Review: dry hopping in brewing

Abstract

Dry hopping defined as the addition of hops or hops-products at the cold stage of the brewing process. The practice of dry hopping is currently used in many American styles of beer (IPA, APA, Imperial Stout), Belgian (Ali and Tripoli), traditional British (IPA, Extra Special Bitter), as well as other styles of beer with a developed aromatic component. The main volatile bitter and aromatic components of hops include terpenes (myrcene, humulene and betacarotene), which are characterized by “herbaceous” aroma. There are also linalool and geraniol, which give floral and fruity notes. Terpineol and pinene are making a resinous character. Currently developed special technology, the introduction of hops and the appropriate equipment for dry hopping: flower hops; hop suspension; hop pellets; semi-automatic methods. Dry hopping carried out to increase the “hoppy” aroma of beer and found application due to the increased popularity of small brewing in the world. Since dry hopping performed at relatively low temperatures thermal decomposition and volatilization of aromatic compounds is significantly reduced. This results in a higher concentration of these compounds in the finished product. The source of the aromatic properties of the beer is the polyphenols. In the process of dry hopping about 80-90% of polyphenols extracted during the first 12 hours. Flavan-3-ols increases perceived bitterness and astringency. Monomers and oligomers of flavan-3-ol play a role in the stability of taste, colloidal stability and foam resistance of the drink, have antiradical and antioxidant properties.