Influence of drying methods on the quality of sage (Salvia officinalis), parsley (Petroselinum crispum) and nasturtium (Tropaeolum majus)

The aerial parts of sage (Salvia officmalis), parsley (Petroselinum crispum) and nasturtium (Tropaeolum majus) cultivated in Egypt were collected and dried by different drying methods. Air and oven drying at 40 C produced dried sage and parsley contain higher amounts of essential oils. Essential oil constituents of air and freeze dried parsley samples were almost similar in comparison with fresh ones. Oven drying at 90 C adversely influences on essential oil quality resulting in a significant increase in some components. Air drying, oven drying (40 C) and freeze drying do not have significant effect on the chemical constituents of sage oil. By contrast, chemical constituents of sage essential oil are strongly affected by solar drying and oven drying (90 C) where it caused greater changes, in aroma. Drying methods had no significant effect on the content of flavones in parsley while freeze drying and oven-drying at 40 degrees C exhibited the highest nnaonylapiin / apiin ratios. In nasturtium, Freeze-dried samples contained the highest levels of glucotropaeolin. The glucotropaeolin concentrations decline to about and 70% of the original amount by using air and oven drying at 40 degrees C respectively.