The effect of different pre-treatments on sensory characteristics of unformulated pulse-based beverages

The objectives of this study were to evaluate the effects of specific pre-treatments-including dry milling (control), soaking-wet milling, blanching, blanching-alkaline soaking-dehulling, vacuum treatment, and germination-on the sensory and aroma characteristics of beverages (termed as milk analogues or milk substitutes) derived from chickpea, faba bean, and cowpea as primary ingredients. In line with these objectives, solid phase micro extraction-gas chromatography-mass spectrometry (SPME-GC-MS), gas chromatography-olfactometry (GCO), and descriptive sensory evaluation were conducted, coupled with principal component analysis. Hexanal, 2-pentylfuran, 1-hexanol, and 2-heptanone were the most abundant volatiles in pulse-based milk analogues regardless of the pulse type. Among them, hexanal was found in the highest amount in all types of milk analogues. Most of the pre-treatments, including blanching, which was applied to inactivate the lipoxygenase enzymes, resulted in a significant increase in hexanal content (p < 0.05). However, blanching-alkaline soaking-dehulling was the most effective treatment in reducing the off-notes. Germination of 48 h or longer contributed to the development of formation of undesirable flavours.