Effects of vacuum and modified atmosphere packaging on the shelf life of Rohu fish (Labeo rohita) stored at refrigerated temperature (4°C)

Abstract

Vacuum packaging and modified atmosphere packaging (MAP) are important techniques used for the extension of fish and fish product’s shelf life. The present work evaluated the quality and shelf life of Rohu fish (Labeo rohita) by biochemical and microbiological analyses under different packaging types namely (1) unsealed pack (control), (2) vacuum pack, (3) MAP-1 (50% CO2 and 50% N2), and (4) MAP-2 (50% CO2 and 50% O2) at 3-day intervals during 18 days of refrigerated storage (4°C). Result showed that pH, total volatile base nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) values for all packaging conditions were within the acceptable limit during the storage period, except for TBARS value in MAP-2 sample. The total viable count (TVC) gradually increased with the progress of time in all packaging conditions. However, the TVC values were significantly (p<0.05) lower on 9th and 12th day of storage in MAP samples as compared to that of the control sample. Considering the total bacterial counts, 7 log CFU/g, the shelf life was determined at approximately 8, 11, 13, and 16 days for control, vacuum pack, MAP-1, and MAP-2 sample, respectively. Therefore, MAP is recommended to be used to display and preserve fishes in the superstores.