Combined effect of low acid paste and modified atmospheric condition on quality changes of white shrimp, Litopenaeus vannamei during chilled storage

Antibacterial activity, total phenolic compound content, beta-carotene content and antioxidant activity of low acid paste, Tom-Yum paste was evaluated before subjected to apply to white shrimp as marinade agent. It was found that Tom-Yum paste could inhibit S. aureus, E. coli 0157:H7, L. monocytogenes and P. fluorescens with clear zone’s sizes of 21.2-24.8, 14.2-18.3, 11.2-12.6 and 7.0-9.0 mm, respectively. The beta-carotene, total phenolic compound content and IC50 value of Tom-Yum paste were 676.46±52.41 μg/g dried sample, 1.00±0.07 g catechin/100 g dried sample and 2.17±0.16 mg dried sample/ml extract solution, respectively. The shelf-life of marinated shrimp kept in normal air and modified atmospheric packagings were 15-18 and 18-21 days, respectively, while shelf-life of raw white shrimp was only 9-12 days. Using marinating and modified atmosphere condition could provide more antibacterial and antioxidant properties resulted in increased white shrimp shelf-life.