Microwave-assisted Extraction of Monoterpenols in Must Samples

Abstract

The microwave-assisted extraction of five terpenic compounds associated with the varietal aroma of Vitis vinifera was developed and optimized by means of three- and two-level factorial designs. Four variables (extractant solvent volume, extraction temperature, amount of sample and extraction time) were considered as factors in the optimization process. The results suggest that the solvent volume and the amount of sample to be extracted are statistically significant for the overall recovery of the studied species, although compromise conditions have to be established in order to avoid losses of the extracted compounds in the concentration steps needed when the solvent volume increases. The optimum conditions established were applied to the extraction of real grape must samples and compared with the results given by conventional alternative procedures.

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