Dados do Trabalho

Título

OPTIMIZATION OF ANTHOCYANINS EXTRACTION FROM GRAPE POMACE APPLYING FACTORIAL DESIGN

Introdução

Grape pomace is a co-product of the production of grape wines that contain phenolic compounds, such as anthocyanins, which have high antioxidant activity. Thus, grape pomace can be used to produce functional foods. Anthocyanins are potential pharmaceutical ingredients because they exhibit anticancer, antidiabetic, antimicrobial, cardiovascular disease prevention effects, among others. In order to obtain high anthocyanin values, an optimization of the extraction factors is necessary. Currently, multivariate optimization tools are being widely used for this purpose, as they can produce more realistic results when considering the interdependence of variables combined with saving bench time. Therefore, the main objective of this present work is the multivariate optimization of anthocyanin extraction parameters through factorial design. The variables studied were extraction time, temperature, extraction solvent and peel:solvent ratio.

Material e Métodos

A 24 factorial design was carried out, in which the following factors were evaluated at two levels: (1) extraction time: 60 min and 90 min; (2) temperature: 30 °C and 50 ºC; (3) extraction solvent: 0% and 50% ethanol; and (4) peel:solvent ratio: 10:100 and 30:100. For the quantification of anthocyanins, the single pH method was used, using ethyl alcohol acidified with 1.5 N HCl. Each experiment was repeated 3 times in a random manner to minimize errors. Significant effects were determined at a 90% confidence level.

Resultados e Discussão

It was observed that factor 3 at the upper level (50% ethanol), factor 2 at the upper level (temperature of 50 ºC) and the combination of these factors were significant, showing higher anthocyanin values. Effects 1 and 4 proved to be inert as it and its combinations were not significant. Multivariate optimization proved to be an effective tool for defining the best conditions for extracting anthocyanins, observing values of 335.9 mg/100 g.

Conclusão

By evaluating the interactions of factors, extraction can be optimized to obtain higher anthocyanin values.