Response surface modeling and optimization of extraction time, temperature, and cashew nut-to-water ratio for cashew nut milk extraction

The demand for plant-based milk alternatives has increased in recent years due to concerns related to human nutrition and environmental sustainability. Among plant-based milk products, cashew nut milk has gained considerable attention because of its nutritional value, distinctive flavour, desirable mouthfeel, and recognition as a premium product. However, variations in extraction methods often result in inconsistencies in milk quality. Therefore, this study was conducted to determine the optimum extraction conditions for cashew nut milk production. A central composite design (CCD) within response surface methodology (RSM) was employed to optimize extraction time (X1), extraction temperature (X2), and cashew nut-to-water ratio (X3) for the extraction of cashew nut milk. Milk yield, physicochemical characteristics, proximate composition, and sensory properties were evaluated using standard analytical methods. The results revealed that extraction time, extraction temperature, and cashew nut-to-water ratio significantly influenced (P < 0.05) the yield, physicochemical properties, proximate composition, and sensory attributes of cashew nut milk. Among these factors, the cashew nut-to-water ratio had the greatest influence, affecting all measured responses except pH. The optimized extraction conditions were 13 min extraction time, 60 °C extraction temperature, and a 1:1 cashew nut-to-water ratio, resulting in an optimum milk yield of 84.43%. The findings of this study indicate that maintaining a cashew nut-to-water ratio not exceeding 1:1 is essential for producing cashew nut milk with consistent and desirable quality attributes.