Abstract
This study presents the development of an innovative technology for the national Kazakh fermented milk product “Kurt” utilizing secondary dairy raw materials (buttermilk and whey) combined with horse fat. The research addresses the dual challenges of implementing zero-waste production principles in the dairy industry while enhancing the nutritional value of traditional products. Comprehensive physicochemical, microbiological, and nutritional analyses were conducted on raw materials, intermediate products, and finished goods. Buttermilk protein precipitate demonstrated high protein content (11.51 ± 0.70%) with a favorable amino acid profile dominated by proline (1.83 ± 0.48%), leucine/isoleucine (1.34 ± 0.35%), and lysine (1.22 ± 0.42%). Whey powder exhibited significant mineral content, particularly calcium (1578.33 mg/100 g) and magnesium (172.35 mg/100 g). Horse fat (subcutaneous “zhal” type) showed a favorable fatty acid profile with oleic acid (31.59%), palmitic acid (28.10%), and significant levels of polyunsaturated fatty acids including α-linolenic acid (6.04%). The developed technology incorporates horse fat as a protein-fat emulsion at concentrations of 1%, 2%, 3%, and 5% (final concentration), introduced into the curd mass prior to molding and drying. The 3% formulation demonstrated optimal characteristics with moisture content of 11.83 ± 0.19%, protein content of 40.99 ± 0.64%, fat content of 12.05 ± 0.24%, and water activity of 0.645 ± 0.021, ensuring microbiological stability. Sensory evaluation (15 trained panelists, 9-point hedonic scale) confirmed that the 3% emulsified fat incorporation preserved the traditional fermented milk flavor while enhancing nutritional value and structural properties (overall acceptability: 7.8 ± 0.4 vs. 6.9 ± 0.5 for control). The developed technology offers a sustainable approach to dairy processing, reduces waste, and creates a value-added product with enhanced nutritional profile suitable for modern functional food applications.