Preparation and Functional Properties of Rice Bran Protein Isolate

• Published in: Journal of agricultural and food chemistry Vol. 47; no. 2; pp. 411 - 416
• Main Authors: Wang, M, Hettiarachchy, N. S, Qi, M, Burks, W, Siebenmorgen, T
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.02.1999
• Subjects: 6-Phytase - chemistry; amino acid content; amino acids; Amino Acids - analysis; Animal, plant, fungal and microbial proteins, edible seaweeds and food yeasts; Biological and medical sciences; Calorimetry, Differential Scanning; Chemical Phenomena; Chemistry, Physical; children; emulsifying properties; Emulsions; enzymatic methods; foaming; foaming properties; Food industries; Fundamental and applied biological sciences. Psychology; hydrophobicity; nitrogen solubility; O-glycoside hydrolases; Oryza - chemistry; phytase; Plant Proteins - chemistry; Plant Proteins - isolation & purification; properties; protein content; protein isolates; protein value; rice bran; Xylan Endo-1,3-beta-Xylosidase; xylanase; Xylosidases - chemistry; yields; Cereal bran; Enzymatic treatment; Enzyme; 3-Phytase; Emulsifying power; Nutritive value; Foaming power; Phosphoric monoester hydrolases; Esterases; Protein isolate; Rice by product; Vegetal waste; Upgrading; Glycosidases; Aminoacid; Preparation; Plant protein; Hydrolases; Technological properties; Chemical composition; Yield; O-Glycosidases; Physicochemical properties
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf9806964

Rice bran protein isolate (RBPI) containing approximately 92.0% protein was prepared from unstabilized and defatted rice bran using phytase and xylanase. The yield of RBPI increased from 34% to 74.6% through the use of the enzymatic treatment. Nitrogen solubilities of RBPI were 53, 8, 62, 78, 82, and 80% at pHs 2.0, 4.0, 6.0, 8.0, 10.0, and 12.0, respectively. Differential scanning calorimetry showed that RBPI had denaturation temperature of 83.4 °C with low endotherm (0.96 J/g of protein). RBPI had similar foaming properties in comparison to egg white. But emulsifying properties of RBPI were significantly lower than those of bovine serum albumin. The result of amino acid analysis showed that RBPI had a similar profile of essential amino acid requirements for 2−5-year-old children in comparison to that of casein and soy protein isolate. Keywords: Rice bran; protein isolate; phytase; xylanase; functional properties