Effect of sea cucumber extract (Holothuria leucospilota) on the microbial quality of Otolithes rubber fillets in refrigerated storage

In this study, Otolithes rubber fillets were treated by sea cucumber Holothuria leucospilota extraction and then they were vacuum packed. Packed fillets were refrigerated at 4 centigrade for sixteen days. As an evaluation, microbial tests every four days including counting total bacteria, Pseudomonas, Enterobacteriaceae and hydrogen sulfide-producing bacteria were done. The results declared that during the period, the sum of the total bacteria in all treatments has increased and the maximum value of this index was maintained at 12th day in all treatments. Furthermore during the storage period, the number of bacteria which produce hydrogen sulfide and Pseudomonas and Enterobacteriaceae, were significantly greater than samples which were treated by sea cucumber Holothuria leucospilota extraction. Interestingly, there were no bacteria in the samples that were treated by sea cucumber Holothuria leucospilota 2% extraction for first four days. Also Enterobacteriaceae weren’t found in 1% and 2% extraction treatments until the 8th day of storage and the bacteria producing hydrogen sulfide weren’t seen in 2%, 1% and 0.5% extraction treatment until 12th, 8th and 4th day respectively. Results indicate dramatically that sea cucumber extraction has a considerable impact on samples including maintaining quality and increasing storage time of fish fillets in cold conditions. Notably 2% extract was more effective than other extracts concentrations in increasing survival of fillets.