Effects of Simulated Circulation Temperature Changes on the Flavor of Lentinula edodes during Storage

To investigate the effects of three circulation methods including normal temperature, cold chain, and broken cold chain on the flavor substances of fresh Lentinula edodes before and after storage and transportation, the changing trends of volatile flavor compounds and taste components of L. edodes during simulated transportation under the three temperature conditions were analyzed using an electronic nose, gas chromatography-ion mobility spectrometry (GC-IMS), an electronic tongue, high performance liquid chromatography (HPLC), and an automatic amino acid analyzer. The results showed that electronic nose was able to quickly distinguish between the aroma characteristics of L. edodes under different simulated temperature conditions. In total, 55 volatile compounds were detected by GC-IMS, including 16 alcohols, 10 aldehydes, 8 terpenes, 6 ketones, 4 esters, and 11 other compounds. The electronic tongue revealed differences in the sourness, bitterness, astringency, umami, richness, and saltiness among early storage and transportation (control), simulated normal temperature logistics (NTL), simulated cold chain logistics (CCL), and simulated broken chain logistics (BCL), with the CCL group being characterized by moderate sourness and prominent umami. In the NTL, CCL, and BCL groups, the total amounts of free umami amino acids were 90.82, 81.83, and 84.31 mg/g, respectively, and the 5’-nucleotide contents were 122.99, 107.42, and 118.27 μg/g, respectively. Among them, the volatile flavor compounds and taste components in the CCL group were most similar to those in the control group, indicating that consistent low-temperature conditions are helpful for preserving the flavor quality of L. edodes during storage and transportation. In contrast, the BCL group, which experienced temperature fluctuations during both storage and transportation, exhibited slightly lower flavor quality than did the CCL group due to the negative impact on the flavor compounds before entering the shelf life. In conclusion, in the post-harvest circulation process of L. edodes, cold-chain transportation is needed to minimize quality deterioration caused by temperature fluctuations during storage and transportation. The results provide valuable insights for improving the cold chain distribution system for L. edodes.