Age Gelation in Direct Steam Infusion Ultra-High-Temperature Milk: Different Heat Treatments Produce Different Gels
Peipei Wu,
Mengyuan Guo,
Pengjie Wang,
Yi Wang,
Ke Fan,
Hui Zhou,
Wentao Qian,
Hongliang Li,
Menghui Wang,
Xiaojun Wei,
Fazheng Ren,
Jie Luo
Affiliations
Peipei Wu
College of Food Science and Technology, Hunan Agricultural University, Changsha 410114, China
Mengyuan Guo
Key Laboratory of Functional Dairy, Co-Constructed by Ministry of Education and Beijing Government, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
Pengjie Wang
Key Laboratory of Functional Dairy, Co-Constructed by Ministry of Education and Beijing Government, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
Yi Wang
College of Food Science and Engineering, Tianjin University of Science & Technology, Tianjin 300457, China
Ke Fan
College of Food Science and Technology, Hunan Agricultural University, Changsha 410114, China
Hui Zhou
College of Food Science and Technology, Hunan Agricultural University, Changsha 410114, China
Wentao Qian
Mengniu Hi-Tech Dairy Products (Beijing) Co., Ltd., Beijing 101100, China
Hongliang Li
Mengniu Hi-Tech Dairy Products (Beijing) Co., Ltd., Beijing 101100, China
Menghui Wang
Inner Mongolia Mengniu Dairy (Group) Co., Ltd., Hohhot 011500, China
Xiaojun Wei
Inner Mongolia Mengniu Dairy (Group) Co., Ltd., Hohhot 011500, China
Fazheng Ren
Key Laboratory of Functional Dairy, Co-Constructed by Ministry of Education and Beijing Government, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
Jie Luo
College of Food Science and Technology, Hunan Agricultural University, Changsha 410114, China
To investigate the gelation process of direct ultra-high-temperature (UHT) milk, a pilot-scale steam infusion heat treatment was used to process milk samples over a wide temperature of 142–157 °C for 0.116–6 s, followed by storage at 4 °C, 25 °C, and 37 °C. The results of the physicochemical properties of milk showed that the particle sizes and plasmin activities of all milk samples increased during storage at 25 °C, but age gelation only occurred in three treated samples, 147 °C/6 s, 142 °C/6 s, and 142 °C/3 s, which all had lower plasmin activities. Furthermore, the properties of formed gels were further compared and analyzed by the measures of structure and intermolecular interaction. The results showed that the gel formed in the 147 °C/6 s-treated milk with a higher C* value had a denser network structure and higher gel strength, while the 142 °C/6 s-treated milk had the highest porosity. Furthermore, disulfide bonds were the largest contributor to the gel structure, and there were significant differences in disulfide bonds, hydrophobic interaction forces, hydrogen bonds, and electrostatic force among the gels. Our results showed that the occurrence of gel was not related to the thermal load, and the different direct UHT treatments produced different age gels in the milk.
