Effect of iced storage of bigeye snapper ( Priacanthus tayenus) on the chemical composition, properties and acceptability of Som-fug, a fermented Thai fish mince

Abstract

The effect of iced storage of bigeye snapper ( Priacanthus tayenus) on the chemical composition, properties and acceptability of Som-fug was investigated. During 15 days of iced storage, total volatile base (TVB), trimethylamine (TMA) and TCA-soluble peptide contents as well as thiobarbituric reactive substances (TBARS) of fish muscle increased continuously after 3 days of storage ( p < 0.05). It was suggested that deterioration, protein degradation and lipid oxidation proceeded with increasing storage time. Som-fug prepared from surimi of bigeye snapper stored in ice for different times had similar pH, acidity and lactic acid bacteria count at the end of the fermentation (30 °C, 48 h). Generally, higher content of TCA-soluble peptides and higher TBARS were found in fermented Som-fug produced from bigeye snapper stored in ice for a longer time ( p < 0.05). Hardness, adhesiveness, springiness, cohesiveness, and resilience of fermented Som-fug decreased with a concomitant increase in weight loss, released water and expressible water contents when fish kept for a longer time were used ( p < 0.05). L ∗, a ∗, b ∗, whiteness and the likeness for appearance, colour, texture and flavour of Som-fug decreased when fish kept in ice for an extended time were used ( p < 0.05). However, the taste likeness was not affected by iced storage time ( p > 0.05). No differences in overall liking were noticeable when fish kept in ice for up to 12 days were used for Som-fug production ( p > 0.05). Therefore, the quality of fish used as raw material should be an important factor in determining the characteristics of Som-fug.