The Effects of vacuum packaging and some additives to extending shelf life of ground meat

The aim of this study is extending shelf life of chilled ground meat. The ground meat samples were prepared with control, 2% salt, 2% salt + 500 ppm ascorbic acid, 2% salt + 100 ppm NaN02. After vacuum packaging, samples were storaged at ±1°C for 45 days. The pH, moisture, protein.TBA, nitrite content; Total Aerobic Bacteria, psychrotrophic and coliform bacteria numbers detection and colour analysis were examined at days 0, 7,14, 21,28, 35,45 of study. The pH degree of samples were decreased during the storage. The most decreased was occured in the sample with 2% salt + 500 ppm ascorbic acid. The TBA values of samples which is indicate lipid oxidation were increased with 45 day storage and at the end of study the TBA values of control, 2% salt, 2% salt + 500 ppm ascorbic acid, 2% salt + 100 ppm NaN02 were 0.691, 0.861, 0.453, and 0.562 mg malonaldehyde/ kg respectively. Salt was catalysis of lipid oxidation, contrary of salt ascorbic acid and nitrite were decreased lipid oxidation cause of their antioxidative characteristic. The total aerobic bacteria numbers of samples were 6.55, 5.8, 5.9, 5.72, log cfu/g, the psychrotrophic bacteria numbers 4.265, 3.75, 3.87, 3.64 log cfu/g, and the coliform bacteria numbers were 5.44, 4.62, 4.73, 4.31 log cfu/g respectively. The bacteria numbers of the sample with 2% salt + 100 ppm NaN02 was lowest as antimicrobial characteristic both of salt and nitrite.The colour parameters of lightness (L*) were increased during the storaged and were occured 52.21, 46.19, 50.89,47.76, respectively. The redness (a*) of samples were increased at the end of day 7 and were observed with 18,93, 20.23, 19.59,19.30, respectively. The a* values of control and sample with %2 salt were decreased cause of lipid oxidation. The a* value of sample with ascorbic acid and nitrite were stable for 45 day as their antioxidative characteristics. At the end of the study all of the samples were acceptable with their chemical, microbiological and colour characteristic for standarts.