Combining Modified Atmosphere Packaging and Nisin to Preserve Atlantic Salmon

Preservation effects of modified atmosphere package combined with nisin on fresh Atlantic salmon were evaluated. Farm-raised Atlantic salmon were purchased from the local market and packaged using either 19 % CO2: 70 % N2 : 11 % O2 , 38 % CO2 : 51 % N2 : 11 % O2, and under atmospheric air (with and without nisin at 400 IU/g) resulting in a total of 6 treatments. The microbiological (aerobic plate count, psychrotrophic bacteria, and lactic acid bacteria) and the total volatile basic nitrogen analyses were evaluated on Day 0, 2, 4, 7 and 10. Package headspace and sensory evaluation were also conducted on Day 0, 2 and 4. The presence of CO2 effectively inhibited the growth of all three types of bacteria while nisin significantly inhibited the growth of aerobic microorganisms with less impact on lactic acid bacteria. The TVB-N test indicated that CO2 delayed the spoilage of Atlantic salmon while nisin had a lesser but measurable impact on Atlantic salmon shelf-life. The experiments support the potential for combining modified atmosphere package and nisin as an effective method to limit the spoilage of Atlantic salmon compare to traditional preservation methods.