​​​High Geraniol Levels in Chinese Qingdao Flower Hop

MBAA TQ https://doi.org/10.1094/TQ-59-1-0409-01​  | VIEW A​R​TICLE

Enda Winters. School of Engineering & Physical Sciences, Brewing and Distilling, Heriot-Watt University, Edinburgh, Scotland​

Abstract
 
China is the largest beer consumer in the world and the third largest grower of hops after Germany and the United States. Chinese hops have primarily been used for bittering beer, with little known about their aroma potential. The Qingdao Flower hop makes up approximately 90% of the Chinese hop growing area. This study assesses the Qingdao Flower hop for aroma compounds and their potential use in dry-hopping beer. The lupulin glands of hops contain the alcohols, esters, sulfur-containing compounds, sesquiterpenes, oxygenated sesquiterpenoids, and aldehydes that give dry-hopped beer their pleasant aroma. Unfortunately, information on the presence of these important aroma compounds in Qingdao Flower hops is lacking. With the understanding that both terroir and processing effect hop quality, the study sourced hops from China’s two growing regions in the northwest of the country and from multiple growers. It was found that the essential oil fraction of Qingdao Flower hop is relatively low; however, the hop is rich in desirable aroma compounds. In particular, a grower from the Gansu Region of China produces a Qingdao Flower hop that produces beer that is high in the sesquiterpene geraniol, one of the most impactful aroma components found in hops. Breweries can use this analysis to explore the possibility of producing an IPA with domestic Chinese hop varieties. However, more work is needed on the processing and growing conditions to ensure the highest quality hops are produced in China.​