Riboflavin-loaded soy protein isolate cold gel treated with combination of high intensity ultrasound and high hydrostatic pressure: Gel structure, physicochemical properties and gastrointestinal digestion fate

• Published in: Ultrasonics sonochemistry 2024-03, Vol.104, p.106819-106819, Article 106819
• Main Authors: Mao, Yuxuan, Li, Xinqi, Qi, Qi, Wang, Fang, Zhang, Hao, Wu, Yuzhu, Liu, Jingsheng, Zhao, Chengbin, Xu, Xiuying
• Format: Article
• Language: English
• Subjects: High hydrostatic pressure; High intensity ultrasound; In vitro digestion; Original; Riboflavin-loaded gel; Soy protein isolate
• ISSN: 1350-4177; 1873-2828
• DOI: 10.1016/j.ultsonch.2024.106819

[Display omitted] •Riboflavin was encapsulated in HIU-HHP combined treated SPI cold gel.•HIU-HHP combination enhanced mechanical property and structural stability of gel.•Stronger gel network improved encapsulation and chemical stability of riboflavin.•HIU and HHP synergistically promoted controlled release of riboflavin by gel.•Protein structure change during digestion led to higher riboflavin bioaccessibility. Transglutaminase (TGase) was added to soy protein isolate (SPI) dispersion after the combination treatment of high intensity ultrasound (HIU) and high hydrostatic pressure (HHP) to catalyze the formation of cold gel, which was used to encapsulate riboflavin. The structure, physicochemical properties and in vitro digestion characteristics of riboflavin-loaded SPI cold gel were investigated. HIU-HHP combined treatment enhanced the strength, water retention, elastic property, thermal stability and protein denaturation degree of riboflavin-loaded SPI cold gels, and improved the gel network structure, resulting in a higher encapsulation efficiency of riboflavin and its chemical stability under heat and light treatment. HIU-HHP combined treatment reduced the erosion and swelling of SPI cold gel in simulated gastrointestinal fluid, and improved the sustained release effect of SPI gel on riboflavin by changing the digestion mode and rate of gel. In addition, HIU-HHP combined treated gels promoted the directional release of riboflavin in the simulated intestinal fluid, thereby improving its bioaccessibility, which was related to the secondary structure orderliness, tertiary conformation tightness and aggregation degree of protein during the gastrointestinal digestion. Therefore, HIU-HHP combined treatment technology had potential application value in improving the protection, sustained/controlled release and delivery of SPI cold gels for sensitive bioactive compounds.