|Alcoholic fermentation, also referred to as ethanol fermentation, is a biological process by which sugar is
converted into alcohol and carbon dioxide. Yeasts are responsible for this process, and oxygen is not necessary,
which means that alcoholic fermentation is an anaerobic process. Byproducts of the fermentation process include
heat, carbon dioxide, water and alcohol. In this case, we’re focusing on the latter.
Humans have been using the process of ethanol fermentation for millennia. The ancient Greeks were known for
their mead production, which was produced by fermenting honey and water. In the meantime, though, honey has
taken a back seat to other foodstuffs, most commonly grains (for beer and spirits) and grapes (for wine).
Additional base products include other fruits, such as berries, apples and so on, rice (for sake) and beyond.
Native yeasts (also known as wild yeasts or ambient yeasts) are naturally present on fruit skins and in cellars.
When a booze producer chooses to let their juice ferment with native yeasts, this means that they’re simply relying
on the naturally occurring yeasts found on the raw materials and in the cellar where the fermentation is taking
place. When fermentation is done naturally, it tends to take much longer, which isn’t necessarily a bad thing.
When a producer chooses to use cultivated yeasts, this means that a specific strain of yeast is sought out,
purchased and added to the raw materials to kick-start fermentation. Yeasts come in all different flavors and
makeups. Purists will argue that using cultivated yeasts takes away from the authenticity of a raw material, though
the fermentation process will generally take much less time and the result is often more predictable and consistent.
Alcoholic fermentation is the process of using yeasts to convert sugars into alcohol. Distillation is a process used
to higher-ABV beverages from already-fermented base products. (For example, the distillation of beer wort creates
whiskey, while the distillation of wine produces brandy.) All alcoholic beverages undergo fermentation, thought not
all fermented beverages are distilled.
Wood aging is all about surface-to-volume ratio. The smaller the barrel volume, the larger the surface area, and
the faster it ages,” says Boyce. So start with a small barrel and work your way up. “I had a 12-gallon oak barrel
that I aged about 20 beers in before I ever got my hands on a [53-gallon] bourbon barrel,” Porter says. Don’t
expect to age it as long as your local brewery would, either. Taste regularly and decide for yourself when it’s
ready, but it could be on the order of just a couple weeks..
Please remember that Beers that contain a minimum of 8-9% ABV or higher are better suited for barrel aging than
their lower ABV counterparts. There are a number of reasons for this. First, higher ABV beers can withstand the
harsh environment of a barrel. These beers are generally aged in barrels for approximately 6-9 months, or even
longer. The higher alcohol content acts as a barrier for microbes that would normally turn beer bad. Second, beer
styles that have higher ABV are styles that can incorporate oxidized flavors into the beer. While keeping oxidation
at bay is the norm for most beer, it’s an accepted part of the beer style for higher ABV beers like Barleywines,
Imperial Stouts, and Belgian Quads.
Hope you found this month's column of interest. If you have any questions about beer or brewing
or just want to submit a word for me to discuss here just e-mail it to me.
Thanks and Cheers!
|Basics of Fermentation / Barrel Aging Homebrew
|A new column by
|Jack O'Reilly attended the
famous Siebel Institute/ World
Brewing Academy in Chicago.
|I'm very excited to be part of the BeerNexus team. I think my many years in the beer
business both as a brewer and manger will enable me to explain and investigate
many topics of interest for those who really love craft beer.
Hope you join me every month.
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|Techniques and insights
for the serious ceft beer
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