Use of air classification technology to produce protein-enriched barley ingredients. (April 2018)

• Record Type: Journal Article
• Authors: Silventoinen, Pia; Sipponen, Mika Henrikki; Holopainen-Mantila, Ulla; Poutanen, Kaisa; Sozer, Nesli
• Is Part Of: Journal of food engineering. Volume 222(2018)
• Page Start: 169
• Page End: 177
• Publication Date: 2018-04
• Subjects: Barley -- Air classification -- Flow aid -- Protein -- Functional properties; DSC differential scanning calorimetry -- PSE protein separation efficiency -- RVA Rapid Visco Analyser; Food industry and trade -- Periodicals; Food -- Analysis -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Analyse -- Périodiques; Aliments -- Recherche -- Périodiques; 664.005
• DOI: 10.1016/j.jfoodeng.2017.11.016
• Languages: English
• ISSNs: 0260-8774

Abstract

Abstract: Air classification of an industrial barley endosperm fraction with initial protein content of 8.3% mixed with Aerosil 200F flow aid resulted in protein enrichment up to 28.3% with 21.7% protein separation efficiency. By reducing the classifier wheel speed from 21500 rpm to 8000 rpm, the protein separation efficiency increased to 59.4%, whereas the protein content only decreased to 22.3%. Microstructural analysis showed that small starch granules separated together with protein in the fine fraction and had more continuous protein matrix around them. The protein-enriched fraction obtained at 8000 rpm classifier wheel speed had limited protein solubility of 9.3% at native pH 5.1. Solubility increased in acidic (pH 3, 19.6%) and especially in alkaline (pH 11, 91.9%) conditions. Protein fraction had water and oil binding capacities of 1.2 and 1.1 g/g, respectively. Foaming properties tested at different pH-values revealed best capacity at pH 3. Thermograms showed two melting temperatures, varying from 60.0 to 64.2 °C and from 90.5 to 95.5 °C for all the studied fractions. Cereal side-streams such as the industrial barley endosperm fraction can be utilised as potential plant protein ingredient for various food/feed applications. However, further studies are needed to evaluate the technological, nutritional, and sensory characteristics of this protein enriched fraction. Highlights: Use of Aerosil flow aid enhanced barley protein separation in air classification. Protein enrichment up to 28.3% was achieved with 21.7% PSE. Alternatively, PSE of 59.4% was obtained with protein content of 22.3%. Protein formed aggregates containing small starch granules embedded.