Abstract:

Once plant cells are ruptured, glucosinolates (GLs) are quickly contacted with myrosinase (MYR) and degrade
into isothiocyanates (ITCs), which are believed to be anticarcinogens. Effects of cutting, steaming and dehydrating on the
contents of GLs and ITCs, and MYR activity in ‘Pate’ cabbage were studied. Results showed that the contents of total GLs
and aliphatic GLs were the lowest, and the content of ITCs was the highest when cabbage leaves were cut into 1.0 cm ×
1.0 cm pieces, a 38.91% increase over that of the intact cabbage. With increasing steaming time, MYR activity decreased.
After steaming for 60 s, the highest content of ITCs was observed, a 53.70% increase compared with the fresh cabbage,
as well as the lowest contents of total GLs and aliphatic GLs. The highest content of ITCs was obtained by addition of 5%
glucose, a 76.26% increase compared with the fresh cabbage. When the drying temperature was 50 ℃, the content of ITCs
was increased by 89.88% compared with the fresh cabbage; meanwhile, the contents of total GLs and aliphatic GLs were the
lowest. Therefore, the optimal processing conditions for cabbage were cutting into 1.0 cm × 1.0 cm pieces, steaming for 60 s,
addition of 5% glucose, and hot air drying at 50 ℃.

Key words: cabbage, glucosinolates, isothiocyanates, myrosinase, dehydration