Presenter: John Stewart, New Holland Brewing Company, Holland, MI. Coauthor(s): Molly Browning, New Holland Brewing Company, Holland, MI.
It is becoming increasingly popular for wineries to use micro-oxygenation machines on wine held in tanks to mimic the results of oak barrel maturation. Oxygen is slowly injected at a very low dose ranging from 0.5 mL/L/month to 2 mL/L/month through a ceramic membrane. It is claimed that this process oxidizes tannins and creates a softer, more rounded wine similar to what is found after oak barrel aging. As more and more breweries are aging beer in oak barrels, it was sought to determine if micro-oxygenation could be used to achieve similar results with beer. A high-gravity ale was aged in both 5- and 55-gal previously used flavor-neutral American oak barrels and a stainless-steel tank equipped with a micro-oxygenation unit. Spectrophotometer and gas chromatography analysis of polyphenolic and ester compounds of the micro-oxidized, oak aged, and control beer were performed to compare oxidation of these compounds.
John Stewart has been a member of MBAA since 2007. In fall 2010 he attended the MBAA Brewing and Malting Science course. In 2006 he began his career in brewing with New Holland Brewing Company after graduating from Grand Valley State University with a degree in biology. John is currently the QA/QC manager at New Holland Brewing Co.