STUDIES ON FLAVOR CHANGES DURING DRYING OF DILL (Anethum sowa Roxb.) LEAVES

Abstract

Indian dill (Anethum sowa Roxb.) is a popular herb widely used in culinarypreparations and is characterized by a persistent cineolic flavor. To study the flavor quality of the fresh and dried herb, it was subjected to through-flow, cross-flow, vacuum andfreeze drying procedures. The volatile oils obtained from the fresh and dried samples were examined by gas chromatography and gas chromatography -mass spectrometry and the changes in their flavor compositions determined. Seventeen compounds have been identifed in Indian dill leaf oil, of which P-cubebene is being reported for the first time. The proximate composition of the dried herb is also reported.

Influence of different stabilizing operations and storage time on the composition of essential oil of thyme (Thymus officinalis L.) and rosemary (Rosmarinus officinalis L.)

“…Some volatile compounds evaporate during air-drying, whereas others are partially retained (Jerkovic, Mastelic, & Milos, 2001), and some oxidation products appear during drying (Luning, Ebbenhorstseller, Derijk, & Rozen, 1995). The loss of volatile compounds is generally correlated to drying air temperature and time (Raghavan, Abraham, Shankaranarayana, & Koller, 1994;Venskutonis, Poll, & Larsen, 1996). The decrease in volatiles can be minimized when drying air temperature is 50 C or below (Park, Vohnikova, & Brod, 2002;Soysal & Oztekin, 2001).…”

Effects of foaming agents and foam density on drying characteristics and textural property of banana foams

“…High drying temperature and long drying time have been noted to lead to losses of volatile compounds (Luning, Yuksel, Vuurst de Vries, & Roozen, 1995;Raghavan, Abraham, Shankaranarayana, & Koller, 1994). One of the effective methods to reduce volatile losses is shortening of the drying time.…”

Changes produced in the aroma compounds and structural integrity of basil (Ocimum basilicum L) during drying

“…The changes in volatile product concentration during the drying process depend on factors such as the drying method, the biological characteristics of the plants and their volatile composition. For example, oven drying and freeze‐drying applied to dill, parsley and spearmint lead to significant volatile losses 9–12. On the other hand, the effect of oven drying on the volatile components of bay leaf is much less, similar to that produced during air drying at ambient temperature, although important losses are also observed during freeze‐drying 13.…”

“…Not only have volatile losses and changes in the appearance of the plants been observed during the drying process, the concentration of some compounds also increases, eg eugenol in bay leaf,13 thymol in thyme and oregano14, 18, 19 and some monoterpene and sesquiterpene hydrocarbons 1, 10, 17, 20…”