異硫氰酸丙酸烯酯處理對切絲甘藍(Brassica oleracea L. var. Capitata L.)酵素性褐變之影響

Shredded cabbages (Brassica oleracea L.var. Capitata group cv. Summit) were treated with allylisothiocyanate (AITC) by vacuum infiltration and fumigation. To understand the effect of AITC on the inhibition of enzymatic browning of shredded cabbages, the changes of △E, polyphenol oxidase (PPO) activity, phenylalanine ammonialyase (PAL) activity, and total phenols were measured at room temperature. Results showed that 500ppm AITC treated by vacuum infiltration resulted in 50% decrease of △E, 87% inhibition of PPO activity increase, and 64% inhibition of PAL activity increase of the cabbage 24 hours after shredding. The increase of total phenols was inhibited, too. Fumigation could also inhibit the enzymatic browning of shredded cabbage, however, vacuum infiltration was more efficient than fumigation The mechanism of the inhibition of browning could be that both the increases of PPO activity, and PAL activity of cabbage were inhibited after shredded by AITC treatment. However, the former could be more important than the latter.