Application of solid-phase extraction for determination of phenolic compounds in barrique wines

摘要

A fast, selective and sensitive chromatographic method has been developed for determination of gallic, protocatechuic, p-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric, benzoic, ferulic, sinapic, cinnamic, and ellagic acids and p-hydroxybenzaldehyde, vanillin, syringaldehyde, 2-furfural, 5-methylfurfural, and 5-methoxfurfural. The compounds from untreated wine samples were pre-concentrated and cleaned using solid-phase extraction on RP-105 polymeric sorbent. The cartridge was conditioned with methanol and water. Co-extracted ballast substances were rinsed from the sorbent with 0.1 mol L~(-1) hydrochloric acid-methanol, 1:4(v/v). Retained phenolic compounds were selectively eluted with diethyl ether. A linear mobile phase gradient containing 0.3 acetic acid and methanol was used for final baseline chromatographic separation on a Hypersil BDS C18 column. Limits of detection (LOD = 3s_(bl)) in the range 5.2 to 181.2 μg L~(-1), resolution (R) better than 1.7, and repeatability of 2.7-5.1 (RSD for real samples) were achieved. The method was applied for quantification of individual phenolic compounds in barrique wines.