Development and characterization of lactose-hydrolyzed whey candy
摘要
Whey represents one of the largest dairy by-product streams worldwide, retaining 55–60% of the nutrients originally present in milk, yet its high lactose content, limited solubility, and environmental disposal challenges restrict its utilization; enzymatic lactose hydrolysis using β-galactosidase improves sweetness, reduces the risk of lactose crystallization, enhances digestibility, and broadens its applicability in frozen confections. This study aimed to develop, optimize, and characterize a reduced-sugar, lactose-hydrolyzed whey-based frozen candy by determining the optimal enzyme concentration for lactose hydrolysis, evaluating the combined effects of sugar and CMC stabilizer on compositional, physico-chemical, and sensory attributes, and assessing the suitability of four flavour emulsions, orange, pineapple, kalakhatta, and jaljira. Sweet whey was hydrolyzed using Maxilact L5000 (0.2–0.4 mL/L), with 0.3 mL/L selected based on achieving ~ 85% lactose conversion; candies were formulated with four sugar levels (18–24%) and three CMC levels (0.2–0.4%) and evaluated for composition, pH, acidity, melting resistance, and sensory assessment. Lactose hydrolysis increased considerably with enzyme concentration, plateauing at 0.3 mL/L. Sugar level significantly influenced total solids, carbohydrates, acidity, melting resistance, and flavour scores, while CMC level significantly affected body, texture, and melting quality due to its water-binding and cryo-stabilizing effects. The optimized formulation, 22% sugar and 0.4% CMC, exhibited desirable composition (TS 30.75%, fat 0.15%, protein 0.75%), physico-chemical characteristics (pH 3.91; acidity 0.53% citric acid; melting resistance 82.62%), and good sensory acceptability. Among the flavours tested, orange achieved the highest consumer preference (8.70), followed by jaljira (8.40), while pineapple and kalakhatta showed comparatively lower acceptability. These findings demonstrate that reduced-sugar frozen candy can be formulated using lactose-hydrolyzed whey, enabling 35% relative reduction in sucrose without influencing sensory quality.