Peanut allergen reduction and functional property improvement by means of enzymatic hydrolysis and transglutaminase crosslinking

Authors: SHI, MENG - Mississippi State University; TAN, YUQING - Mississippi State University; CHANG, SAM - Mississippi State University; LI, JIAXU - Mississippi State University; Maleki, Soheila; PUPPALA, NAVEEN - New Mexico State University

Submitted to: Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2019
Publication Date: 7/16/2019
Citation: Shi, M., Tan, Y., Chang, S., Li, J., Maleki, S.J., Puppala, N. 2019. Peanut allergen reduction and functional property improvement by means of enzymatic hydrolysis and transglutaminase crosslinking. Food Chemistry. https://doi.org/10.1016/j.foodchem.2019.125186.
DOI: https://doi.org/10.1016/j.foodchem.2019.125186

Interpretive Summary: Before this study, no studies have been conducted on peanut hydrolysates that are crosslinked with enzymes. Testing allergenicity and functional properties of peanut protein hydrolysate cross-linked by TGase (a type of peptide crosslinking enzyme) would increase scientific understanding of the usefulness of this cross-linking process. In this study, studies were conducted to: 1) select efficient food grade-enzymes for hydrolyzing peanut protein to further reduce allergen potency in roasted peanut powders; 2) test functional properties (emulsifying, foaming capacity and stability) after hydrolysis; and 3) test TGase for processing as a suitable treatment to further reduce allergenicity and to improve functional properties of peanut hydrolysates. The results from our experiments showed that hydrolysis of proteins into peptides may reduce allergenicity. TGase induced-crosslinking improved the functional properties of the peanut protein hydrolysates, but the cross-linked products maintained similar immuno-binding properties.

Technical Abstract: Enzymatic processing could reduce the allergenicity of peanut proteins while may lose the functional properties. Transglutaminase (TGase) is an enzyme for improving the functional properties of proteins/hydrolysates. No studies have been conducted on peanut hydrolysates that are crosslinked with TGase. In this study, allergenicity and functional properties of peanut protein hydrolysate cross-linked by TGase were tested. Papain, ficin and bromelain were selected out of eight food-grade enzymes for the kinetic analysis of peanut protein hydrolysis that lead to high reduction rate (K) of the IgE-binding property. Peanuts hydrolyzed by the three selected enzymes (200 AzU/g) were used for IgE binding, TGase-crosslinking and functional property characterization. After hydrolysis, the IgE-binding properties of the peanut soluble extracts were decreased (by 85%–95%); and functional properties were also decreased as compared to intact peanut protein extracts. The TGase crosslinked hydrolysates had similar IgE-binding properties to the un-crosslinked hydrolysates, but with higher functional properties.