Abstract
This study evaluated the effect of electron beam irradiation (EBI) on the quality, safety, and storage stability of suzbe (a high-moisture curd semi-finished product) and kurt (a dried curd product). Suzbe samples were irradiated at doses of 0.3, 0.5, and 0.7 kGy and stored at 2–4 °C for 20 days. Kurt samples were irradiated at 1, 3, and 5 kGy and stored at 20 °C for 180 days. Non-irradiated samples served as controls. Irradiation at 0.3 kGy (suzbe) and 1 kGy (kurt) suppressed spoilage microflora, including yeasts, and maintained chemical composition and amino acid profiles without significant losses. Higher doses (≥3 kGy) caused a significant reduction ( p < 0.05) in methionine (17.5%), tryptophan (21.1%), and lysine (18.6%). EBI improved water-holding capacity (WHC) and fat-holding capacity (FHC), reduced syneresis, and stabilized water activity (aw) and pH. Microstructural analysis revealed compaction of the kurt matrix at 1 kGy and loosening of the suzbe structure at higher doses. No pathogenic microorganisms were detected in any samples. EBI at optimal doses (0.3 kGy for suzbe, 1 kGy for kurt) is a promising non-thermal technology to extend shelf life and preserve the quality of traditional fermented dairy products.