Composition and Microstructure of Commercial Full-Fat and Low-Fat Cheeses

The objective of this study was to analyze the composition of commercial full-fat and low-fat cheeses and to evaluate their microstructure. Commercial cheeses evaluated included full-fat and low-fat Cheddar, Mozzarella , processed, and Swiss cheeses. Cheddar cheeses ranged from 8.2% fat and 5 1.1% moisture in the 75% low-fat product to 33.2% fat and 35.9% moisture in the full-fat cheese . Mozzarella cheeses ranged in fat from a low of 2. I% to a high of 24% with corresponding moisture content of 56.6 to 45.5% respectively. Fatfree processed cheese had 0. 9% fat and 58.7% moisture , while the full - fat cheese had 32.3% fat and 37.4% moisture. Full -fat Swiss cheese had fat and moisture content of 34.8 and 36.7% , respectively. The corresponding values for the low-fat cheese were 27.6 and 40.1 %. Total protein con ten t of all cheeses increased with decreasing fat, but. the percent increase in protein was less than the percent reduction in fat. The ash content of Cheddar and Swiss also increased with a decrease in fat content. The fat con tent of cheeses affected the microstructure. Full -fat cheeses for all varieties were characterized by a protein matrix interspersed with fat globules of varying shape and size. Low-fat cheeses had fewer fat globules within the protein matrix, and the globules were usually smaller than in the full-fat cheese. The protein matrix dominated the structure of low-fat cheeses which would explain the firm, rubbery body and texture characteristics.