Food analysis carbonyl compounds

One area of application is the analysis of flavours in foods in order to ascertain, for example, the ripeness of fruit or the maturity of cheeses [42]. For this purpose dendrimers were used which can distinguish certain carbonyl compounds such as ketones, aldehydes, esters, and amides, also in mixtures. For example, measurement of the concentration of 2-heptanal is of importance specifically for determination of the degree of ripeness of apples. The concentration of this compound increases significantly with increasing ripeness [43]. This technique can also serve as an electronic nose for quality control of high-value products such as saffron, which in powder form may contain undesired contaminants (adulterants) such as curcuma, safflower, or marigold. 

Yasabura, A., Kawada, K. and Sbibamoto, T. gas Cbromatograpbic/mass spectrometric method for analysis of trace carbonyl compounds in foods and beverages. J. Agric. Food Chem. 46, 2664-2670 (1998). 

This chemical manipulation of the aqueous phase can be carried even further. Many food aromatics contain carbonyl compounds. By adding sodium bisulfite to the aqueous phase, it is possible to selectively remove the aldehydes and the methyl ketones by forming their water-soluble bisulfate addition complexes. Thus, this analysis produces a carbonyl-free sample. 

Spanier, A.M. and Drumm Boylston, T. 1994. Effect of temperature on the analysis of beef flavor volatiles Focus on carbonyl and sulfur-containing compounds. Food Chem. 50 251-259. 

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