Barrels, Foeders, Wood Fermentation & Aging.

BY CHRIS MEADOWS, BREWMASTER @ ELKMONT EXCHANGE, KNOXVILLE TN Why ferment/age on wood?

In modern day, the intention of fermenting/aging beer on wood is to impact the character and flavor of the beer in a desired manner.

This process should yield a more complex and unique product than before its transformation. Why ferment/age on wood?

What type of influences are we talking about?

- original/natural - toast, char (ranging from light to heavy) - secondary characteristics like wine, ports, or spirits

Wine has a softer profile, which allows yeast or grains to shine, while spirits like bourbon may be overpowering and a dominant contributor. Why ferment/age on wood?

Oak is full of many flavorful and aromatic compounds and chemicals that, when added to beer, create another level of depth and complexity. Why ferment/age on wood?

- Some styles of beer are better suited for aging vs others

- Not all wood aged beers are high gravity

- Some people view wood as the fifth major ingredient in beer making

- Wood presents an ideal breeding ground for wild yeast and bacteria Why ferment/age on wood?

Set intention. If you’re going for a clean beer with no additional fermentation, the barrels may need to be steamed for sanitation purposes.

If you’re going for a wild or sour beer, wild yeasts and/or bacteria may need to be selected for a secondary fermentation to begin. Why ferment/age on wood?

- Brewers favor oak as the primary wood used for producing barrels for its:

- Strength - Resistance to decay - Water tight, yet slightly porous to air - Relatively high level of tannins

The right amount of tannins can add bitterness and mouthfeel. Too much can be harsh. Oak isn’t necessarily the best in every situation, but in terms of availability and consistent quality, it’s a winner. Why ferment/age on wood?

A few examples are:

- Furfural, which lends caramel sweetness - Eugenol, which is clove-like - Vanillin, the most recognizable flavor, tastes and smells like vanilla - Lipids, which constitute the oils, fats and waxes found in the wood, are responsible for oak lactones, which lend coconut and aromatic wood flavors.

These are the basic flavors found in all types of oak, and the ones we as brewers are looking for. Ways to age

There are many ways to age your beer including the use of barrels, puncheons, foeders, chips, spirals and staves.

This is often referred to as cooperage Barrels & Puncheons

A barrel, cask or tun is a water tight hollow container made of staves bound by wooden or metal hoops Barrels & Puncheons Barrels & Puncheons Barrels & Puncheons Barrels & Puncheons Foeders

A foeder is a Dutch word referring to a large wooden barrel set on end used for either long term fermentation or primary fermentation and inoculations. Sometimes spelled foudre, foedre

A foeder can range in size from home brewer to commercial scale. Foeders allow a slow ingress of oxygen into the beer that is easily supervised with the tasting valve. Foeders The high beer to wood ratio allows the beer to mature and develop whereas smaller barrels may progress sooner which may lead to over-acidification before the beer is fully developed. Foeders

Foeders also allow for greater capacity compared to the footprint barrels take up.

Because the beer is coming from one vessel, you will have a more consistent and reproducible product.

Foeders will also save on time and labor compared with racking multiple barrels or pulling multiple nails when sampling. Foeders

The world's largest foeder belongs to the brewers of the aperitif Byrrh, in France.

Though no longer operative, it once held up to 1 million liters, and required 200 trees over the course of 18 years to complete. Foeders Foeders Foeders Foeders Chips, spirals and staves

Oak chips are an effective way of modifying and adding flavor to your beer or wine - and chips are far cheaper and easier to manage than buying new or used oak barrels.

Remember, chips float! Most brewers place chips into a clean sterile hop bag and weigh the bag down with something heavy and inert.

Fitting a bag full of chips inside a secondary might not necessarily be easy depending on what you use for a secondary vessel. Some people add extra chips to barrels, while some utilize a stainless tank with a man-way door. Wood aged vs barrel aged

A lot of people use the term interchangeably. The simple difference is that wood aged can also include chips, staves and spirals whereas barrel aged implies the use of an actual barrel, puncheon or foeder.

Stored vs Aged beer – technically all beer rested in a wooden vessel or on oak chips is aging with the intention to welcome changes and transformations, whereas beer that is stored is typically in stainless containers like kegs with no intention of further evolution of the product. Wood aged vs barrel aged

How to increase extraction from the wood

- temperature - time - recirculation - pressure - surface area Wood aged vs barrel aged

Temperature: temperature swings allow the wood to “breathe,” which draws the liquid into the pores of the wood and out of them based on when it is warm or cold outside of the barrel.

Time: time impacts wood aging in a simple manner. The longer the beer is contact with the wood, the more impact the wood has on the character of the beer.

Recirculation: recirculation for the most part only happens in tanks or totes, and is a form of agitation to achieve a stronger flavor transfer. Wood aged vs barrel aged

Pressure: when pressure increases, flavor extraction increases.

Surface area: The surface to volume ratio gets smaller as the size of the barrel increases. As the size of the barrel increases, there is less liquid actually in contact with the wood. Blending

A good practice in wood aging beer is blending.

- Blending allows the brewer an opportunity to choose which characteristics to highlight. For instance in sour beer, blending is often used to mix highly acidic beers with less acidic beers.

- Blending also allows the brewer to have an opportunity for better consistency. For instance, if releasing a barrel aged beer each year, the brewer can choose to blend young vs older aged beers to work the product towards a consistent brand identity.

- In some circles, blending is viewed as the most important process of aging on wood. One bad apple could in fact ruin the entire bunch. Blending

How often can a barrel be used?

- Typically most barrels are used only once or twice before being retired, although this is not always the case. Keeping a stash of older barrels is a great way to begin a sour program.

- Foeders and puncheons are often used for several generations, especially in wild programs where yeast and bacteria can live in the wood and restart fermentation when filled again.

- Even when barrels are done with beer, they often find secondary uses as rain barrels, decoration, furniture or garden beds. Prepping

- it’s best to use freshly emptied barrels.

- If the barrel has been emptied a long time it may need to be opened up and scraped. Scraping the inside will remove blisters, crystal deposits and other debris that may be undesired. Prepping

sulfur dioxide – sulfur sticks which burn like incense inside a barrel, will act as a disinfectant to stave off a variety of unwanted microbes that might be native to the wood. Prepping

potassium metibisulfite & citric acid - The metibisulfite releases sulfur dioxide into the water and the Citric Acid increases the amount of SO2 in solution by lowering the pH of the water.

Lowering the pH can also keep out unwanted microorganisms. This solution will keep the barrel sound

*When you treat a barrel in this manner, you will be stripping some of the oak flavor from the wood. Things you’ll need in addition to cooperage

https://www.westernsquare.com/barrel-racks-breweries-1/ Things you’ll need in addition to cooperage

https://www.gwkent.com/bulldog-barrel-transfer-tube.html Things you’ll need in addition to cooperage Things you’ll need in addition to cooperage Things you’ll need in addition to cooperage

https://www.gwkent.com/barrel-fermentation-plus-bungs.html Things you’ll need in addition to cooperage Things you’ll need in addition to cooperage Things you’ll need in addition to cooperage

https://www.gwkent.com/short-strainer.html Things you’ll need in addition to cooperage

https://www.gwkent.com/2in-sight-glass-tc.html Things you’ll need in addition to cooperage

https://www.gwkent.com/turbine-flow-meter.html Things you’ll need in addition to cooperage

https://www.gwkent.com/hoop-driver-for-oak-barrel.html Things you’ll need in addition to cooperage

"Time does not respect what is done without it." Reputable sources Reputable sources Reputable sources Advice

When brewing beer for wood aging, it is important to note that you will end up with less volume than when you began.

Evaporation, leakage, soaking into the wood.

Always intend to brew a little extra for options when blending the final product. Advice

Top off barrels often, especially after sampling or fixing a leak.

Aging beer in barrels is 100% about the ‘controlled’ oxidation over an extended period of time.

Too much head space in the barrel could cause the beer to oxidize at a rapid rate which could ruin that stout, or over-acidify that sour. Advice

Expect occasional failure.

Things go wrong.

Barrels leak, bungs blow off.

The wrong bugs get in https://www.keystonefermentationsupply.com/ https://www.riverdrive.co/

https://www.foedercrafters.com/

https://www.barrelsdirect.com/

https://www.thebarrelmill.com/

https://www.halfyankeeworkshop.com/blogs/news/aging-beer-with-wood https://www.morebeer.com/articles/Beer_Wood_Oak