LAUSR

BACKGROUND In this study, the effects of biofilm coatings obtained by immobilization of different borates, including borax (BX), colemanite (COL), and ulexite (UX), with chitosan (Ch) on the shelf life of rainbow trout fillets were investigated. The immobilization and characterization of borates in chitosan were confirmed by scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, and zeta potential (ζ) analysis. In determining the shelf life of fillets that were covered with immersion and stored for 15 days, microbiological (total aerobic mesophilic, psychrotrophic, lactic acid, Pseudomonas, and Enterobacteriaceae bacteria count) and chemical analyses (total volatile basic nitrogen, thiobarbituric acid reactive substance, and pH levels) were performed at 3-day periodic intervals. In addition, the biodegradation of borates was determined by inductively paired plasma mass spectrometry (ICP-MS) in biofilm-coated fillets on the 1st, 8th, and 15th storage days. RESULTS The microbial results of the coatings enriched with borates (BX, COL, and UX) at different levels (0, 0.03, and 0.06 mg L-1 ) (due to the immobilization with chitosan), the shelf life was extended by 3-6 days in all of the treatment groups compared to the control. CONCLUSION It was concluded that BX, COL and UX coatings enriched by immobilization with Ch increase shelf life and improve fillet quality. In addition, the enrichment of BX, COL, and UX with Ch showed explicit natural protective effects. This study demonstrates that Ch-enriched coatings of BX, COL, and UX can be used as natural bioactive nanocarriers to provide bioactive food ingredients in the seafood processing industry. This article is protected by copyright. All rights reserved.