Molecular structures of high- and low-methoxy water-soluble polysaccharides derived from peas and their functions for stabilizing milk proteins under acidic conditions. (March 2023)

• Record Type: Journal Article
• Authors: Nakamura, Akihiro; Naeki, Rion; Kikuchi, Mayu; Corredig, Milena; Shima, Yugo; Fujii, Nanae
• Is Part Of: Food research international. Volume 165(2023)
• Publication Date: 2023-03
• Subjects: Pea -- Polysaccharides -- Methyl-esterification -- Protein -- Stabilization; Food -- Analysis -- Periodicals; Food industry and trade -- Periodicals; Food industry and trade -- Canada -- Periodicals; Food Technology -- Periodicals; Food -- Periodicals; Food-Processing Industry -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Industrie et commerce -- Canada -- Périodiques; Aliments -- Recherche -- Périodiques; Food industry and trade; Canada; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.foodres.2022.112390
• Languages: English
• ISSNs: 0963-9969

Abstract

Graphical abstract: Highlights: Pea soluble polysaccharides (SPPS) have an average mass of 1, 000 kg/mol. SPPS showed a straight chain/star-burst structure, with small side chains. The esterification degree affects their interaction with proteins under acidic conditions. SPPS stabilizes acidified milk protein particles by steric and electrostatic repulsion. Abstract: The structural and functional properties of two different pea water-soluble polysaccharides, a high methyl-esterified (HM-SPPS; degree of methyl esterification (DMe): 71.0 %) and low methyl-esterified SPPS (LM-SPPS; DMe: 25.2 %) were investigated. The two extracts did not vary in composition and showed a weight average molecular mass of about 1, 000 kDa, as measured by size exclusion chromatography equipped with a multi-angle light scattering detector. Both HM-SPPS and LM-SPPS had similar sugar compositions, with arabinose 42.2–47.1 %, glucose 26.6–31.0 %, and galacturonic acid 17.5–18.0 %, as their main sugars. Their charge varied as a function of pH. The molecular structure was observed by a scanning probe microscope and showed a straight chain structure with small branches. The structure was similar to that already reported for polysaccharides from kidney bean. SPPS molecules interact with acidified milk protein particles at pH < 4.4. There were differences between the two SPPS. LM-SPPS could stabilize a model acidified milk dispersion with minimal aggregation between pH 3.6–4.4, while HM-SPPS showed the presence of bridging flocculation caused by polysaccharide's entanglements. It was concluded that SPPS stabilizes acidified protein by steric and electrostatic repulsion