engleski

HYDROLATES OF BAY LAUREL, ROSEMARY AND SAGE AS A SOURCE OF VOLATILE COMPOUNDS

The essential oil manufacture produces a significant quantity of co-products. These potentially valuable hydrodistillation residues include hydrolates contain a remarkable source of bioactive molecules. In this study, we have focused on aromatic Mediterranean plants rich in volatile compounds: bay laurel, rosemary and sage. Their essential oils are frequently used, but hydrodistillation residues produced in parallel with these essential oils are much less explored. Despite rich bioactive content, these fractions are often underexploited or even considered waste. Increasing market demand for essential oils resulted in the development of many innovative methods for improvement of their yield and composition. Traditional extraction technologies prior hydrodistillation mainly related to the high temperature mainted for long extraction periods and the consumption of hazardous organic solvents as well as low extraction efficiency of desired compounds. So, we have analysed different pretreatments prior to hydrodistillation i.e. reflux extraction, ultrasound and enzyme assisted extraction on chemical composition of hydrolates in bay laurel, rosemary and sage. GC-MS analysis showed that the hydrolates of all plants were richest in oxygenated monoterpenes: up to 46%, 42% and 30% of total peak area in bay laurel, rosemary and sage hydrolates, respectively. Sesquiterpenes were also well represented: up to 42%, and 10% of total peak area in rosemary and bay laurel hydrolates, respectively. Dominant compounds were confirmed: 1, 8-cineole, camphor, borneol and berbenone in rosemary hydrolates, 1, 8-cineole, linalool, camphor, α- and β-terpineol, methyleugenol and eugenol in bay laurel hydrolates and 1, 8-cineole, camphor, borneol and berbenone in sage hydrolates. In general, the pretreatments didn’t significantly affect the volatile compounds of hydrolates (p<0.05), i.e. the composition was comparable to the no-pretreatment control, as confirmed by Spearman´s test. Our results point out that hydrolates remaining after hydrodistillation of bay laurel, rosemary and sage are valuable source of oxygenated monoterpenes and sesquiterpenes and can find their application in many fields of food industry.

bay laurel, hydrodistillation, hydrolates, monoterpenes, rosemary, sage, sesquiterpenes

nije evidentirano