Effect of enzyme pre-treatment on extraction yield and quality of fennel (Foeniculum vulgare) volatile oil

The effect of enzyme pre-treatment on extraction yield and quality of volatile oil of fennel seeds were evaluated using various enzymes viz., Celluclast, Pectinex, Viscozyme and Protease. Scanning Electron Microscopic (SEM) studies were conducted to visualize the effect of these enzymes on fennel seed cell walls. The quality of the oil was further evaluated using Gas Chromatography Mass spectroscopy (GC-MS). The enzyme pre-treatment resulted in an increase in yield of oil in the range of 11-22.5% as compared to the control sample. Scanning electron microscopic studies revealed a marked difference between the structures of fennel seeds treated with enzymes than the non-treated seeds. GC-MS studies revealed that the flavor composition of the fennel oil remains unchanged even after pre-treatment. From an economic perspective, the results of the present study could be used effectively in the spice industry to increase the extraction yield of volatile oil from fennel seeds.