title: Rennet-induced aggregation and curd formation from skimmed milk powders prepared under different sterilizing conditions.
abstract: Heat treatment during the production of skimmed milk powder causes denaturation of proteins, thereby affecting the physicochemical properties of the skimmed milk powder. To understand the effects of heat treatment on the sensitivity of the casein micelles in skimmed milk powders, low heating type (L), normal heating type (N), high heating type (H), and super-high heating type (SH), to reaction with rennet, rennet-induced curd formation was investigated. A well-developed network structure with wide spaces was observed only in the curd derived from the solution of type L skimmed milk powder. SDS-PAGE suggested that there was no difference in the amount of glycomacropeptide generated from kappa-casein in the four types of skimmed milk powder, but casein micelles in the solution of type L skimmed milk powder formed aggregates most effectively. These results are discussed with respect to the thermal denaturation of proteins in skimmed milk powder.
authors.affiliation: Laboratory of Quality Analysis and Assessment, Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan. yumiyamo@mukogawa-u.ac.jp
authors.forename: Yuka
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Kentaro
authors.initials: K
authors.lastname: Matsumiya
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kubouchi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Noda
authors.forename: Kimio
authors.initials: K
authors.lastname: Nishimura
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Matsumura
mesh_terms: D000818:Animals; D012085:Chymosin / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D008855:Microscopy, Electron, Scanning; D008892:Milk; D010316:Particle Size; D011489:Protein Denaturation; D013242:Sterilization
chemical_list: C025350:rennet; D012085:Chymosin