Personally, I love the convenience of kegging beer. I put 12 bottles aside for competition, bottle them, and then keg the rest. So much time is saved on washing and sanitizing, not to mention capping, labeling, sorting, and WAITING for the beer to carbonate. Ugh…

However, I’ve always found that the bottle-conditioned beer tastes better than the kegged. Perhaps I get a bit of oxidation in the keg, I’m not sure, but bottled samples always seem more flavorful to me. Therefore, when I’ve crafted a real beauty of a beer, I sometimes feel that it’s necessary to take the extra time and bottle it all.

Other than time, the only problem with bottle conditioning is when you patiently wait the two or three weeks, then open the bottle and discover that you’ve missed out on the level of carbonation. Nothing seems to ruin the moment of opening the first bottle then having no mist form in the neck of the bottle after removing the cap, or that pitiful little wisp of CO2 release associated with an under-carbonated beer. In a keg, this is no problem, simply add more gas (or if over-carbonated, take some out) and in seconds you’re ready to go. With bottles, you have only one shot at carbonation, so it’s worth it to take a reasonable amount of care.

The other thing to consider is that the wrong CO₂ level in beer is the one thing that all people recognize as a fault whether they’ve taken their BJCP exam or not. Carbonation and a well-formed head is the first thing you see and first impressions are important.

There are essentially three variables that affect carbonation levels in your finished product:

Yeast – amount, health, strain, etc.

Temperature – the colder the beer, the more carbon dioxide is dissolved prior to priming.

Mass of priming sugar used to bottle condition the beer.

When it comes to yeast, it is really important to be absolutely sure that the beer contains enough healthy yeast after secondary fermentation to do the job of carbonating your beer. Think back to the brew day… Did you use a starter? Was there a long lag time? Was the fermentation sluggish?

Was there a healthy head of kreusen during primary fermentation? Did you condition or lager for an extended period of time? If you doubt the vitality of the yeast for any reason, then add a small active starter in place of priming sugar (this method of carbonation is called kreusening) prior to bottling. This is a common method for carbonating German beer because the Reinheitsgebot forbids the addition of sugar. However, purity laws aside, kreusening is a perfect method for bottle conditioning extremely high alcohol beers like dopplebocks or beers lagered for an extended period of time such as Oktoberfests.

How much priming sugar you should add depends on the temperature of the beer at bottling time as well as the style of beer you are brewing. If you are brewing ale, chances are that you have let it ferment and condition at room temperature. If this is the case, then the beer starts off with very little CO2 disolved in it compared to a beer that was lagered, or conditioned in the cold. Therefore you need to add more priming sugar to warm beer than to cold, lagered beer. Also, some styles require much less carbonation than others. For example, English ales are typically less carbonated, almost to the point of being flat, and German hefeweizens require a fair bit of carbonation, reminiscent of champagne. When calculating the amount of priming sugar to add, I use two tables and a graph from the July/August 1996 issue of Brewing Techniques.

Simply measure the temperature of the beer prior to priming with a thermometer in order to determine the amount of CO2 dissolved, then use the graph below to determine how much priming sugar is required per gallon of beer.

One of the biggest sources of error in determining the amount of priming sugar is that many brewers measure volume rather than mass. The density of priming sugar varies depending on the humidity, whether it is tightly packed or loose, etc. Therefore mass is the most dependable measurement to use when priming.

If you prefer to measure in grams, simply multiply the number of ounces by 28.35.

If you plan to only bottle enough for competition and keg the rest, then simply transfer some of your beer to a1 U.S. gallon growler, and weigh out the amount of priming sugar required. I always draw off some of the beer into a small pot, add the priming sugar, bring to a boil, cool, then add back to the beer prior to bottling. This way, the beer isn’t diluted. Always allow your beer to bottle condition at room temperature so that the yeast will be active.

Happy carbonation always.