a study of the quality of a local herbal tea and volatiles of parinari ...

In Scheme 2.2 linolenic acid is transformed into the 13- or 9-hydroperoxy acid by
lipoxygenase. These intermediate products might be split into aldehydes and oxo acids by
an enzyme called aldehyde lyase (Tressl and Drawert, 1973).
2.4.4 Metabolism of carbohydrates (isoprenoid pathway)
Terpenes of fruit and vegetable aromas are a class of volatile compounds that constitute
the characteristic components of many essential oils, and contribute to, and in some cases
determine the aroma of many fruits (Sanz et al., 1997). There are two main types of
terpenoids that may contribute significantly to the flavour of vegetables and fruits, these
are monoterpenes and sesquiterpenes. Tissue disruption does not normally alter the
profile of monoterpenes and sesquiterpenes in the raw product, although changes in the
concentration of some monoterpenes may occur due to oxidation and release of
glycoside-bound oxygenated terpenoids (Berger, 2007).
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