Changes during fermentation and properties of som-fug produced from different marine fish

Microbiological, chemical and physical changes of Som-fug produced from six marine fish during fermentation were monitored. During the fermentation (0-72 h) at 30C, the increase in lactic acid bacteria (LAB) count and total acidity (TA) with the concomitant decrease in pH was observed. After the fermentation was completed, Som-fug samples contained 1.5-7.9 x 10(9) cfu/g LAB count and TA ranging from 2.00 to 2.28% with the pH range of 4.53-4.60. Trimethylamine N-oxide content decreased, whereas trimethylamine content increased throughout the fermentation (P < 0.05). Proteolysis of Som-fug proteins and lipid oxidation occurred during fermentation. As the fermentation proceeded, hardness, adhesiveness, springiness and cohesiveness of all samples increased, and L*, a* and b* values also increased (P < 0.05). Generally, Som-fug produced from bigeye snapper showed a greater acceptability than those produced from other species. However, its acceptability was slightly lower than a commercial Som-fug produced from freshwater fish (P < 0.05).