L-methionine inhibits yellowing of peeled water chestnuts (Eleocharis tuberosa) and improves their quality and texture

Yellowing and the quality (total soluble solid (TSS), titratable acid (TA), ascorbic acid (AA)) and texture decline are the main reasons for shortening the storage period of peeled water chestnuts (PWCs). The mechanism of l-methionine (L-Met) inhibiting the yellowing of PWCs and improving their quality and texture is still unknown. The goal of this study was to elucidate the mechanism of l- Met-inhibiting the yellowing of PWCs and improving their quality and texture. PWCs were treated with 0.6 %, 1.2 % and 1.8 % l-Met. The degree of yellowing, polyphenol oxidase (PPO) activity, peroxidase (POD) activity, phenylalanine lyase (PAL) activity, TSS content, TA content, AA content, texture and microorganism of PWCs were measured during storage. Compared to the control, 1.8 % l-Met-inhibited POD activity by 90.03 %, TA content by 14.55 %, and the hardness by 100.89 % on day 12. These results indicated that l-Met-decreased the yellowing by inhibiting POD activity, improved the quality by inhibiting TA content, and improved the texture by inhibiting the hardness. l-Met-can be used to prolong the storage period of PWCs.