Recent Developments in Imparting Hop Character to Beer. Derek R. J. Laws, Terence L. Peppard, F. Richard Sharpe and John A. Pickett, Brewing Research Foundation, Nutfield, Surrey, Great Britain RH1 4HY. J. Am. Soc. Brew. Chem. 36:0069, 1978.

Aqueous emulsions of hop oil, for use in imparting hop character to beer, can be conveniently prepared by the vacuum steam distillation of hops at ambient temperature. A rapid method, which involves steam distillation at atmospheric pressure, has been developed for estimating the concentration of hop oil in emulsions. When hops are treated by the new process a certain portion of the total oil appears to be bound. Hops used for preparing emulsions should be rich in oil and contain minimal levels of elemental sulphur. A number of sulphur-containing compounds, which have a deleterious effect on beer flavor, are formed by the reaction of elemental sulphur with certain hop oil constituents.

Keywords: Analysis, Emulsion, Hop oil, Sulphur compounds.