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Donald McMahon

I teach dairy processing and technology and cheese science. My research focus is on the study milk proteins and their application in dairy foods. Along with a group of cheese experts from other universities, I co-lead the DMI Expert Cheese Group that through national cooperation between all five Dairy Foods Research Centers is providing a focus on cheese innovations.

Research Interests

Study of proteins in milk and how processing influences their structure and function. Present research includes the colloidal structure of casein micelles, changes that occur in milk proteins during cheese manufacture, and the role of milk proteins in the functional properties of cheese.

Electron microscopy can be used to study the structure of foods. At very high magnification, such as this image of a casein micelle magnified 200,000x, the arrangement of proteins can be studied. Milk contains 1015 casein micelles per milliliter. Each casein micelle is an aggregate of about 10,000 protein molecules that serves as a calcium phosphate transport supramolecule

Knowing how the components of a food interact provides a basis for controlling performance and designing food functionality. During cooling and the initial stages of mozzarella cheese ripening, free moisture is adsorbed into the protein matrix causing it to swell and completely surround the fat globules.