Priming and Bottling
Once the yeast have finished doing their thing and your beer is finished fermentation, it is time to bottle. Although it is necessary for transportation, bottling beer also serves the important purpose of carbonating and conditioning it.
The process of priming your beer simply adds more sugar for the left over yeast to convert into Carbon Dioxide (CO2). The sugar that was previously added through the brewing process was included so that it could be converted to alcohol and the resulting CO2 allowed to escape through the airlock. The sugar added for priming is there only so that the small amount of remaining yeast can convert it to CO2 that stays in solution until you open your beer.
The ways that this can be achieved are all variations on a couple of general themes:
Bottle Priming – The simplest way to prime your beer bottles is by adding a small amount of sugar into each bottle as the beer is poured in. Measuring spoons exist allow for more accurate addition of this sugar. Alternately your local homebrew shop will also sell ‘carbonation drops’ which are a small amount of pre-measured sugar in a solid form that allow for either one or two drops (depending on bottle size) to be used.
The downside of both methods of bottle priming is that the amount of sugar used is only an approximation and is often not accurate.
Bulk Priming – The process of Bulk Priming involves the use of another plastic container (tub, bucket or fermenter) to add a pre-mixed sugar solution in with the beer. As this additional (unfermented) sugar is mixed through the whole beer batch, this has the benefit of being a much more even distribution. As we already know the size of your whole batch of beer, it is also possible to calculate the amount of sugar required to obtain your desired level of carbonation. This results in a greater level of control and the results are far more accurate across the batch.
If you are going to be using different or unusual sized bottles, bulk priming will also have the added benefit that you won’t have to think about how much sugar should be in each bottle because the priming sugar has already been added.
The process of bottling beer is a reasonably simple one and due to the generally repetitive nature, one that is best performed with a beer from a previous batch on hand.
When transferring your fermented beer to bottles, it is important that you take care to not shake up the beer too much as it is going into the bottles as this oxidization can cause your beer to turn stale and introduce flavors similar to wet cardboard to the finished product.
The process itself is a reasonably simple one, as long as you have the correct equipment. In order to make your life far easier, part of your basic homebrewing kit should be a small plastic bottling wand. These connect onto the tap of your fermenter or a piece of plastic hose and work by controlling the flow of beer through a small piston at the bottom. This allows for easy swapping of bottles without having to turn the fermenter tap on and off or spill beer everywhere.
The process of transferring you’re finished, fermented beer to its final home is:
- Sterilize everything that will come in contact with the beer using a no-rinse sanitizer and allowed to dry. This includes:
- The container that you are using for bulk priming (if applicable)
- Any other priming equipment
- All Bottles
- Bottle lids
- Your bottle capper
- If you are bottle priming, add the priming sugar to each bottle. If you are bulk priming, add the sugar solution and beer to the priming vessel
- Insert your bottling wand to the fermenter or container that your beer is in and turn on the tap
- Slide the bottling wand to the bottom of each bottle and fill with beer from the bottom. You should aim to leave a little space at the top of each bottle though to allow for pressure and to avoid ‘bottle bombs’ – See below
- Put the cap onto each bottle using either a hand or bench capper
Avoiding bottle bombs:
One word of caution that is often expressed to beginning brewers is around the importance of avoiding ‘bottle bombs’. This is simply when a bottle explodes due to the amount of Carbon Dioxide (CO2) inside the bottle creating too much pressure for the glass and causing it to explode. This situation is not one that you should be overly concerned about and is easily avoided by making sure that:
- The fermentation process has has finished before bottling beer, and
- You are not adding too much priming sugar
Has my beer finished fermenting?
The clearest way to be sure of this is to take a reading with a hydrometer and confirming that the specific gravity (SG) of your beer is static over a few days – This means that the yeast have finished doing their thing.
An even easier way to be sure is to follow the advice supplied under the fermentation guide and just leaving the beer in your fermenter for longer. Anything less than 4 days and the yeast will still be working away, 7 days could go either way but if you leave it in the fermenter for 10+ days, you should be pretty safe.
Too much priming sugar
As well as granting the ability to control the level of CO2 in the final beer, bulk priming has the advantage of taking out and doubt in regards to whether a beer has been primed.
Avoiding bottle bombs is another reason that I recommend adding priming sugar to the bottle before the beer. That way you can see whether each bottle has been primed before the beer is added, just be cautious to only add the priming sugar to each bottle once!
Bottle conditioning your final product can be both the easiest and the most difficult part of the whole homebrew process. On one hand it involves doing nothing but just waiting for the last stages to happen by themselves inside the bottle, on the other this means that you need to just wait until it is ready. As a rough guide for an ale beer, this will take from around 3 weeks but longer is better. To allow the yeast to continue to convert your priming sugar to CO2, you should store the newly bottled beer at room temperature for the first 7-10 days. After this time it is fine to transfer to a colder place to finish conditioning. You will even find that if you store it in the fridge for a couple of days before opening the bottle, much of the sediment will settle to the bottom of the bottle.
In most cases your beer should be carbonated after about a week in the bottle. Through this time the remaining yeast in the beer works on converting the priming sugar into CO2 which is then trapped in solution. This is different to the previous conversion activity because the lid stops the gas from escaping.
After about another 2 weeks you should be able to open your first bottle and have a try. Be warned that at this point though, many beers are still developing and as such can taste sharp and ‘green’. With additional time in the bottle, the flavors will start working together better and the overall taste will settle into something more enjoyable.
For your first few, I encourage you have a try after only a couple of weeks in the bottle in order to taste the difference as it conditions. If you are anything like me you will be waiting (im)patiently to taste the new product anyway. In fact my very first brew was nearly half gone after only 3-4 weeks in the bottle because I was so excited, and most of my current brews are gone within a couple of months.