Reduced Xanthohumol Recovery after Solid Phase Extraction of Dark Beers
In wort and beer the hop polyphenol xanthohumol (XN) is often determined after solid phase extraction (SPE). Recently researchers described substances in roasted malts that help to enrich XN in dark beers. The carrier effect that reduces losses during beer production may influence the SPE as well. We investigated the XN recovery in dark beer samples with and without SPE sample preparation. In SPE eluates the XN recovery significantly decreased with increasing XN content compared to directly injected samples. Experiments on XN recovery in SPE passes repeatedly treated by SPE showed that this is not due to an overload of the sorbent. The use of SPE prior to XN determination in samples containing roasted substances proved to be inefficient compared to direct injection.
BrewingScience - Monatsschrift für Brauwissenschaft, 62 (July/August 2009), pp. 95-99