title: Removal of milk fat globules from whey protein concentrate 34% to prepare clear and heat-stable protein dispersions.
abstract: Whey protein concentrates (WPC) are low-cost protein ingredients, but their application in transparent ready-to-drink beverages is limited due to turbidity caused by fat globules and heat instability. In this work, fat globules were removed from WPC 34% (WPC-34) to prepare heat-stable ingredients via the Maillard reaction. The removal of fat globules by acid precipitation and centrifugation was observed to be the most complete at pH 4.0, and the loss of protein was caused by micrometer-sized fat globules and protein aggregates. Spray-dried powder prepared from the transparent supernatant was glycated at 130°C for 20 and 30min or 60°C for 24 and 48h. The 2 groups of samples had comparable heat stability and degree of glycation, evaluated by free amino content and analytical ultracentrifugation, but high-temperature, short-time treatment reduced the color formation during glycation. Therefore, WPC-34 can be processed for application in transparent beverages.
authors.affiliation: Department of Food Science and Technology, The University of Tennessee, Knoxville 37996.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.affiliation: Department of Food Science and Technology, The University of Tennessee, Knoxville 37996. Electronic address: qzhong@utk.edu.
authors.forename: Qixin
authors.initials: Q
authors.lastname: Zhong
mesh_terms: D000818:Animals; D002498:Centrifugation / Q000662:veterinary; D005511:Food Handling / Q000379:methods*; D006017:Glycolipids / Q000302:isolation & purification*; D006023:Glycoproteins / Q000302:isolation & purification*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D066292:Lipid Droplets; D008894:Milk Proteins / Q000737:chemistry*; D000067816:Whey Proteins
chemical_list: D006017:Glycolipids; D006023:Glycoproteins; D008894:Milk Proteins; D000067816:Whey Proteins; C110367:milk fat globule
keywords: acid precipitation; glycation for heat stability; milk fat globule; whey protein concentrate 34%