Effects of extraction factors on protein recovery yield and emulsion stability index of protein from defatted rice bran

Nguyễn Văn Gí; Vương Bảo Thy; Nguyễn Ngọc Quí; Trần Ngọc Điệp; Đặng Xuân Đào; Trần Hữu Thanh Huy; Bùi Thế Vinh

Issue: Số 17 - Tháng 6 - 2026 Hóa học - Công nghệ thực phẩm

Effects of extraction factors on protein recovery yield and emulsion stability index of protein from defatted rice bran

Published: July 20, 2026

Abstract

Defatted rice bran (DRB) is a nutritionally rich agricultural by-product containing significant protein and bioactive compounds but remains underutilized. This study investigates the effects of single factors on protein extraction from DRB, including solvent type (distilled water, 30%, 50%, and 70% ethanol), solid-to-solvent ratio (1:1 to 1:13, w/v), and pH (5.0 - 10.0), on protein recovery yield and emulsion stability index (ESI). The results show that distilled water provides the best extraction performance, with protein recovery and ESI values of 71.38% and 73.70, respectively. The optimal ratio (1:10) increases recovery to 75.74% and ESI to 75.39, while pH 9.0 yields the highest recovery (82.46%) and ESI of 75.20. These findings provide a scientific basis for optimizing protein extraction from DRB and support the development of high-quality plant-based protein ingredients from agricultural by-products in Vietnam

Keywords

defatted rice bran emulsion stability recovery yield protein extraction

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