Effect of biopreservation combined with modified atmosphere packaging on qualities of chilled pork

Air packaging group as the control, at 4℃ cold storage, single preservative (ε-polylysine) and compound preservative ( ε- polylysine, chitosan, tea polyphenols) combined with modified atmosphere packaging on qualities of chilled pork were done the total number of bacteria, total volatile base nitrogen (TVB-N) , pH, redness value (a*) and water holding capacity were determined to evaluate combination with two kinds of preservation methods in the preservation. The results showed that shelf life of air packaging group was about6 d, shelf life of chilled pork that deal with ε-polylysine and compound preservative were about 10 d and 16 d respectively. Biopreservative combined with modified atmosphere packaging can significantly extended the shelf life of chilled pork, but the preservation effect of the vacuum-packed package was poor. The sample with80% CO2+20% O2 had the best antibacterial effect and lowest TVB-N. Till at 20 th day, the samples with complex preservative were still in good freshness standards, but they had worse color and water-holding capacity. Air composition of 20% CO2+80% O2 had the worst antibacterial effect. The shelf life was complex preservative experimental group about 19 d, but with the better effect on color, The shelf life 50% CO2+50% O2 had better effect on antibacterial activity, color protection and water retention.