Concentration of volatile components in foods with porous polymer column

A concentration method of volatile compounds onto a small column packed with porous polymer beads was proposed for foods, especially liquor. One liter of various flavor solutions were passed through the column packed with 5 ml of porous polymer beads (50~80 mesh) and the adsorbed volatile compounds were eluted with 20 ml of ethyl ether. 1) Among six kinds of beads, Porapak Q and Chromosorb 106 gave the best recoveries of volatile compounds from the 20% ethanol solution. 2) Alcohols, aldehydes and esters with carbon atoms more than 6 were recovered quantitatively from the ethanol-free solution. 3) In 20% ethanol sloution, the recoveries of hexanol, hexanal and ethylbutyrate decreased to 63, 86, 89%, respectively but the compounds with carbon atoms more than 8 were recovered completely. 4) When the solution contained ethanol 30% or above, the recoveries were greatly decreased. Therefore, a dilution with water and/or salting out technique were required prior to the treatment. 5) The recoveries were little affected by addition of surface-active agents. 6) When the volatile compounds were extracted from the column with ethyl ether of four-fold volume of resin, the recoveries were above 97% for all compounds. The residuals were completely extracted by an additional extract. The concentrations of volatile compounds from a commercial beer were done in order to compare the present method with a simultaneous distillationextraction (SDE) method under reduced pressure. As a results, the present method gave excellent recoveries in not only high boiling compounds but also acidic and phenolic, and basic compounds. The mean reproducibility (n=5) of arbitrarily selected 12 peaks was 14.0% for the present method and 37.9% for SDE method as a relative standard deviation.