Paper Partition Chromatography of the Free Amino Acids in American Cheddar Cheese

Although early investigators have analyzed cheddar cheese for some of its protein decomposition products by standard chemical methods, it was not until recently that a more systematic study of the free amino acids in cheese was attempted.VanSlyke and Hart (11) were among the first to investigate the nitrogenous compounds of American cheddar cheese.They were able to show the presence of tyrosine, histidine, lysine and traces of arginine and tyramine.In another investigation, Tuckey et al. (10) working with X-ray diffraction patterns, extracted and identified leucine, isoleucine, tyrosine and probably tryptophane from ripened cheddar cheese.In recent years, Harper and Swanson (7) using a microbiological method, have shown the presence of nine free amino acids in cheese.These were leucine, isoleucine, valine, glycine, proline, glutamic acid, aspartic acid, phenylalanine and lysine.Also, by means of microbiological assay, Reihard and Garey (9) showed the presence of a number of amino acids in both green and ripened cheese.Although definite progress has been made in this field, further research is necessary to attain a more complete picture of the free amino acids and amines in cheese and to evaluate their role in cheddar cheese ripening.Paper partition chromatography was applied by the author to the determination of free amino acids and amines in ripened cheddar cheese with the hope that it might be possible to show the existence of more free amino acids and also hitherto unsuspected compounds.