No abstract

No abstract

No abstract

Lettuce (Lactuca sativa L.) is a leaf vegetable rich in vitamins, minerals, fiber and bioactive compounds. Its preservation after harvest usually occurs under refrigeration, slowing the chemical and microbiological reactions. The objective of this study was to verify the influence of the refrigeration parameters (set temperature and oscillation range) on the preservation of hydroponic crispy lettuce (Lactuca sativa L.), variety Solaris, in terms of weight loss and moisture, vitamin C and total chlorophyll contents. Samples were analyzed during 14 days of storage packed in expanded polystyrene (EPS) packaging wrapped with polyvinyl chloride (PVC). Different conditions of set temperature (2 °C, 6 °C and 10 °C) and oscillation range (±1 °C, ±3 °C and ±5 °C) were tested, using a 3² experimental design. The analysis revealed losses in the mass and moisture content after 14 days, with the greatest reductions being observed for the treatments with a set temperature of 10 °C and all oscillation ranges (±1 °C, ±3 °C and ±5 °C). However, the vitamin C and total chlorophyll contents showed variations during storage for all treatments studied. Based on the results of this study, it was concluded that applying a low temperature (2 °C), with all 3 oscillation ranges studied, can prolong the lettuce shelf life.

RESMUMOO morango é um pseudofruto não climatérico que após a colheita possui curta shelf-life. Dentre os fatores responsáveis pela perda de qualidade dos morangos estão a alta atividade metabólica e alta susceptibilidade ao ataque microbiano, principalmente por fungos. Esta pesquisa tem como objetivo analisar a estabilidade físico-química de morango (Fragaria vesca L.) submetido a condições de refrigeração não isotérmicas. As amostras foram armazenadas em temperaturas de 2 ºC e 6 ºC e amplitudes de ± 1 ºC, ± 3 ºC e ± 5 ºC, acondicionadas em bandejas de polietileno tereftalato (PET) cristal, envolta por filme de policloreto de vinila (PVC). As amostras foram avaliadas quanto aos seus aspectos físico-químicos: variação de massa, teor de vitamina C, teor de umidade, cinzas totais, pH, sólidos solúveis, teor de polifenóis totais e atividade de água (aw), sendo os ensaios realizados em triplicata. Utilizouse o software Statistica 7.0 para tratamento dos resultados obtidos através do teste de Tukey, em nível de 5% de significância estatística. Os resultados demonstram que a 6 ºC ± 3 ºC foi a melhor condição de armazenamento para a manutenção da qualidade dos morangos durante 6 dias de armazenamento, pois nestas condições obteve-se menor variação de massa, de vitamina C e de atividade de água. Estes parâmetros estão associados à redução da perda de umidade, o que auxilia na conservação do teor de cinzas totais, pH, sólidos solúveis e polifenóis totais. Palavras-chave:Morango; Shelf-life; Refrigeração; Parâmetros Físico-Químicos. Brazilian Journal of DevelopmentBraz. ABSTRACTStrawberry is a non-climatic pseudofruit and after harvest has a short shelf-life. Among the factors responsible for the quality loss of strawberries are the high metabolic activity and high susceptibility to microbial attack, especially by fungi. This project aims to study the physicochemical stability of strawberry (Fragaria vesca L.) under different refrigeration conditions. Strawberries were stored at temperatures of 2 °C and 6 °C and amplitudes of ± 1 ºC, ± 3 ºC and ± 5 ºC, stored in polyethylene terephthalate (PET) crystal trays wrapped by polyvinyl chloride (PVC) film. The samples were evaluated for their physicochemical aspects, such as: mass variation, vitamin C content, moisture content, total ash, pH, soluble solids, polyphenols and water activity, and all tests were performed in triplicate. Statistica 7.0 software was used to treat physicochemical results by Tukey test, at 5% level of statistical significance. The results show that at 6 °C ± 3 °C it is better to maintain the strawberries quality stored for 6 days, because under these conditions there was less variation in mass, vitamin C and water activity. These parameters are associated with low moisture loss, which aids in the conservation of total ash content, pH, soluble solids and polyphenols. A espécie de morango Fragaria vesca L. tem origem europeia. É uma planta rasteira, da família das rosáceas, que possui folhas ovaladas e flores de pétalas brancas. Os verdadeiros frutos do mor...

Refrigeration and coating of active biopolymers are two potential approaches to extending the shelf life of fresh fruits. Thus, the aim of this study was to test the influence of storage temperature (5 and 10 °C ± 1 °C) and whey concentration (edible coating), on functional, physical-chemical, and microbiological characteristics of acerola stored for 12 days. Edible coatings were produced using whey (30% and 60%) and glycerol. Samples were compared to a control (no coating), during storage at both temperatures. Storage at 10 °C improved the maintenance of the acerola color, while storage at 5 °C increased the stability of vitamin C and decreased microbial growth (p ≤0.05). The application of edible coating reduced the total color variation and degradation (a*) at both temperatures. The concentration of whey influenced significantly (p≤0.05) on the vitamin C content (A10-60), and on the mesophilic (A5-60 and A10-60) and psychrotrophic bacteria (A10-60) counts.

No abstract

No abstract