The Tyramine Content of Cheese

Abstract

A method for separating tyramine from tyrosine and for estimating the concn. of the former substance was applied to cheese. This method involved the use of a continuous ether extractor and the employment of the Millon reagent using a colorimeter. 25 samples of commercial American Cheddar cheese of different age and history were tested for tyramine. All were found to contain tyramine in varying degrees of concn. The average for these samples was 384 [gamma] per g. or 0.0384%; the highest concn. was 1199 [gamma] per g. or 0.1199%, and the lowest was 25 [gamma] per g., or 0.0025%. A large number of miscellaneous vars. of ripened types of commercial cheese were tested for tyramine. Again, all samples were found to contain tyramine in varying concns. The largest amt. was found in a Liederkranz cheese which had a concn. of 1683 [gamma] per g., or 0.1683%, while the smallest amt. was found in a Roquefort cheese with a concn. of 48 [gamma] per g., or 0.0048%. The analyses were not sufficiently extensive to establish differences due to cheese variety. Tyramine was isolated from a sample of Cheddar cheese by this method, purified, and identified as the dibenzoyl derivative.