Long-term quality retention and decay inhibition of chestnut using thymol loaded chitosan nanoparticle

Thymol (TMO) was loaded into chitosan nanoparticles (CSNPs) to inhibit chestnuts decay during storage. Three chestnut treatments were evaluated, including the CK (uncoated control), CSNPs (coated with chitosan nanoparticles), and TMO-CSNPs (coated with thymol-loaded chitosan nanoparticles). Quality assessments of chestnuts were conducted periodically for up to 180 days, which included starch content, amylase activity, water content, respiration rate, weight loss rate, microbiological indicators, decay rate, and quality evaluation. Results indicated that TMO-CSNPs had significantly less nutrient loss in soluble sugar (10.61%) and starch content (27.72%) compared with CK, which was attributed to low metabolic activities as evident in low amylase activity and respiration rate. Moreover, TMO-CSNPs significantly inhibited the growth of mold and yeast (4.17 log CFU g^-1 on day 180) and kept the lowest decay rate (5.33%). This study demonstrates the potential of food nanomaterial as an alternative strategy to promote food security and supply chain resilience.