Diacetyl Inhibits the Browning of Fresh-Cut Stem Lettuce by Regulating the Metabolism of Phenylpropane and Antioxidant Ability

• Published in: Foods Vol. 12; no. 4; p. 740
• Main Authors: Li, Xiaotong, Zhang, Song, Wang, Qingguo, Dong, Tiantian
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.02.2023; MDPI
• Subjects: 4-Coumarate-CoA ligase; Accumulation; Ammonia; Antioxidants; Biosynthesis; Browning; browning inhibitor; Diacetyl; diacetyl fumigation; Enzymes; Enzymic browning; Experiments; Food science; Fruits; Gene expression; Lettuce; Metabolism; Phenolic compounds; Phenols; Phenylalanine; Phenylalanine ammonia-lyase; Physiological aspects; Physiology; Polyphenols; Shelf life; Stainless steel; stem lettuce slices; Stems; Vegetables; China; stem lettuce slices; diacetyl fumigation; browning inhibitor
• ISSN: 2304-8158; 2304-8158
• DOI: 10.3390/foods12040740

Enzymatic browning is the main quality issue of fresh-cut stem lettuce ( L. ). In this research, the effect of diacetyl on the browning and browning-related mechanisms of fresh-cut stem lettuce was explored. The data showed that diacetyl treatment with 10 μL L inhibited the browning of fresh-cut stem lettuce and extended the shelf life by over 8 d at 4 °C compared with the control. Diacetyl treatment repressed gene expression and decreased the activities of PAL (phenylalanine ammonia-lyase), C4H (cinnamate-4-hydroxylase) and 4CL (4-coumarate-CoA ligase), which thus reduced the accumulation of individual and total phenolic compounds. Moreover, diacetyl enhanced the antioxidant ability and reduced ROS accumulation, improving the anti-browning ability and indirectly suppressing the biosynthesis of phenolic compounds. These results indicated that diacetyl treatment repressed the browning of fresh-cut stem lettuce by regulating the phenylpropanoid metabolism pathway and antioxidant ability. This study is the first to report that diacetyl has an effective anti-browning role for fresh-cut stem lettuce.