Effect of Smoke Duration on Compositional Analysis, Deterioration Criteria, Microbial Profile and Sensory Attributes of Marine and Freshwater Fish: A Comparative Study

Abstract

Smoked fish is considered one of the most commonly consumed aquatic food. The impact of fish smoking technology on the quality criteria varies depending on the smoking time and/or temperature as well as the type of fish used. This study focused on studying the effect of using three different hot smoking durations (30, 45, and 60 min.) on different quality attributes of both marine fish (Epinephelus marginatus) and freshwater fish (Lates niloticus) during chilled storage (4ºC) under vacuum packaging for three months. Results revealed that 60 min. smoking of fish fillet achieved the best quality results as it increased the phenolic substances that resulted in a marked decline in the lipid oxidation criteria. Furthermore, increasing the smoke duration significantly decreased the microbial count of the total anaerobic sporeformers, Staph aureus count, and mold counts to below the detectable limit (<2 log10 CFU/g) while the aerobic plate count reached 2 log10 CFU/g by 60 min smoking in both fishes. Moreover, protein and salt content increased by increasing smoking time, while moisture and the available water (aw) content decreased. Sensory evaluation revealed that 45 min. and 60 min. smoking had the best sensory score compared to 30 min. smoking. All measured attributes increased gradually during chilled vacuum storage.