EXTRACTION OF ESSENTIAL OILS FROM SPICES USING THE MICROWAVE TECHNIQUE FOR THE MANUFACTURE OF BIOFUNGICIDES.

摘要

The present invention consists in the development of the microwave technique for extracting essential oils from spices, using the classic methods of steam stripping, hydro distillation and extraction with solvents, adding a fourth method that is the direct distillation by microwaves, a comparative study being carried out between the different extraction techniques in the different studied spices, in this case cinnamon, clover, ginger and pepper. According to the analyzed extraction methods it is assumed that the best extraction method of cinnamon essential oil is by means of solvents (hexane), assisted with microwaves with a frequency of 2,450 MHz and a power of 0.2 Kw, using a total extraction time of 6450 seconds. For extracting the clover essential oil, the best extraction method is steam stripping, with a power in the microwave oven of 0.66Kw and a frequency of 2450 MHz, in a period of time of 6250 seconds. For extracting the ginger essential oil, the best extraction method is by means of direct distillation with microwaves, with a power of 0.3 Kw and a frequency of 2450 MHz, in a period of time of 7250 seconds. For extracting the pepper essential oil, the best extraction method is the hydro distillation method assisted by microwaves, with a power of 0.66 Kw and a frequency of 2450 MHz, in a period of time of 6660 seconds. The application of the microwave techniques results in extraction yields higher than those reported in the literature of each one of the analyzed spices. The analysis performed to the essential oils by RAMAN spectroscopy ensures that the use of the oils for producing biofungicidal will be assertive, since their composition includes terpenes, monoterpenes and phenols with biofungicidal properties widely reported in the literature.