Amines, primary biochemical oxidation

Undoubtedly, the products of these primary biochemical events, i.e., fatty and other acids, peptides, and amino adds, contribute to cheese flavor, perhaps very significantly in many varieties and proteolysis certainly has a major influence on the various rheological properties of cheese, e.g., texture, meltability, and stretchability. However, the finer points of cheese flavor are almost certainly due to further modification of the products of the primary reactions. The most clear-cut example of this is the oxidation of fatty acids to methyl ketones in blue cheeses. Catabolism of amino acids leads to the production of numerous sapid compounds, including amines, carbonyls, acids, thiols, and alcohols. Many of these compounds may interact chemically with each other and the compounds of other reactions via the Maillard and Strecker reactions. At present, relatively little is known concerning the enzymology of amino acid catabolism in most cheeses and even less is known about the chemical reactions. It is very likely that research attention will focus on these secondary and tertiary reactions in the short-term future. 

Haywood, G. W., and Large, P. J., 1981, Microbial oxidation of amines dish ibution, purification and properties of two primary amine oxidases from die yeast Candida boidinii grown on amines as sole nitrogen source, Biochem. J. 199 187n201. 

The oxidative deamination of amines to ketones, via oxaziridines, was reported as a model for the process found in oxidative deamination of a-amino-acids to pyruvic acids in biochemical systems." The primary amine, such as (58) or (59) with pyridine-2-carboxaldehyde, was converted into the imine (60) which was oxidized with m-chloroperbenzoic acid to the oxaziridine (61). Ring opening of (61) was effected with KOH in MeOH or in DMF (Scheme 8). Acetone was added to trap regenerated pyridine-2-carboxaldehyde. When other bases were used a competing reaction resulting in (62) occurred. 

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