Efficiency of Dry Ice and Ice Combination on Improving the Quality and Shelflife of Seerfish (Scomberomorus commersonii) Steaks

Abstract

Seerfish (Scomberomorus commersonii) steaks stored in a combination of dry ice and ice at a ratio of 1:0.2:0.5 (fish:dry ice:ice) and in dry ice at a ratio of 1:1 (fish:dry ice) were found to be in good quality and sensorialy suitable for consumption when they were stored for 24 h and 30 h, respectively, without reicing. When fish steaks were stored in ice at a ratio of 1:1 (fish:ice) as control, they were in good condition only up to 18 h. Total bacterial load ranged from 105 to 10 8 cfu . g, while total psychrophiles was from 102 to 105 cfu . g. Total lactics and H2S producers were found to be 101 to 104 cfu . g. Total histamine formers were from 102 to 104 cfu . g. Total coliforms were 1600 MPN . g at the end of the storage period. The TMA-N contents were within the limit of acceptability. Histamine contents varied from 0 to 20 ppm. A lowest temperature (–11.9°C) was observed in steaks stored in dry ice. Highest level of CO2 was recorded in steaks stored in both the dry ice and combination of dry ice and ice. Staphylococcus constituted 37% of the flora in fresh fish followed by Proteus, Pseudomonas, Aeromonas, Bacillus, Alcaligenes, Micrococcus, Acinetobacter and Flavobacterium. Pseudomonas was the dominant flora in both the dry ice-stored and combination of dry ice and ice-stored steaks while in control pack, Proteus was dominant. Thus, a combination of dry ice and ice improved the quality and increased the shelf life of fish steaks by about 6 h compared to ice alone.