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Fermenting Under Pressure

Fermenting Under Pressure

Fermenting under pressure allows you to ferment faster and at higher temperatures.

What is fermenting under pressure?

When yeast is fermenting, it produces CO2 gas. Normally the gas will escape through a bubbler. With pressure fermenting, the fermenter’s CO2 gas is not realised and naturally pressurizes the system. The CO2 is eventually absorbed by the beer, and the beer becomes carbonated.

You will need a fermentation vessel that can handle the pressure, so a brew bucket is out of the question. The vessel should handle around 2 bars of pressure and have a safety blow-off valve. The blow-off valve will ensure that the pressure does not exceed the vessel’s maximum pressure. You will also need a regulator valve to regulate and monitor the pressure.

Two options for a fermentation vessel are a Corny Keg and a Fermzilla.

  • CORNY KEG – You must adapt the Corny Keg and add a regulator valve. This is easily done using a ball lock quick connect. The downside is monitoring the progress. There is no way to visually see the progress or even an infection.
  • FERMZILLA – A better option is a Fermzilla. These are purpose-made for fermenting. Being completely clear plastic, you can easily see your beer brewing. There are loads of options and accessories, so they can do loads more than ferment under pressure. Just ensure you get a Fermzilla that can take the pressure, as there are options that don’t.

Benefits to pressure fermentation.

  • Brewing faster.
    You can ferment at higher temperatures than usual, enabling quicker fermentation.
  • Oxidation risk is significantly reduced.
    Pressurizing the fermenter effectively seals the system, minimising the possibility of oxygen infiltration.
  • Reduce Off Flavours
    By reducing ester synthesis and yeast-derived off flavours during fermenting under pressure, a cleaner fermentation can occur at higher temperatures than usual.
  • Closed pressure transfer.
    When the tank is pressurised, it enables entirely sealed, oxygen-free transfers into the keg.
  • Carbonate in the fermenter.
    Who wouldn’t want a beer that is totally carbonated by the time it is ready for transfer? That is possible by fermenting and cold crashing under pressure.
  • Save on CO2
    You will be utilizing the natural CO2 produced by fermentation. This significantly reduces the amount of CO2 normally needed.

The introduction to Fermzilla Starter Kits

Geterbrewed stocks a wide range of Fermzilla equipment. Our latest Youtube video shows how a 35-litre Fermzilla starter kit works and what extra pieces of equipment you will need to ferment effectively under pressure.

Fermzilla 35 litre starter kit

The Fermzilla pressure kit comes with a float and dip tube. This attaches to the beer-out carbonation cap. The ball lock connector with the 2 bar pressure release valve/spunding valve fits onto the gas carbonation cap.

You can also dispense straight out of the fermenter. The benefit to fermenting under pressure means you can brew NEIPA, IPA’s and hop-forward beers without the risk of oxidising.

The Fermzilla range allows you to view the fermentation take place and is significantly cheaper than Stainless Steel uni tanks. This is the introduction to a series of blogs on fermenting under pressure, but if you’re interested in buying a starter kit we have added the product links below.

Pressure Release Valve 2 bar / 30 psi

Fermzilla – lots of sizes available links below to 35 litre version
https://www.geterbrewed.com/fermzilla-35-litre-starter-kit

Fermzilla Pressure Kit
https://www.geterbrewed.com/pressure-kit

Ball Lock Connectors
https://www.geterbrewed.com/ball-lock-disconnect-1-4-mfl-liquid
https://www.geterbrewed.com/ball-lock-disconnect-1-4-mfl-gas

2 Bar Pressure Release / Spunding Valve
https://www.geterbrewed.com/pressure-release-valve-en

Geterbrewed stock a range of homebrewing products that facilitate fermenting under pressure. We will be featuring a range of new innovative products and videos to showcase this topic as we see the homebrewing industry moving more towards this type of fermentation.

We want to highlight a range of products that we feel make it simple to get you started with fermenting under pressure, the Fermzilla range is an economical way of pressurised fermentation, and you can also see through the bubble and watch fermentation taking place. A considerable saving on stainless steel uni tanks.

Check out our video about a fast lager fermented under pressure.