Valorization of whey through development of a spray-dried fruit beverage powder: Process optimization and quality assessment

Abstract

This study aimed to optimize a refreshing whey-based pineapple beverage formulation and convert the optimized formulation into a shelf-stable powder by spray-drying. Whey was produced from milk by heating (85°C for 5 min), coagulation (1.0 % citric acid), filtration, and centrifugation, while pineapple-juice was extracted, filtered, and pasteurized. Whey, juice, and beverages were characterized for physicochemical and functional properties. Whey contained TSS 8.0°B, pH 6.00, 0.77% protein, 4.78% lactose, 0.21% acidity, and TPC 6.39 mg GAE/100 mL, whereas pineapple-juice showed TSS of 10.3°B, pH 3.8, 0.58% acidity, 12.38% carbohydrates, and 84.86% moisture. Increasing pineapple juice (10 to 50%) decreased beverage protein (0.69-0.39%) and pH (5.78−1.90) while increased acidity (0.247–0.395%) and TSS (8.23–9.15°B). 70:30 whey-pineapple formulation achieved the highest overall-acceptability (8.0). This formulation was spray-dried with maltodextrin (2.5–7.5%), inlet-air temperature (150–170°C), and feed-flow (6–10 mL/min) using 17-run BBD to optimize yield, moisture, solubility, and bulk-density. The responses varied as 37.63–46.79% yield, 2.28–4.39% moisture, 91.54–99.04% solubility, and 0.27–0.401 g/cm 3 bulk-density; quadratic-models were highly predictive (R 2 ≈0.984–0.996). Optimal conditions (169°C, 6.6% maltodextrin, 10mL/min) produced powder with 44.84% yield, 3.58% moisture, 97.6% solubility, and 0.393g/cm3 bulk-density, supporting whey valorization into instant beverage-powder with improved handling and potential nutritional utility.