Effect of prolonged storage in ice on nutrient composition and sensory quality of whole fresh pond raised tilapia fish (Oreochromis shiranus)

Abstract

A study was conducted to determine the effect of prolonged storage in ice of fresh pond raised Tilapia fish (Oreochromis shiranus) on its nutrient composition and quality. Live fish were collected from Bunda College Fish Farm ponds and stored in clean block ice. Sensory, proximate and pH analyses were conducted at a three day interval to determine changes in nutrient composition and quality of the fish while kept in ice. Crude protein and crude fat decreased significantly (P<0.05) while ash increased significantly (P<0.05) with storage time in ice. pH increased with storage time in ice (R2=0.815). Fish remained in acceptable freshness condition up to day 15 while highest sensory demerit score was recorded on the 18th day suggesting complete rejection. Sensory demerit scores of the fish increased with storage time in ice (R2=0.886) indicative of a decline in acceptability with storage time in ice by the sensory panel. This study demonstrated that fleshly harvested Oreochromis shiranus from ponds stored in ice can remain acceptable for purchasers for up to 15 days. This is an advantage especially to rural small scale fish farmers who can hardly afford to preserve their fresh fish in refrigerators but may locally access ice. However, there is need for future research to assess the microbiological load to ascertain safety of the product beyond 15 days storage period.