UV-C treatment inhibits browning, inactivates Pseudomonas tolaasii and reduces associated chemical and enzymatic changes of button mushrooms

Authors: WANG, XUEQING - Tianjin University; HE, XINGXING - Tianjin University; WU, XINLING - Guangxi University; WANG, FENGLING - Tianjin University; LIN, QIONG - Chinese Academy Of Agricultural Sciences; Fan, Xuetong; GUAN, WENGIANG - Tianjin University

Submitted to: Journal of the Science of Food and Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/18/2021
Publication Date: 11/19/2021
Citation: Wang, X., He, X., Wu, X., Wang, F., Lin, Q., Fan, X., Guan, W. 2021. UV-C treatment inhibits browning, inactivates Pseudomonas tolaasii and reduces associated chemical and enzymatic changes of button mushrooms. Journal of the Science of Food and Agriculture. https://doi.org/10.1002/jsfa.11668.
DOI: https://doi.org/10.1002/jsfa.11668

Interpretive Summary: Button mushroom is the most common edible mushroom species in the U.S. and the world, and browning is the main cause of quality losses of the product, affecting consumer purchase. Postharvest technologies that reduce the development of browning are needed. In the study, we applied various doses of ultraviolet C to mushroom and assessed severity of browning along with enzymatic, chemical, and microbial attributes during 21-day storage at 4 degree C. Results showed that UV-C reduced populations of bacteria responsible for chemical and enzymatic changes and consequent browning, indicating that UV-C treatment has a potential to delay the development of browning. The study provides valuable information for mushroom growers and processors to minimize the mushroom loss.

Technical Abstract: This study evaluated the effects of ultraviolet-C (UV-C) treatment on the inactivation of Pseudomonas tolaasii (P. tolaasii) in vitro and in vivo and on the disease resistance of button mushrooms during storage for 21 days at 4 degree C. Results showed that UV-C doses of 0.5-9.0 kJ/m2 resulted in 3.91-6.26 log10 CFU/mL reduction of P. tolaasii populations in vitro, and UV-C treatment reduced P. tolaasii populations inoculated on mushroom cap surfaces and browning severity. In addition, P. tolaasii increased polyphenol oxidase (PPO) activity, and decreased phenylalanine ammonia-lyase (PAL) activity, the accumulation of phenolics and contents of brown melanin precursors, including '-L-glutaminyl-4-hydroxybenzene (GHB), '-L-glutaminyl-3,4-dihydroxybenzene (GDHB), and tyrosine in button mushrooms. UV-C treatment reduced the changes due to P. tolaasii infection. These results indicated that the application of UV-C treatment inhibited browning, inactivated P. tolaasii and reduced associated chemical and enzymatic changes of button mushrooms during cold storage.