The effect of light salting, vacuum packaging and their synergistic effecton on shelflife of rainbow trout (Oncorhynchus mykiss) fillet during storage at 4°C±1

Salting and vacuum packaging، each of them has disadvantages for fish preservation in non-frozen mode. This study was aimed to investigate the The effect of light salting، vacuum packaging and their synergistic effect on on shelflife of rainbow trout (Oncorhynchus mykiss) fillet during storage at 4°C±1. For this purpose the rainbow trout fillets were brined in 10 salt solution and vacuum packaged. Measuring of PH، total volatile bases nitrogen compounds (TVB-N)، tiobarbitoric acid (TBA)، total viable microbial count (TVC) and sensory evaluations، were performed during 18 days in refrigerator temperature. Obtained results showed that all of chemical and microbial indices increased during storage period. PH، TBA and TVB-N indices and microbial growth in salted، vacuum packaged was lower than other treatments and in light salted treatment was lower than control group (p<0. 05). The results of sensory evaluations showed that light salting of rainbow trout fillet situation improved these indices rather than control group. Salted vacuum packaged treatments had a better sensory evaluations scores than salted treatment (p<0. 05). with regarded to allowable restrict of TVB-N indices (25 mg/100g fillet) and total viable count (6 Log cfu/g) and also sensory evaluations، light salting and salted vacuum package treatments increased the shelflife of rainbow trout fillet in 4°C about 3 and 7 days، respectively and the major problems of each method of salting and vacuum packaging was removed.