. pubescens, P. minima and P. ixocarpa) and four net colors (white, blue, red and black), besides the control under full sun. Titratable acidity (TA), pH, vitamin C, soluble solids (SS), SS/TA relation, total phenolics, anthocyanins and antioxidant capacity were evaluated. It was 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.

Com 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.

This 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.