Effect of microwave assisted extraction on yield and protein characteristics of soymilk.

Microwave assisted extraction (MAE) has been investigated for its potential to aid in extraction of soymilk from soybeans. A batch type grinding cum microwave heating unit was specifically designed and developed for this purpose. MAE of soymilk has resulted in significant increase (p < 0.05) in extraction yield (24%) and protein content (44.4%) as compared to conventional soymilk. Protein characteristics such as protein solubility and protein digestibility of extracted soymilk also showed significant increase (p < 0.05) with respect to conventional milk. The influence of microwave process parameters including microwave power level (540–810W), target temperature (70–90 °C) and stirring speed (140–180 RPM) on protein characteristic of soymilk were analysed. Microwave power level and target temperature were significant (p < 0.05) parameters for the extraction process. The optimal MAE conditions were power level of 675W, target temperature of 80 °C and stirring speed of 160 RPM. • Microwave assisted extraction has been proven as an effective method to increase extraction yield and quality of soymilk. • Yield, protein content and protein solubility of soymilk was increased by 24%, 44.4% and 94.6% respectively by this method. • Microwave power and target temperature were significant for yield and quality of soymilk. • SEM imaging revealed increased breakdown of soybean cell wall structure. This attributes to the success of MAE. [ABSTRACT FROM AUTHOR]