Managing diet quality for Cheddar cheese manufacturing milk. 1. The influence of protein and energy supplements

• Published in: Journal of dairy research 1999-08, Vol.66 (3), p.341-355
• Main Authors: CHRISTIAN, MARY P., GRAINGER, CHRIS, SUTHERLAND, BRIAN J., MAYES, JEFFERY J., HANNAH, MURRAY C., KEFFORD, BRUCE
• Format: Article
• Language: English
• Subjects: alphaS1-casein; Animal productions; Animals; barley; Biological and medical sciences; Caseins - analysis; Cattle; Cheddar cheese; Cheese - microbiology; cheese milk; Citric Acid - analysis; cottonseed meal; dairy cows; Diet; dietary minerals; dietary protein; Dietary Proteins - administration & dosage; Energy Intake; Female; Food industries; Food Technology; Fundamental and applied biological sciences. Psychology; gamma-casein; hay; inorganic phosphorus; lactation stage; late lactation; lupins; magnesium; Milk - chemistry; Milk - microbiology; Milk and cheese industries. Ice creams; milk composition; milk yield; Minerals - analysis; oats; protein supplements; rapeseed meal; seasonal variation; silage; sodium; sunflower meal; Terrestrial animal productions; Vertebrates; water content; wheat; yields
• ISSN: 0022-0299; 1469-7629
• DOI: 10.1017/S0022029999003647

The effects of supplementing cows' diets with protein and energy on milk composition and the composition and yield of Cheddar cheese were investigated. This research addresses the problems of seasonal reduction in the capacity of cheese curds to expel moisture as observed in parts of south-eastern Australia. Milk was collected from cows offered a basal diet of silage and hay supplemented with different sources and levels of dietary protein and energy. The protein supplements were sunflower, canola, cottonseed meal and lupin, and the energy supplements were maize grain, oats, wheat and barley. This milk was used to manufacture Cheddar cheese on a pilot scale. Cheese moisture content was dependent on the source and level of dietary protein and energy. Milk from cows offered the lupin protein supplements and wheat energy supplements consistently produced cheese with a lower moisture content and moisture in fat-free matter. Milk from these supplemented diets had increased casein concentrations and higher proportions of αs2-casein than milk from the poor quality control diet. Cheese yield was directly related to the total casein concentration of milk, but was not influenced by differences in casein composition. Supplementing the cows' diets increased the inorganic P, Mg and Ca concentrations in milk. A low inorganic P concentration in milk from cows offered the control diet was caused by a low intake of dietary P. These findings showed that changes in the mineral and casein composition of milk, associated with diet, could influence the composition of Cheddar cheese.