Functionality and Application of Rice Bran Protein Hydrolysates in Oil in Water Emulsions: Their Stabilities to Environmental Stresses
Rice bran protein hydrolysates (RBPH) were prepared from defatted rice bran of two different Thai rice cultivars (Plai-Ngahm-Prachinburi; PNP and Khao Dok Mali 105; KDM105) using an enzymatic method. This research aimed to optimize enzyme-assisted protein extraction. In addition, the functional properties of RBPH and their stabilities to environmental stresses including pH (3 to 8), ionic strength (0 mM to 500 mM) and the thermal treatment (30 °C to 90 °C) were investigated. Results showed that enzymatic process for protein extraction of defatted rice bran was as follows: enzyme concentration 0.075 g/ 5 g of protein, extraction temperature 50 °C and extraction time 4 h. The obtained protein hydrolysate powders had a degree of hydrolysis (%) of 21.05% in PNP and 19.92% in KDM105. The solubility of protein hydrolysates at pH 4-6 was ranged from 27.28-38.57% and 27.60-43.00% in PNP and KDM105, respectively. In general, antioxidant activities indicated by total phenolic content, FRAP, ferrous ion-chelating (FIC), and 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) of KDM105 had higher than PNP. In terms of functional properties, the emulsifying activity index (EAI) was was 8.78 m²/g protein in KDM105, whereas PNP was 5.05 m²/g protein. The foaming capacity at 5 minutes (%) was 47.33 and 52.98 in PNP and KDM105, respectively. Glutamine, Alanine, Valine, and Leucine are the major amino acid in protein hydrolysates where the total amino acid of KDM105 gave higher than PNP. Furthermore, we investigated environmental stresses on the stability of 5% oil in water emulsion (5% oil, 10 mM citrate buffer) stabilized by RBPH (3.5%). The droplet diameter of emulsion stabilized by KDM105 was smaller (d < 250 nm) than produced by PNP. For environmental stresses, RBPH stabilized emulsions were stable at pH around 3 and 5-6, at high salt (< 400 mM, pH 7) and at temperatures range between 30-50°C.
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 Elizabeth, P. R. “Bioactive food components and health properties of rice bran,” J AmVetMed Assoc, 238(5), 2011, pp. 593-600.
 Khalid G., Basharat, Y., Singh, A. K., Singh, P. and Wani A. A. “Rice bran: Nutritional values and its emerging potential for development of development of functional food-Review,” Bioact Carbohydr Dietary Fibre, 6, 2015, pp.24-30.
 Hanmoungjai, P., Pyle, D. L. and Niranjan, K. “Enzyme-assisted water-extraction of oil and protein from rice bran,” J ChemTechnol Biotechnol, 77, 2002, pp. 771-776.
 Saunders, R. M. “The properties of rice bran as a food stuff,” Cereal Food World 35, 1990, pp. 632-662.
 Fabian, C. and Ju, Y. “A Review on rice bran protein: Its properties and extraction methods, ”Cri Rev Food SciNutr, 51, 2011, pp. 816-827.
 Patsanguan, S., Hisaranusorn, N., Phongthai, S. and Rawdkuen, S. “Riec bran protein isolates: Preparation and their physico-chemical and functional properties,” Food App Biosci J, 2(3), 2015, pp. 169-182.
 Juliano, B. O. 1985. Rice: Chemistry and technology. 2nd ed., St. Paul, Minnesota: American Association of cereal chemists.
 Hamada, J. S. “Characterization of protein fractions of rice bran to devise effective methods of protein solubilization,” Cereal Chem, 74, 1997, pp. 662-668.
 Hamada, J. S. “Characterization and functional properties of rice bran proteins modified by commercialexoproteases and endoproteases,” JFood Sci, 62, 2000, pp. 305-310.
 Ansharullah, H. J. A. and Chesteman, C. F. “Application of carbohydrates in extracting protein from rice bran,” J Sci Food Agri, 4, 1997, pp.141-146.
 Pommer, K. “New proteolytic enzymes for the production of savory ingredients,” Cereal Food World, 40, 1995, pp.745-748.
 AOAC. Official Method of Analysis Vol.2. 17th ed., 2000, pp. 684. Association of Official Analytical Chemists: Washington, D. C.
 Matthew, P. M., Lauren, E. B., Rajesh, N. D., Beth, A. L., Mark, P. and Daniel, O. B. “Applying dry powder coating to pharmaceutical powders using a comill for improving powder flow and bulk density,” Powder Tech, 212, 2011, pp.397-402.
 Klompong, V., Benjakul, S., Kantachot, D. and Shahidi, F. “Antioxidative activity and functional properties of protein hydrolysate of yellow trevally (Selaroides leptolepis) as influenced by the degree of hydrolysis and enzyme type,” FoodChem, 102, 2009, pp. 1317-1327.
 Adler-Nissen J. “Determination of the degree of hydrolysis of food protein by trinitrobenzenesulfonic acid,” JAgrFood Chem, 27, 1979, pp. 1258-1262.
 Benjakul, S. and Morrissey, M. T. “Protein hydrolysates from pacific whiting solid wastes,” JAgrFood Chem, 45, 1997, pp. 3423-3430.
 Chan, E. W. C., Lim, Y. Y., Wong, S. K, Lim, K. K., Tan, S. P. and Lianto, F. S. “Effects of different drying methods on the antioxidant properties of leaves and tea of ginger species,”FoodChem, 113(1), 2009, pp. 166-172.
 Wang, Y., Zhang, M., Ruan, D., Shashkov A.S., Kilcoyne, M., Savage A.V., et al. “Chemical components and molecular mass of six polysaccharide isolated from the sclerotium of Poriacocos,” Carbohydr Res, 339, 2004, pp. 327-334.
 Floegel, A., Kim, Dae-Ok., Chung, Sang-Jin., Koo, Sung I and Chun, Ock K. “Comparison of ABTS/DPPH assays to measure antioxidant capacity in popular antioxidant-rich US foods,” JFood ComposAnal, 24, 2011, pp. 1043-1048.
 Adjimani, J. P. and Asare, P. “Antioxidant and free radical scavenging activity iron chelators,” Toxico Rep, 2, 2015, pp. 721-728.
 Bandyopadhyay, K., Charaboty, C. and Barman, A. K. “Effect of microwave and enzymatic treatment on the recovery of protein from Indian defatted rice bran meal.” J Oleo Sci, 61, 2012, pp. 525-529.
 Pearce, K. N. and Kinsella, J. E. “Emulsifying properties of protein: evaluation of a turbidimentric technique,” JAgrFood Chem, 26, 1978, pp. 716-723.
 Sari, Y. W., Bruins, M. E. and Sanders, J. P. M. “Enzyme assisted protein extraction fromrapeseed, soybean and microalgae meals,” Ind Crops Prod, 43(9),2012, pp. 78– 83.
 Khan, S. H., Butt, M. S., Sharif, M. K., Semeen, A., Mumtaz, S. and Sultan, M. T. “Functional properties of protein isolates extracted from stabilized rice bran by microwave, dry heat and parboiling,” JAgrFood Chem, 59, 2011, pp. 2416-2420.
 Mao, X. and Hua, Y. “Composition, structure and functional properties of protein concentrates and isolates produced from walnut (Juglans regia L.),” Int J Mol Sci, 13, 2012, pp. 1561-1581.
 He, R., Abaham, T. G., Malomo, S. A., Ju, X. and Aluko, R. E. “Antioxidant activities of enzymatic rapeseed protein hydrolysate and the Membrane ultrafiltration fraction,” JFunctFood, 5, 2013, pp. 219-227.
 Kaewumporn, T. “Effects of pH and coagulant of functional properties of mung bean protein products,” Bangkok, Thailand: Kasetsart University, MSc thesis, 2006, pp. 67-72.
 Chobert, J. M., Bertrand-Harb, C. and Nicolas, M. G. “Solubility and emulsifying properties of caseins and whey proteins modified enzymatically by trypsin,” JAgrFood Chem, 36, 1988, pp. 883-886.
 Kinsella, J. E. “Functional properties of food proteins in foods: a survey,” CritRev Food SciNutri, 8(4),1976, pp. 219-280.
 McClements, D. J. Food Emulsions: principles, practice, and techniques. New York: CRC Press LLC.1999.
 Chabanon, G. and Chevalot, L. “Hydrolysis of rapeseed protein isolates: Kinetics, characterization and functional properties of hydrolysates,” Process Biochem, 42, 2007, pp. 1419-1428.
 Phillips, R. D. and Beuchat, L. R. “Enzyme modification of proteins,”. In Cherry, J. P. (Ed). Protein functionality in foods, Washington, D.C.: American Chemical Society.1981, pp. 275.
 Damodaran, S. “Function properties,” In Nakai, S. and Modler, H. W. (Eds). Food proteins properties and characterization, New York: Wiley.1996, pp. 167-234.
 Tang, S., Hettiararchy, N. S., Eswaranandam, S. and Chandall, P. “Protein extraction from heat-stabilized defatted rice bran. 2. The role of amylase celluclast, and viscozyme,”JFood Sci, 68, 2003, pp.471-475.