EVALUATING THE FRESHNESS OF LITOPENAEUS VANNAMEI THROUGH THE DETERMINATION OF HISTAMINE INDEX BY HPLC AND QUALITY INDEX METHOD (QIM)

Abstract

In this paper, we present a method for determining histamine in Litopenaeus vannamei using HPLC. Histamine is derivatized with o-phthalaldehyde (OPA) precolumn and measured by fluorescence detector. Chromatographic conditions are investigated and the solvent for histamine extraction from shrimp is also considered in this study. The results show that the mobile phase containing 80% etanol, a linear concentration range of 55 ppb – 330 ppb, and a derivatization reaction time of 10 minutes are optimal. Notably, etanol solvent exhibits higher efficiency in histamine extraction (%H = 81,95%) than the commonly used metanol (%H = 46.29%). Based on our findings, we propose a method for determining histamine in Litopenaeus vannamei using HPLC. Quality Index Method (QIM) is utilized for sensory quality assessment of Litopenaeus vannamei stored at 0°C for 10 days, and the quality index (QI) is recorded according to the storage date. The freshness of Litopenaeus vannamei is estimated by a classification level based on a combination of histamine content and QI.