Obtaining higher yield and quality rapeseed protein: complex enzymatic hydrolysis assisted alkaline water extraction of cold pressed-extracted rapeseed meal

In this experiment, rapeseed meal (RSM) was subjected to different pressing temperatures (75 °C and 150 °C) and extraction method (enzymatic hydrolysis (EH), alkaline water extraction (AWE), and EH + AWE) were chosen to assess the effects of temperature on nutritional components, protein solubility (PS), secondary structure, fractions, and molecular weight (PMW), and in vitro protein digestibility (IVPD) of RSM and various methods on the extraction rate (ER), yield, and the characteristics of rapeseed protein (RP). The results indicated that high temperature caused some proteins to remain bound within the fiber, reduced PS and α-helix content, thereby complicating the extraction process. The RP extracted using EH + AWE showed higher ER, yield, PS, small PMW, and soluble sugar, lower glucosinolate content. This study established that EH + AWE of cold pressed-extracted RSM is a suitable method for RP extraction, providing a reference for the efficient development of RSM and the application of RP in the food industry.