The influence of packaging methodology on the microbiological and fatty acid profiles of refrigerated African catfish fillets

Aims: The shelf-life of refrigerated catfish fillets was determined at 2 de greesC, to simulate retail conditions, using two types of packaging materia ls, vacuum packing (VP) and oxygen permeable packaging (OPP). Methods and Results: Representative samples (n = 5) from both types of pack aging methods were drawn at random every 2 d until a microbiological count of 10(6) cfu g(-1) n as reached. Samples were pooled and screened microbiol ogically using standard methods. Fatty acid analyses of total lipids, neutr al lipid, glycolipid and phospholipid fractions were also conducted, to det ermine at which point the fish was regarded as spoiled and which packaging method provided a longer shelf-life. OPP limits storage to a maximum of 4 d (aerobic plate count of 8.2 x 10(5) cfu g(-1)), whereas VP extends the she lf-life of the fillets to between 6 and 8 d (aerobic plate count of 9.2 x 1 0(4) cfu g(-1) and 1.66 x 10(6) cfu g(-1), respectively). Similarly, colifo rm counts increased with time; however, packaging material had no statistic al influence thereon. Conclusions: Until d 13, when the experiment was terminated, no deteriorati on in lipid composition of the various fractions was noted. Significance and Impact of the Study: An extended shelf-lift: microbiologic ally-speaking, for potential processors, could thus be obtained by using VP instead of OPP.