Preservation of Minced Meats by Using Medium and High-Dose Levels of Gamma Irradiation

摘要

The effect of medium (2.5-10 kGy) dose irradiation and high (20-70 kGy) dose irradiation on the microbiological, chemical and organoleptical properties of minced meat samples was studied. It was found that irradiation dose of only 5 kGy greatly reduced all microbial counts and completely eliminated all non-spore forming pathogenic bacteria contaminated minced meat samples. Consequently, this irradiation dose extended the refrigerated (3℃ ± 1) storage life of these products for more than 8 weeks. This irradiation dose almost did not affect the chemical composition, particularly the main amino acids and main fatty acids of minced meat samples. Panelists could not differentiate between irradiated minced meat samples at this dose and unirradiated samples. High doses irradiation, i.e. 40 and 70 kGy were sufficient and efficient for sterilizing minced meat samples and in obtaining long-stable minced meat products (two years) at ambient temperature. These irradiation doses slightly reduced (not more than 7%) aspartic acid, glutamic acid, methionine and lysine of minced meat. It also decreased the relative percentage of total unsaturated fatty acids by not more than 17%. These high irradiation doses caused loss of C18:3 and C20:1.