Debittering of Red Bell Pepper ( Capsicum annuum ) Juice Retaining a High Vitamin B6 Content, Using a Styrene-divinylbenzene Adsorbent Resin

Abstract

Despite the high nutritional value of ripe red bell pepper (RBP) juice, RBP is typically considered a bitter vegetable. This excess bitterness affects the quality of RBP juice and results in rejection by consumers. We developed a manufacturing process to remove the bitter taste of RBP juice while retaining high nutrient levels. Compared to several resins, synthetic adsorbent resins had the most pronounced debittering effects, yielding the least bitter taste and green top note, while retaining a sweet taste and flavour. In particular, a styrene-divinylbenzene adsorbent resin having relatively large pores (pore radius ≥ 250 Å) removed more than 83 % of the bitterness of RBP juice, based on the quercetin-3-O-rhamnoside content. Moreover, vitamin B6 was retained at a high level, and the basic nutritional balance did not change after the treatment. The debittering effect was correlated with resin content, implying that quercetin-related flavonoids accounted for the bitter taste of RBP juice. Thus, resin adsorption is an efficient technique for the debittering and selective retention of high-value nutrition in RBP juice.