title: Effect of casein to whey protein ratios on the protein interactions and coagulation properties of low-fat yogurt.
abstract: In this study, we investigated the effect of casein (CN) to whey protein (WP) ratios (4:1, 3:1, 2:1, and 1:1) on gelation properties and microstructure of low-fat yogurt made with reconstituted skim milk with or without addition of whey protein concentrate. The rheological properties (storage modulus, G'; yield stress; and yield strain) of the obtained low-fat yogurt were greatly enhanced, the fermentation period was shortened, and the microstructure became more compact with smaller pores as the CN:WP ratio decreased. When CN:WP was 2:1 or 1:1, the obtained yogurt coagulum showed higher G' and greater yield stress, with more compact crosslinking and smaller pores. In addition, the more of skim milk powder was replaced by whey protein concentrate, the more disulfide bonds were formed and the greater the occurrence of hydrophobic interactions during heat treatment, which can improve the rheological properties and microstructure of low-fat yogurt.
authors: Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
authors: L L
authors: LL
authors: Zhao
authors: Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
authors: X L
authors: XL
authors: Wang
authors: Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
authors: Q
authors: Q
authors: Tian
authors: Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China. Electronic address: maoxueying@cau.edu.cn.
authors: X Y
authors: XY
authors: Mao
mesh_terms: D000818:Animals; D002364:Caseins; D006863:Hydrogen-Ion Concentration; D008892:Milk / Q000737:chemistry; D008894:Milk Proteins; D012212:Rheology; D000067816:Whey Proteins; D015014:Yogurt
chemical_list: D002364:Caseins; D008894:Milk Proteins; D000067816:Whey Proteins
keywords: casein to whey protein ratio; low-fat yogurt; microstructure; rheological behavior