Work

Ultrasound-assisted maillard reaction: a novel strategy for debittering, flavor enhancement, and antioxidant activity improvement of walnut peptides

Year: 2026

Type: article

Abstract: Walnut peptides (WP) possess multiple biological activities (antioxidant, anti-inflammatory, antihypertensive, immunomodulatory) and broad application prospects in functional foods, medical formulas and nutritional supplements. However, their bitterness caused by hydrophobic amino acids from enzymatic hydrolysis severely limits sensory acceptability and practical use. This study evaluated the feasibility and efficacy of ultrasound-assisted Maillard reaction (US-MR) for debittering WP. Ultrasonic pretreatment at 30% and 45% amplitudes was combined with MR, followed by systematic analysis of WP’s antioxidant activities and flavor profiles. Results showed that this treatment significantly promoted WP-glucose conjugation, decreased pH, increased free amino acid content and browning intensity, and enhanced antioxidant activity. It also facilitated the formation of diverse volatile flavor compounds (aldehydes, ketones, alcohols, thiophenes, furans, pyrazines). Sensory evaluation indicated improved aroma, umami and texture, with a marked reduction in bitterness. In conclusion, US-MR is an effective debittering method, providing a promising strategy for developing high-value WP-derived products.

Source: Food Chemistry X

DOI: 10.1016/j.fochx.2026.103958