The characteristic popping sound and puff when opening a bottle both are apparent thanks to carbon dioxide. The process of carbon dioxide saturation of beer is called carbonation. The factory breweries use special vessels–fermentation tanks, in which beer ferments under high pressure. But this is an expensive technology. The most popular way to make carbonated beer at home is to use a primer—a substance that contains sugars, which cause repeated fermentation.
You can determine the degree of beer carbonation by a number of bubbles in a glass with a freshly poured beverage: the more bubbles there are and the faster they are, the more beer is saturated with carbon dioxide. The second indirect sign is the height of the frothy cap, but the quality of malt and mash affects the foam more than carbonation.
You can also artificially carbonate homemade beer using a carbon dioxide cylinder (forced carbonation). This requires some special equipment: kegs, fittings, the cylinder itself and a reducer. Also every once in a while you’ll have to fill the installation with carbon dioxide.
An example of the equipment used to carbonate beer in kegs
The advantages of this method: beer turns out transparent and without any yeast sediment; transporting kegs on long distances is also much easier. The main disadvantages: the carbonating equipment is not cheap and requires careful use; after bottling beer from kegs it’s store life will be a few weeks tops.
The most simple and cheap method of carbonating homemade beer is adding some sugars to the fermented wort in order to cause quick repeated fermentation. As a result, your beer will become naturally carbonated. The only disadvantage of this method is that there will be a sediment layer at the bottom of the bottle, and you won’t be able to get rid of it with tools at hand.
How to Prepare a Beer Primer
To perform carbonation brewed fermented beer is decanted into a clean fermentation vessel which contains one of the 5 types of primer.
- Beet sugar or honey. That’s the cheapest option. You’ll need 0.25 oz/7 grams of sugar or 0.17 oz/5 grams of liquid honey per 1 liter of beer. The most significant disadvantage of this method is that the beer will almost certainly have a kvass flavor.
Sugar is the worst primer
- Fructose. Sugar obtained from sweet fruits, not beet. The main advantage of fructose carbonation is that there’s much less kvass flavor. The correct dosage is 0.28 oz/8 grams per 1 liter of beer.
- Dextrose (glucose). Under these two terms hides one substance—dextrose is glucose in powder form. Carbonation of beer with dextrose (you’ll need 0.28 oz/8 grams per 1 liter of beer) allows obtaining even lesser kvass flavor compared to sugar and fructose.
It’s easier to add syrup and there’s lesser risk of infecting the beer
Sugar, fructose, and dextrose can be added in a dry form directly to the bottle but in order to prevent infecting the beer with pathogenic microorganisms and accelerate fermentation it’s better to prepare syrup: mix the correct amount of primer with the same amount of water, bring to a boil, simmer for 5-10 minutes, skimming off the foam. Cover the prepared syrup with a lid, cool it to a room temperature and then add to the beer.
- Malt extract (concentrate).You can buy it in brewery stores. It’s a sugary and boiled wort which dehydrated to the full. It is preferable to use a not hopped concentrate. To carbonate 1 liter of beer, you’ll need 0.3-0.4 oz/9-12 grams of extract (the higher the quality, the less you’ll need). Boiling the syrup following the standard method described previously is preferred. Using malt extract doesn’t give any side smells and flavors. The main disadvantage is that you’ll need to buy the concentrate separately.
- Young wort.The best option. Usually by “primer” experienced brewers mean carbonation of beer with wort because this allows obtaining clean taste and the primer itself can be prepared at home.
Technology: during the last minutes of brewing (after adding fragrant hops) pour 10% of the wort into a clean, sterilized vessel (for example, a jar), hermetically seal it and leave in a fridge. After the beer has fermented the wort is added for carbonation and mixed.
During carbonation with wort, the most important thing to remember is that you need to leave the primer
Beer and primer are closed under an air lock for 30 minutes to activate fermentation. After that, the beverage is bottled, sealed with corks and transferred for maturing. Any brewer’s yeast left in the wort will cause repeated fermentation which will enrich the beverage with carbon dioxide. The time required for carbonation depends on the recipe and desired degree of carbonation. It usually takes about 14-35 days.