Fuente: Foods - Revista científica (MDPI) Foods, Vol. 15, Pages 1875: Consumer Rejection Threshold of Mung Bean Protein Hydrolysate: Unsweetened and Sweetened Brewed Teas as Test Models
Foods doi: 10.3390/foods15111875
Authors:
Kanokwan Promjeen
Niramon Utama-ang
Witoon Prinyawiwatkul

Mung beans (Vigna radiata L.) can be considered an environmentally sustainable food due to their nutritional value, environmental benefits, and their potential in reducing reliance on animal-based proteins. Mung bean protein hydrolysate (MBPH) is a plant-based functional ingredient; however, its application in beverages is restricted by intense bitterness. This study was the first one to determine the consumer rejection threshold (CRT) of MBPH in three beverage matrices [water, unsweetened brewed tea (USBT), and sweetened brewed tea (SBT)] to evaluate how sweetness modulated bitterness perception and, in turn, affected consumer acceptance. Sensory evaluation was conducted with 308 consumers to evaluate acceptance of overall quality and bitter taste (yes/no), hedonic rating (overall liking and liking of taste and bitterness; a 9-point hedonic scale), and preference (a 2-alternative forced-choice, 2-AFC test) of three beverage matrices across MBPH concentrations of 0.0–1.2% (w/v). Acceptance decreased with increasing MBPH concentration across all matrices, with distinct differences in CRT values among samples. Based on overall acceptance, CRT values were 0.40% MBPH for water, 0.48% MBPH for USBT, and 0.80% MBPH for SBT. CRT values based on bitterness liking were lower (0.18–0.64%) compared to those (0.24–0.76%) based on overall taste and overall liking, indicating that bitterness perception was the primary driver of rejection. The 2-AFC results showed consistent preference for control samples; therefore, CRT could not be determined using this method under the experimental condition in this study. Overall, CRT values increased from 0.18–0.48% MBPH for USBT to 0.64–0.80% MBPH for SBT, demonstrating a quantitative shift associated with matrix composition and the presence of sweetness, providing a practical strategy for product developers to enhance the palatability of plant-based beverages containing MBPH.