Study On Embedding Of Essential Oils By Extrusion And Lipidosome Technology

Essential oil is a kind of natural spices which extracted from aromatic plants.But it belongs to a group of mixture that has unstable chemical properties.Essential oil is easy to volatilization and oxidation.On the other hand,the single liquid form also limits its scope of application.Experience has shown that embedding of essential oil can not only improve stability but also broaden the scope of use.The main chemical constituents of essential oils are terpenoids,including terpenes and their oxygenated derivatives,such as alcohols,aldehydes,ketones and hydroperoxides.The research objects are five common essential oils:Rosemary,orange,peppermint,lavender and lemongrass.They are also involved in the alkenes,alcohols and aldehydes.In addition,one compound essential oil that formulated by them is also included in the study area.The two embedding techniques are as follows:modified starch HI-CAP100 as wall material of extrusion technology and ceramide as wall material of liposome technology.Embedding rate,morphology,particle size,life expectancy,oil retention rate of change in different temperature storage conditions,and changes in the types of chemical composition of essential oils are regarded as the evaluation index of embedding effect.The main conclusions are as follows:By extrusion technology,hydration temperature of essential oil microcapsule embedding is the most remarkable factor,alcohol oil microcapsule embedding rate is slightly higher than that of the terpenes and aldehydes,compound essential oil microcapsule embedding rate is the lowest that nearly to 70%.The life expectancy of alcohol oilmicrocapsule(peppermint,Lavender)is significantly longer than that of terpenes(rosemary,orange)and aldehydes(lemongrass).The lower the natural storage temperature,the higher the retention rate of essential oil.Most of the samples showed more obvious flocculation,stratification phenomenon in 20 days.The types of chemical composition of essential oils are not significantly changed after embedding.The components of alcohol oil microcapsule(peppermint,Lavender)is missing least,but compound essential oil is missing most.Alcohol oil(peppermint,Lavender)microcapsule,s structure is complete and nearly to spherical.Its surface is smooth and performance is the most excellent.Compound essential oil microcapsule has not relative integrity of the structure.The lowest average particle size of microcapsules is rosemary essential oil which is 185.6±13.5nm,The highest is peppermint which is 243.5±9.4nm.The particle size distribution uniformity from high to low order are alcohols,terpenes and aldehydes.The average particle size of compound essential oil microcapsules is 228.9±11.7nm,and the multi dispersion coefficient is 0.096.By liposome technology,four process factors showed different effects on different types of essential oils.alcohol oil liposome embedding rate is slightly higher than that of the terpenes and aldehydes.The life expectancy of alcohol oil microcapsule(peppermint,Lavender)is significantly longer than that of terpenes(rosemary,orange)and aldehydes(lemongrass).The lower the natural storage temperature,the higher the retention rate of essential oils.Most of the samples appeared slight turbidity only in 30 days.The types of chemical composition of essential oils are not significantly changed after embedding.They have no obvious difference.But compound essential oil is missing most.Terpene oil liposome,s surface has obvious concave.But alcohols and aldehydes oil liposome,s surface is smooth and close to spherical shape.Compound essential oil liposome have showed spherical shape clearly,densely and intensively.The lowest average particle size of liposome is lemongrass essential oil which is 116.9±4.6nm,The highest is Lavender which is 174.5±12.8nm..The particle size distribution uniformity from high to low order were alcohols,aldehydes and terpenes.The average particle size of compound essential oil liposomes is 161.3±13.5nm,and the multi-dispersion coefficient is 0.077.This study provides an objective basis for further study of the essential oil embedding technology application.Whether by extrusion or liposome technology,the embedding of essential oil can stabilize the composition.But different essential oils have different conditions.It is necessary to consider their chemical properties and application characteristics when select embedding technology.