title: Acid-induced gelation behavior of soybean protein isolate with high intensity ultrasonic pre-treatments.
abstract: High intensity ultrasonic (HUS, 20 kHz, 400 W) pre-treatments of soybean protein isolate (SPI) improved the water holding capacity (WHC), gel strength and gel firmness (final elastic moduli) of glucono-δ-lactone induced SPI gels (GISG). Sonication time (0, 5, 20, and 40 min) had a significant effect on the above three properties. 20 min HUS-GISG had the highest WHC (95.53 ± 0.25%), gel strength (60.90 ± 2.87 g) and gel firmness (96340Pa), compared with other samples. Moreover, SH groups and non-covalent interactions of GISG also changed after HUS pre-treatments. The HUS GISG had denser and more uniform microstructures than the untreated GISG. Rheological investments showed that the cooling step (reduce the temperature from 95 to 25 °C at a speed of 2 °C/min) was more important for the HUS GISG network formation while the heat preservation step (keep temperature at 95 for 20 min) was more important for the untreated GISG. HUS reduced the particle size of SPI and Pearson correlation test showed that the particle size of SPI dispersions was negatively correlated with WHC, gel strength and gel firmness.
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China.
authors.forename: Hao
authors.initials: H
authors.lastname: Hu
authors.forename: Xin
authors.initials: X
authors.lastname: Fan
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhou
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Xu
authors.forename: Gang
authors.initials: G
authors.lastname: Fan
authors.forename: Lufeng
authors.initials: L
authors.lastname: Wang
authors.forename: Xingjian
authors.initials: X
authors.lastname: Huang
authors.forename: Siyi
authors.initials: S
authors.lastname: Pan
authors.forename: Le
authors.initials: L
authors.lastname: Zhu
mesh_terms: D055598:Chemical Phenomena; D005782:Gels; D005942:Gluconates / Q000737:chemistry; D007783:Lactones / Q000737:chemistry; D010316:Particle Size; D012212:Rheology; D012995:Solubility; D030262:Soybean Proteins / Q000737:chemistry* / Q000302:isolation & purification; D013438:Sulfhydryl Compounds / Q000737:chemistry; D014465:Ultrasonics / Q000379:methods*; D014867:Water / Q000737:chemistry
chemical_list: D005782:Gels; D005942:Gluconates; D007783:Lactones; D030262:Soybean Proteins; D013438:Sulfhydryl Compounds; D014867:Water; C010730:beta-glucono-1,5-lactone