Alterações sensoriais em alface hidropônica cv. Regina minimamente processada e armazenada sob refrigeração

Abstract

Com o aumento da demanda por frutas e hortaliças minimamente processadas, a manutenção da qualidade destes produtos é um fator fundamental. O consumidor exige um produto fresco, de aspecto saudável, com boas características de cor, bem como outros atributos desejáveis na sua aparência. Foram avaliadas algumas alterações sensoriais em alface hidropônica, cv. Regina, minimamente processada, acondicionada em sacos plásticos termosoldados e armazenadas a 2ºC e 10ºC. Independente da temperatura de armazenamento, até o terceiro dia, nenhum comprometimento do produto houve para qualquer dos aspectos de qualidade analisados: cor, frescor, escurecimento da nervura central, escurecimento de bordas, aspecto de podre e sabor de cozido. No armazenamento a 2ºC a alface apresentou uma vida de prateleira de sete dias, sem comprometimento das suas principais características de aparência, ou seja, não houve escurecimento e a cor e o frescor se mantiveram inalterados. Para o produto armazenado a 10ºC, as alterações ocorridas tornaram o produto indesejável após o terceiro dia.

Quality of fresh-cut avocado (Persea americana Mill.) stored under different temperatures

“…It can also be observed, in Figure 7, that on the 3rd day of storage the product stored the 0 o C presented lower firmness than the fruits under 10 o C however, these presented a firmness statistically equal to the product at 5 o C. Starting from the 3rd day of storage the halves stored at 5ºC presented, on average, higher firmness than the others (0 and 10 o C), which presented statistically equal firmness until the end of the storage. Flitsanov et al, (2000), working with storage of intact avocados under different temperatures, observed that during four weeks of storage under low temperatures (2 and 4ºC) there was an insignificant decrease in the firmness of the fruits, which presented firmness equal to 89.2 N and 79.2 N, respectively, until the fourth week of storage, while, the fruits under higher storage temperatures (6 and 8ºC) altered their firmness more significantly to 12.5 N and 10.9 N, respectively, at the end of this period. Such results, demonstrate that the lowering of the temperature is efficient in the maintenance of the firmness and, consequently, in the increase of the postharvest life of vegetables in natura, as long as the low temperature tolerance limits for each species and/or cultivar are respected, avoiding the damage caused by the cold.…”

“…These methods, such as environmental control or modification, the use of wax on the surface of the products, chemical additives, among others, does not produce good results if they are not associated to the use of low temperatures (Chitarra and Chitarra, 2005). Flitsanov et al (2000), working with storage of intact avocados under different temperatures observed that avocados stored at 6 and 8ºC softened more quickly than those stored at 2 and 4ºC.…”

Activity of enzymes associated with the enzymatic browning of minimally processed potatoes

“…Temperatures above the recommendation influence the browning degree. Freire Junior et al (2002) reported that the temperature of 2 o C was effective in avoiding the browning in minimally processed lettuce until the 10th day of storage, which did not happen at 10 o C. In view of the factors mentioned above, given the importance of the potato crop for the Brazilian agribusiness and the lack of studies on the enzymatic browning of minimally processed potatoes, the purpose of the present work was to evaluate the effect of different potato cultivars and storage temperatures on the enzymatic metabolism of minimally processed potatoes.…”