Amines in Cheddar Cheese

Amines and related compounds probably play an important part in flavor development in Cheddar cheese.These in turn are related to the bacterial enzyme systems present.In this study the presence of a number of amines in ripening cheese was determined and their relation to cheese flavor was studied by chromatographic methods.Editor.Among the more interesting compounds in Cheddar cheese, the amines as a group have received relatively little attention with respect to cheese ripening.Recent studies (1, 9, 10) have dealt either with a few cheeses or with a few of the compounds.In a reappraisal of colored areas on two-dimensional amino acid chromatograms of some Cheddar cheese, Silverman (13) expressed the belief that one of the large areas, hitherto unidentifiable, consisted of two or three amines of the type usually associated with unpleasant flavors or odors.As several lots of experimental Cheddar cheese designed initially by the authors for other research purposes had developed strong unclean flavors and in view of the availability of a refined method for amines on a large scale, an excellent opportunity was presented to study more fully the nature of aromatic amines in cheese.Later the investigation was extended to commercial Cheddar cheese. METHODS Cheese samples.A series of raw and pasteurized milk Cheddar cheeses from the same milk supply was made according to the directions of Lochry et al. (11) and ripened under vacuum in tin cans at 60 ° F. for 6 months.Observations were made periodically for flavor, soluble protein, amines, and related compounds.Twenty-three samples of mature commercial Cheddar cheese, 11 from raw milk and 12 from pasteurized milk, were analyzed in the same manner. Amine extraction and resolution a~zalysis.Ten g. of cheese was ground to a paste in a mortar with 10 ml. of 20°-25 ° C. water.The slurry was filtered through Whatman No. 12 paper into a test tube and washed with another 10 ml. of water.The cheese filtrate was placed in a boiling water bath for 10 minutes and then cooled to room temperature.To a 15-ml.aliquot of this filtrate 1.5 ml. of 50% trichloroacetic acid was added.This mixture was well agitated and after 5-8 minutes was filtered through Whatman No. 42 paper.