EXAMINATION OF FULL-FAT AND REDUCED FAT CHEDDAR CHEESE DURING RIPENING BY FOURIER-TRANSFORM INFRARED-SPECTROSCOPY

The Fourier transform infrared spectra of reduced fat Cheddar cheese a nd full fat Cheddar cheese during ripening were examined. A suitable s ampling procedure was used to obtain the spectra of cheese samples. Th e spectra were affected by the moisture contents of the samples, but t his effect could be eliminated by equilibration of the sample for at l east 10 min before data collection. Strong and well-separated bands at 1744, 1450, 1240, 1170, and 1115 cm(-1) arising from fat were observe d in the frozen samples. The bands observed at 1650 and 1540 cm(-1) we re attributed to the protein contents of the cheese samples. The absor ption intensities of protein and fat bands corresponded to the amounts of protein and fat that were present in the samples. Distinct changes in the bands of fat and protein of reduced fat and full fat cheese sa mples occurred during ripening. This technique could provide a basis f or a rapid characterization and determination of the age of cheese und ergoing ripening.