The Defects Wheel for Beer aids in quick and accurate identification of off-aromas and flavors. This quick and accurate sensory identification tool is indispensable for brewers, beer merchants, and consumers. For the brewer, early corrective identification and action can often solve a serious problem before the fault becomes irreversible. For the beer merchant, avoiding losses associated with defective beers improves profit margin. Beer consumers will use the defects wheel to learn more about beer off-aromas and flavors so that rejection is based on genuine defects, rather than unfamiliarity. Each wheel is a complete reference to common defects which may occur, and includes: -Molecule responsible -Chemical formula -Main origins -Typical concentration in product -Approximate aroma threshold -Possible causes -Possible treatments -Possible prevention