Influence of enzymatic pretreatment on yield and chemical composition of Rosmarinus officinalis essential oil

Effect of enzymatic pretreatment before hydrodistillation process on yield and composition of Rosmarinus officinalis essential oil was studied. Results obtained by using two selected commercial enzymes applied in food and beverage industry were compared. Control process with non-enzymatic pretreatment in analogous conditions was also performed for proper interpretation of results. Application of gas chromatography with mass selective detector (GC-MS) enabled analysis and comparison of essential oils composition. Moreover, total phenolic content (TPC) was determined spectrophotometrically in post-processing hydrolates, which are also valuable products e.g. for cosmetic applications. Modifications of isolation process by pretreatment with selected enzymes resulted in significant increase in essential oil yields in comparison to conventional hydrodistillation and control process with non-enzymatic pretreatment in analogous conditions. No substantial changes in the composition of obtained essential oils were observed. In post-processing hydrolates higher values of total phenolic content (TPC) were found both after enzymatic and non-enzymatic pretreatment.