Quality Characteristics of Cold Stored Fresh Beef Sausage Formulated with Incorporation of Wheat Germ and Treated by Gamma Rays

Abstract

The quality characteristics of fresh beef sausage formulated with incorporation of wheat germ and treated by gamma rays were studied during cold storage. Samples of fresh beef sausage were formulated by incorporation of wheat germ at level of 10%. The prepared sample were exposed to gamma rays at doses of 0 ,3 and 4.5 kGy and the quality characteristics were examined every 3 days during refrigerated storage of samples at 4±10C. Samples of irradiated and non-irradiated sausage were highly acceptable for their sensory properties. Irradiation of samples significantly decreased their total bacterial count and molds and yeasts counts, while total psychrophilic bacterial and coliform bacteria were not detected in all irradiated samples. All microbial counts showed gradual increases during cold storage of samples but the rate of increases was lower in irradiated samples except coliform bacteria which were not detected in all irradiated samples during their cold storage. On the other hand, cold storage induced gradual decreases in the values of PH for all non-irradiated and irradiated samples, meanwhile the contents of total volatile basic nitrogen (TVBN) and thiobarbituric acid (TBARS) gradually increased in all sample under investigation during their cold storage. A significantly drop in the counts of
Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis in irradiated samples, with no levels detected over the storage time. The bacteria count of control (non-irradiated) samples, on the other hand, gradually increased, demonstrating the limited efficacy of cold storage alone. Additionally, Bacillus cereus was completely suppressed by 4.5 kGy gamma irradiation, although 3 kGy treatment
markedly inhibited its growth in comparison to the control. Salmonella spp. count was not detected in any of the samples. Irradiation of beef sausage at doses of 3 and 4.5 kGy extended the refrigerated shelf life of sample of 18 and 21 days respectively compared to 6 days for the non-irradiated samples. It is recommended to use 4.5 kGy gamma-irradiation to enhance cold-stored fresh beef sausage with wheat germ for the best overall outcomes. The product's safety is ensured by eliminating major microbial hazards, such as Bacillus cereus. Bacterial, yeast, and mold growth is significantly reduced during cold storage, and the cold storage shelf life is extended to 21 days at 4 ± 1 °C while maintaining acceptable sensory qualities (color, odor, taste, and texture). Thus, for fresh beef sausage, this dosage achieves the best possible mix of shelf-life extension, microbiological safety, and sensory quality during cold
storage.