Effects of a Complex Functional Ingredient Based on Beef Offal Paste and Plant Ingredients on the Quality, Fatty Acid Profile, Texture, and Storage Stability of Meat Cutlets

This study developed a complex functional ingredient based on beef offal paste, whey, rapeseed and sunflower cake powder, and flax flour, and evaluated its effect on beef cutlets formulated with 0, 5, 10, and 15% additive. The study examined chemical composition, pH, water activity, functional and technological properties, color, fatty acid profile, texture, sensory quality, and refrigerated storage stability. The additive improved the nutritional profile of the cutlets by increasing the protein content from 16.20% in the control to 17.78% at the highest inclusion level, while reducing fat content from 12.50% to 11.20%. The lipid fraction also became more favorable, as total polyunsaturated fatty acids increased from 7.03% to 13.34%, and α-linolenic acid appeared only in additive-containing samples. The additive also modified the functional and structural characteristics of the products. The 10% formulation showed the most pronounced improvement in texture, with the highest hardness, gumminess, and chewiness values, while sensory quality remained comparable to the control at 5 and 10% inclusion but declined at 15%. During 7 days of refrigerated storage, additive-containing samples showed lower acid and peroxide values than the control, together with a slight reduction in microbial growth. Overall, the developed additive acted as a multifunctional ingredient that improved nutritional and technological quality. Among the tested formulations, the 10% inclusion level provided the best balance between quality, storage stability, and sensory acceptability.