A novel preparation strategy of emulsion gel solely stabilized by alkaline assisted steam-cooking treated insoluble soybean fiber. (August 2022)

• Record Type: Journal Article
• Authors: Zhao, Xiujie; Chen, Bifen; Sun, Zhehao; Liu, Tongxun; Cai, Yongjian; Huang, Lihua; Deng, Xinlun; Zhao, Mouming; Zhao, Qiangzhong
• Is Part Of: Food hydrocolloids. Volume 129(2022)
• Publication Date: 2022-08
• Subjects: Insoluble soybean fiber (ISF) -- Steam-cooking -- Emulsion gel -- Microstructure -- Rheological property; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2022.107646
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: In this work, the insoluble soybean fiber, which was derived from okara facilely prepared by alkaline assisted steam-cooking treatments (AST-ISF), was used to prepare emulsion gels through regulating oil volume fraction ( φ, 0.1–0.6) and ISF concentration ( c, 0.05%–0.5%). AST-ISF was mainly composed of insoluble fiber (82.99 ± 0.24%), and most proteins were removed by alkaline treatment. AST endowed ISF with a higher crystallinity index (47.30 ± 0.82%) and moderate interfacial wettability (87.2 ± 1.2°), which facilitated the adsorption of AST-ISF at the oil-water interface and the formation of a stronger gel-like network structure. Raw okara and alkaline treated ISF could not form emulsion gels. In contrast, the emulsion gels could be formed by AST-ISF, and it was enhanced by AST-ISF adsorbing and entrapping with the oil phase. Oil volume fraction was a crucial factor affecting the microstructure. Especially when φ = 0.5, the degree of droplet aggregation was particularly prominent, and the elastic modulus increased up to about ten times compared with that at φ = 0.1. The minimum AST-ISF concentration to form emulsion gel was 0.3%. The study revealed that the structure of AST-ISF stabilized emulsion gel was characterized as a hybrid network structure composed of tightly packed oil droplets with cross-linked ISF in the continuous phase. Graphical abstract: Image 1 Highlights: Emulsifying property of insoluble soybean fiber (ISF) is improved by steam-cooking. ISF with proper crystallinity and θ wo facilitates formation of gel-like structure. Gel-like structure is composed of tightly packed droplets with cross-linked ISFs. Strength of emulsion gel is enhanced by ISF adsorbing and entrapping with droplets.