Changes in sensory quality of sterile cantaloupe dice stored in controlled atmospheres.

Diced cantaloupe flesh that was microbiologically sterile was prepared in order to study the physiological deterioration of fruit when stored under a range of controlled atmospheres at 4.5°C. Sterile fruit pieces were prepared by boiling whole melons for 3 min, then dicing aseptically. Storage atmospheres were in continuous flow and contained from 0 to 26% CO2 and 3.5 to 17% O2. Sensory assessments were carried out by a highly trained panel at 14-day intervals. Products that were acceptable for up to 28 days were obtained when the following 3 treatments were used: 6% CO2 and 6% O2; 9.5% CO2 and 3.5% O2; and 15% CO2 and 6% O2. Overall, treatment with 0, 19.5 or 26% CO2 (irrespective of O2 concn.) caused significant deterioration in sensory properties

Respiratory activity and browning of minimally processed sweet potatoes Atividade respiratória e escurecimento de raízes de batata-doce minimamente processada

Sweet potatoes (Ipomoea batatas L.), 'Brazlândia Roxa', 'Brazlândia Branca' and 'Princesa' were harvested at optimum maturity to evaluate respiratory activity and browning susceptibility of minimally processed roots. After harvest, non-blemished roots were graded for size (18&plusmn;2cm) and diameter (5&plusmn;1cm), and minimally processed inside a cold room. Processed roots were placed in sealed glass jars and stored at 3&plusmn;0.5&deg;C to evaluate respiratory activity during a 4-hour period or were packed in plastic films with partial vacuum to evaluate development of browning. Packages were stored under refrigerated conditions (3&plusmn;0.5&deg;C) for 5 days. Daily, minimally processed roots were evaluated for browning according to a scale ranging from 0 (extremely browned) to 5 (no browning) and using an objective assay (absorbance at 340 nm). Minimally processed roots showed a pronounced increase in carbon dioxide evolution immediately after processing. 'Princesa' had the highest respiratory activity among the evaluated cultivars, being 40% higher two hours after processing than the other cultivars. 'Brazlândia Roxa' and 'Brazlândia Branca' were significantly less susceptible to browning compared to 'Princesa', which was rated as unacceptable for commercial use at the end of the storage period. 'Brazlândia Roxa' and 'Brazlândia Branca' were still marketable at the end of the storage period.<br>Batata doce (Ipomoea batatas L.), 'Brazlândia Roxa', 'Brazlândia Branca' e 'Princesa' foram colhidas no ponto ótimo de maturidade hortícola, com o objetivo de avaliar-se a atividade respiratória e a suscetibilidade ao escurecimento de raízes minimamente processadas. Após a colheita, raízes sem danos mecânicos aparentes foram selecionadas para tamanho (18&plusmn;2cm) e diâmetro (5&plusmn;1cm) e foram minimamente processadas no interior de uma câmara fria. As raízes minimamente processadas foram colocadas em frascos de vidro hermeticamente fechados e armazenados a 3&plusmn;0,5&deg;C para avaliar-se a atividade respiratória durante um período de 4 horas. Porções de raízes minimamente processadas (&plusmn;300 g) foram armazenadas em filmes plásticos com vácuo parcial para avaliação do desenvolvimento de escurecimento. As embalagens foram armazenadas sob refrigeração (3&plusmn;0,5&deg;C) por 5 dias. Diariamente, as raízes minimamente processadas foram avaliadas para escurecimento de acordo com uma escala de notas variando de 0 (extremamente escurecido) a 5 (sem escurecimento) e utilizando um método objetivo (absorbância a 340 nm). As raízes minimamente processadas apresentaram um aumento pronunciado na atividade respiratória logo após o processamento. A cultivar Princesa apresentou a maior atividade respiratória dentre os materiais estudados, possuindo uma atividade respiratória 40% superior às demais cultivares, 2 horas após o processamento. As cultivares Brazlândia Roxa e Brazlândia Branca foram significativamente menos suscetíveis ao escurecimento quando comparadas com "Princesa", que possuía qualidade comercial inaceitável ao final do período experimental. Por outro lado, as cultivares Brazlândia Roxa e Brazlândia Branca ainda possuíam qualidade comercial ao final do experimento