LAUSR

BACKGROUND This study was aimed to synthesize polymeric chitosan nanoparticles (CSNPs) from Macrobrachium nipponense shells using sodium triphosphate (TPP) as a crosslinker that was incorporated with spirulina extract (SPE) to improve the shelf life of Pike- Perch during refrigerated storage (4 °C). RESULTS The encapsulation efficiency (EE) of SPE- loaded CSNPs decreased from 67% to 32%, and loading capacity (LC) was increased (10%-14%) depending on their loaded SPE concentrations. The initial burst effect, followed by a slow-release at pH =7 (24 h), was observed. Free SPE and SPE incorporated chitosan nanoparticles decreased microbial counts (TVC, total viable count; TPC, total psychotropic count; pseudomonas, and LAB, lactic acid bacteria) compared to control and unloaded chitosan nanoparticles. Samples treated with free SPE or SPE-loaded CSNPs showed higher changes in odor, color, TVB-N (Total volatile basic nitrogen), and TBA (Thiobarbituric Acid) compared with the unloaded CSNPs batch (P ≤0.05) until the 10th day of storage. However, fish fillets coated with SPE-loaded CSNPs had the highest overall consumer acceptability and the lowest values for TVB-N and TBA at the end of storage (14th day). Controlled release of bioactive compounds in batches treated with SPE-CSNPs could delay the microbial degradation and enhance chemical reactions (TBA and TVB-N) in comparison to pure SPE during storage time. CONCLUSION The incorporation of SPE in polymeric CSNPs can be considered as a promising material for controlled delivery of natural bioactive agents, and preservation of Pike perch quality during refrigerator storage. This article is protected by copyright. All rights reserved.