MBAA TQ https://doi.org/10.1094/TQ-58-1-0308-01 | VIEW ARTICLE
Martin Biendl (1), Christina Schmidt (1), John Paul Maye (2), and Robert Smith (2). 1. Hopsteiner, 84048 Mainburg, Germany. 2. S.S. Steiner, Inc., New York, NY 10022, U.S.A.
To investigate their typical aroma profiles, commercial samples of New England India Pale Ale (NEIPA) were analyzed by headspace GC‑MS and GC-MS/MS methods. As result of this study, the NEIPAs showed record levels of nonpolar terpenes like myrcene (up to 26 mg/L), alpha-humulene (up to 2.3 mg/L), or beta-caryophyllene (up to 1.6 mg/L). Polar monoterpene alcohols like linalool (up to 2.2 mg/L) or geraniol (up to 0.6 mg/L) and thiols like 4-mercapto-4-methylpentan-2-one (up to 150 ng/L) were also present in relatively high concentrations, which can only be achieved in an extremely dry-hopped (West Coast) IPA. Such high concentrations clearly exceeded the corresponding odor threshold values of these hop aroma components. Reduction in aroma compounds after haze removal by centrifugation proved to be dependent on polarity. Average losses of nonpolar terpenes were in the range of 85% (for myrcene) to 79% (both for alpha-humulene and beta-caryophyllene), whereas more polar components like ketones and esters were reduced to a lower extent (41 to 25%). Monoterpene alcohols and thiols experienced little to no loss in concentration after centrifugation. During storage for 6 months at 5°C the concentrations of thiols and terpenes decreased by more than 50%, but monoterpene alcohols exhibited almost full stability within this period. Such a storage behavior of hop-derived aroma components is not unusual and comparable with other beer styles.
Keywords: New England IPA, NEIPA, myrcene, 4-mercapto-4-methylpentan-2-one, geraniol, beta-citronellol