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====The Freshening Power of the Hop====
Also known as "dry hop creep", it was first discovered in 1893 by Brown and Morris that dry hopping increases ABV of beers and dries them out. It was proposed that the likely releases cause is the release glycolytic enzymes that break down starches into sugars that viable yeast can then ferment. Brewers normally aim to control the final alcohol percentage in a beer through brewhouse operations rather than postfermentation dilutions with lower/higher alcohol beers or water. This approach to brewing is called "brewing to final gravity." Due to the need to have a predictable ABV for government regulatory reasons, unexpected fermentation is, therefore, a concern for many breweries <ref name="Kirkendall_2018">[https://www.tandfonline.com/doi/abs/10.1080/03610470.2018.1469081?journalCode=ujbc20 The Freshening Power of Centennial Hops. Jacob A. Kirkendall, Carter A. Mitchell & Lucas R. Chadwick. 2018. DOI: https://doi.org/10.1080/03610470.2018.1469081.]</ref>.
Historically, there have been two studies published on the phenomenon of hops releasing glycolytic enzymes that break down starches during dry hopping: [http://barclayperkins.blogspot.com/2018/03/why-dry-hop.html Brown and Morris (1893)] and [https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.1941.tb06070.x Janicki et al. (1941)]. More recently, several researchers and brewers have rediscovered this phenomenon. Brown and Morris (1893) discovered that hops could break down maltodextrin, but failed to extract the enzymes from the hop plant material and hypothesized (probably incorrectly) that tannins were inhibiting the enzymes. Janicki et al. (1941) came to similar conclusions regarding the enzymes and tannin inhibitors, and they also concluded that the enzyme activity was independent of hop variety, geography, age, storage conditions, pH values between 4.1 and 4.8, and that one or more additional unknown factors were at play <ref name="Kirkendall_2018" />.