Enzymatic debittering of cheese flavoring and bitterness characterization of peptide mixture using sensory and peptidomics approach

• Published in: Food chemistry Vol. 440; p. 138229
• Main Authors: Xiang, Qin, Xia, Yixun, Fang, Sicong, Zhong, Fang
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15.05.2024
• Subjects: Bitter peptides; bitterness; Bovine milk proteins; Cheese flavoring; cheeses; debittering; Enzymatic debittering; Enzyme specificity; fermentation; food chemistry; hydrolysis; hydrophobicity; milk; milk proteins; molecular weight; peptides; peptidomics; proteinases; proteolysis; quantitative structure-activity relationships; Enzymatic debittering; Bitter peptides; Cheese flavoring; Enzyme specificity; Bovine milk proteins
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2023.138229

•Peptidomics and bioinformatics detailedly characterized debittered hydrolysates.•Bitterness in peptide mixture predominantly depended on molecular mass (M).•Bovine milk protein hydrolysates achieved debittering when M below 0.5 kDa.•Debittering was evaluated by matching enzyme specificities with substrate features.•Pro, Leu, Phe, and Val specific proteases could debitter bovine milk-based products. Peptides in cheese flavoring produced through proteolysis plus fermentation generated bitterness. Bitterness of individual peptide can be quantified using quantitative structure–activity relationship, where molecular mass (M), hydrophobicity, residues, C-terminal hydrophobic amino acids (C-HAAs), and N-terminal basic ones (N-BAAs) are crucial. However, their accumulative influence on the overall bitterness of peptide mixture remains unknown. This study delved into extensive proteolysis to debitter and to correlate the multi-influencing factors of peptides and the collective bitterness. As hydrolysis increased from 7.5 % to 28.0 %, bitterness reduced from 5.0 to 0.3–2.7 scores, contingent on proteases used, in which FU was optimal. The overall bitterness cannot be predicted through the summation of individual peptide bitterness, which depended on M (0.5–3 kDa) and 5–23 residues, followed by N-BAAs and C-HAAs. Analysis of enzymatic cleavage sites and substrate characteristics revealed, to more effectively debitter bovine milk protein hydrolysates, proteases specifically cleaving Pro, Leu, Phe, and Val were desired.