Farah Nadiah Abd Rahim , Wan Zunairah Wan Ibadullah , Nazamid Saari , Nor Afizah Mustapha , Fatema Hossain Brishti , Ismail-Fitry Mohammad Rashedi , Radhiah Shukri
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引用次数: 0
Abstract
Changes in protein concentration (PC), pH, and ionic strength (IS) influenced the physicochemical, structural, and rheological properties of emulsions made with natural emulsifiers. This study used rice bran protein concentrates (RBPC) to create RBPC-stabilized emulsions (RBP-E) and examined their emulsifying function by changing protein concentration, ionic strength, and pH. The results showed that increasing the PC resulted in a decrease in particle size, which caused the creaming rate and viscosity of RBP-E to increase, leading to the depletion flocculation phenomenon. Incorporating PC into the emulsion system improved adsorbed protein performance in particular pH, which positively correlates to the reduction of emulsion capacity in 3 % PC at neutral conditions. The introduction of IS decreased viscosity, enhanced solubility, and increased protein adsorption, thereby improving emulsion stability within a 3 % protein concentration. FTIR analysis revealed that as the pH shifted from 3 to 7, the α-helical structures increased, while β-sheet and β-turn structures reduced compared to untreated protein, decreasing surface hydrophobicity. Incorporating 1 % PC improved RBP-E performance at pH 7 and 0.5 M, while 2 % PC optimized emulsion capacity at 0.25 M and pH 3. Increasing PC from 1 % to 2 % improved emulsion stability and capacity by 35.4 and 34.4 %, respectively, at 0 M, particularly at pH 5. Therefore, the study concludes that IS, pH, and PC affect the adsorption of plant-derived protein at the O/W interface and enhance the emulsification capabilities of RBPC and the stability of RBP-stabilized emulsions. RPB-E can potentially be used in cake batter, ice cream mix, and margarine premix, a sustainable substitute for animal-based proteins.
期刊介绍:
Official Journal of the European Federation of Chemical Engineering:
Part C
FBP aims to be the principal international journal for publication of high quality, original papers in the branches of engineering and science dedicated to the safe processing of biological products. It is the only journal to exploit the synergy between biotechnology, bioprocessing and food engineering.
Papers showing how research results can be used in engineering design, and accounts of experimental or theoretical research work bringing new perspectives to established principles, highlighting unsolved problems or indicating directions for future research, are particularly welcome. Contributions that deal with new developments in equipment or processes and that can be given quantitative expression are encouraged. The journal is especially interested in papers that extend the boundaries of food and bioproducts processing.
The journal has a strong emphasis on the interface between engineering and food or bioproducts. Papers that are not likely to be published are those:
• Primarily concerned with food formulation
• That use experimental design techniques to obtain response surfaces but gain little insight from them
• That are empirical and ignore established mechanistic models, e.g., empirical drying curves
• That are primarily concerned about sensory evaluation and colour
• Concern the extraction, encapsulation and/or antioxidant activity of a specific biological material without providing insight that could be applied to a similar but different material,
• Containing only chemical analyses of biological materials.