The disposal of paneer whey, a nutrient-rich by-product of the dairy industry, poses significant environmental and economic challenges due to its high organic load despite containing valuable proteins, lactose, and minerals. The present study aimed to evaluate the feasibility of utilizing paneer whey as a complete or partial replacement for water in cookie production and to assess its effects on the sensory, nutritional, and physicochemical characteristics of the developed products. Five cookie formulations were prepared by replacing water with paneer whey at different levels (0, 25, 50, 75, and 100%), designated as T₀, T₁, T₂, T₃, and T₄, respectively. The cookies were analyzed for proximate composition, calorific value, and sensory quality using standard analytical methods.

Progressive incorporation of paneer whey significantly (P ≤ 0.05) improved the nutritional composition of cookies. Moisture content increased from 6.11% in the control (T₀) to 11.32% in T₄, while protein content increased from 9.07% to 9.92%. Fat and ash contents also increased from 22.23% to 24.53% and 0.48% to 1.09%, respectively. In contrast, carbohydrate content decreased from 62.11% to 53.15%, resulting in a slight reduction in calorific value from 484.84 to 473.19 kcal/100 g. Sensory evaluation revealed that cookies prepared with 100% paneer whey (T₄) achieved the highest scores for colour and appearance (8.45), body and texture (8.30), taste and flavour (8.15), and overall acceptability (8.30) on a nine-point hedonic scale, indicating excellent consumer acceptance.