| Summary: | Red wine contains polyphenols which are extracted during the winemaking process. However, winemaking is not an extraction; therefore, the resulting byproducts still have a substantial polyphenol content. The aim of this study was to compare two methods for the extraction of phenolic compounds: maceration and matrix solid-phase dispersion (MSPD). Grape pomace (<i>Vitis vinifera</i> var. Cabernet Sauvignon) from a winery in Querétaro, Mexico was used. The optimal conditions for both methods were identified. Phenolic compounds and antioxidant activity were the response variables. A central composite design was used (Minitab 17) for the extraction by maceration. The maceration time (1, 4, 12, 20, and 24 h) and the ratio of ethanol (50 to 80%) acidified with 1% HCl were the two factors studied. For the MSPD extraction, sea sand was used as a dispersant, and a 2<sup>2</sup> factorial design was employed for the evaluation, with the elution volume and the ratio of sample/dispersant being the two factors analyzed. The optimal extraction method was MSPD with 96 mL (acidified ethanol) as the elution volume and a 1:2 ratio of sample/dispersant. Using these conditions, 14.01 ± 0.19 mMol TEAC/100 g db (Trolox equivalent of antioxidant capacity) of grape pomace was obtained, whereas the total phenolic content was 2836.73 ± 41.90 mg GAE/100 g db. These values are greater than those obtained by maceration. These conditions are close to those predicted by the model (analysis of variance (ANOVA) with a level of significance of 5% (<i>p</i> < 0.05) and a Tukey comparison test for determining significant differences in the comparison of results).
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