Variations in coagulation properties of cheese milk from three Danish dairy breeds as determined by a new free oscillation rheometry-based method

• Published in: Dairy science & technology Vol. 91; no. 3; pp. 309 - 321
• Main Authors: Frederiksen, Pernille Dorthea, Hammershøj, Marianne, Bakman, Mette, Andersen, Per Nyegaard, Andersen, Jens Bech, Qvist, Karsten Bruun, Larsen, Lotte Bach
• Format: Journal Article
• Language: English
• Published: Paris Springer-Verlag 01.05.2011; EDP Sciences; EDP sciences/Springer
• Subjects: Agriculture; Biological and medical sciences; Chemistry; Chemistry and Materials Science; Food and Nutrition; Food engineering; Food industries; Food Science; Fundamental and applied biological sciences. Psychology; Life Sciences; Microbiology; Milk and cheese industries. Ice creams; Original Paper; Curd firming rate (CFR); Coagulum strength; 品种间变化; Breed variation; 凝乳酶凝乳时间 (RCT); 凝块强度; Milk coagulation; 乳的凝固; 凝块硬化速率(CFR); Rennet coagulation time (RCT); Curd; Rate; Coagulation; Dairy product; Variations; Cheese; Oscillation method; Properties; Rennet; Dairy industry; Strength; Milk
• ISSN: 1958-5586; 1958-5594
• DOI: 10.1007/s13594-011-0018-5

The paper describes a study on the variation of coagulation properties in individual cow’s milk measured by a novel free oscillation rheometry-based method. The work is part of a study on the occurrence and underlying causes of poorly and even non-coagulating (NC) milk in Denmark, and based on that, the paper reports on the frequency of non- and poorly coagulating milk in a herd of the three main Danish dairy breeds, Jersey, Danish red (RDM), and Danish Holstein-Friesian (SDM). The cows were milked by automatic milking. The rennet coagulation time, the coagulum firmness by storage modulus G′, and the curd firming rate of fresh skimmed milk were determined. More than 20% of the milk samples exhibited poor coagulation properties by the criteria set. Of these, the 17% resulted in a weak coagulum after addition of rennet, while another 3% were due to NC milk that did not aggregate to form a curd within the 40 min of measurement. Milk from Jersey cows exhibited superior coagulation properties when compared to milk from SDM and RDM cows. The dependence of curd firming rate on protein concentration was investigated, and found to depend on milk protein concentration to the power of three, emphasizing the importance of protein interactions, and not just the protein concentration itself. The paper gives a basis for the subsequent selection of NC milk samples with the aim to look in more detail for the underlying reasons for the phenomenon of NC milk.