Effect of soybean roasting on soymilk sensory properties

Purpose The purpose of this paper is to evaluate the changes in descriptive sensory properties and overall consumer acceptability of soymilk prepared from roasted soybeans. Design/methodology/approach In total, 12 purposively selected post graduate students majoring in Food Science conducted descriptive sensory analysis after being trained for 18h in sensory analysis, while 75 untrained students conducted consumer acceptability test of soymilk prepared by roasting soybeans at a temperature of 110 degrees C for 20, 40, 60, 80 and 100min and at 120 degrees C for 20min. Findings Results have revealed that roasting soybeans improved sensory properties by significantly (p<0.05) decreasing the objectionable green, beany flavours and increasing sweet taste, viscosity and roasted flavour. Furthermore, results from the principal component analysis revealed that aroma and sweet taste were the most critical sensory attributes. In addition, it was found out that soymilk samples prepared by roasting soybeans at 110 degrees C for 40 and 60min and at 120 degrees C for 20min were significantly more acceptable than the control soymilk. Research limitations/implications The participants in this study were from one locality and predominantly soybean consuming community and therefore there is need to conduct the study in a different locality in order to validate the study findings. Practical implications The study can assist small scale processors that might not have access to lipoxygenase-free soybeans and other technologies for improving the quality of soymilk. Social implications The study can be used as a guide for connecting the food processers with the external world of consumption. Originality/value For the first time, the study findings have demonstrated that controlled soybean roasting can be a useful strategy for improving soymilk sensory properties and consumer acceptability. The findings in this study can be usefully used in the quality control of soy bean-based products.