The effects of microwave treatment (454 W for 5 s) on the physiology and quality of minimally processed bok choy were
investigated for 9 days at 5 ± 0.5 °C. The treatment significantly reduced the respiration rate by 12% compared with that of
untreated samples, although the rates increased during storage. Microwaving prevented incipient etiolation and transpiration,
maintained relatively high − a/b value, chlorophyll content as well as low chlorophyllase activity and decay index during
storage. The treatment also decreased the relative electrolyte leakage, superoxide anion radical (
O2
·−) production rate and
malondialdehyde content compared with those of control. Furthermore, microwaving reduced the phenylalanine ammonialyase,
peroxidase activities and total phenolic contents by 17, 20 and 15%, respectively, after 9 days of storage. In contrast
to the soluble solid content, the ascorbic acid content in microwave-treated bok choy was slightly lower than that of control.
These results suggested that the immediate microwave treatment (at 454 W for 5 s for example) could decrease respiration
rate, retard etiolation and decay, improve cell membrane integrity, and therefore maintain a better quality of bok choy, which
provides a sustainable alternative for thermal physical technologies and chemical agents.

EB00000003120K

Available

• Effects of microwave treatment on physiology and quality of minimally processed bok choy (Brassica campestris L.) during storage at 5 °C