Quality assessment of mustard hilsa (Tenualosa ilisha) in various packing conditions during storage at low temperatures

Abstract

Biochemical, microbiological and sensory quality parameters of mustard hilsa prepared from Hilsa
shad (Tenualosa ilisha) were examined to observe the changes in quality during storage at refrigeration
temperature (5° to 8°C) for 60 days and at frozen temperature (-18°C to -20°C) for 180 days. The moisture,
protein, lipid, and ash content and pH value in mustard hilsa decreased compared to those obtained for fresh
fish. On the other hand, TVB-N and peroxide values increased compared to the values found in fresh fish. At
refrigeration temperature and frozen temperature moisture and ash contents increased but protein and lipid
content decreased gradually throughout the storage period. pH value of the mustard hilsa reduced from 7.22
to 6.01 and 6.59 at refrigeration and frozen temperatures, respectively. The TVB-N value and peroxide value
increased progressively throughout the storage period irrespective of storage temperatures. Rate of changes in
different parameters of mustard hilsa was slower in vacuum sealed packs than non-sealed and sealed packs.
The aerobic plate count of bacteria was increased in refrigeration temperature but the load of microbes was
reduced at frozen temperatures. The result of sensory quality change showed that, irrespective of storage
temperature and packing condition the scores of sensory quality parameters decreased with the progress of
storage time though the decreasing rate was slower at frozen temperature. The study concluded that, at
refrigeration temperature mustard hilsa might remain in acceptable condition up to 60 days and at frozen
temperature for about 180 days in vacuum sealed pack.