[Development of volatile compounds from radicals arising during intermediate steps of the lipoxygenase-reaction (author's transl)].

The development of volatile compounds arising from radicals during intermediate reaction steps of the lipoxygenase-linoleic-acid-reaction (from soy) was investigated in model experiments with defined conditions. The results indicate as follows: Among the volatile compounds formed, hexanal has a special position. Its development is closely connected to the enzymatic formation of the 13-linoleic-acid-hydroperoxide because it is formed from the 13-linoleic-acid-peroxy-radical, which is a direct precursor of the 13-linoleic-acid-hydroperoxide. The other volatile products are apparently formed in the same way as by autoxidation. Their development is favoured by lack of oxygen, when the primarily formed linoleic-acid-radicals cannot react rapidly with the oxygen-radicals to form hydroperoxides. A small part of the volatile compounds is formed by autoxidation which always accompanies the enzymatic reaction.