Can I Add Fruit To Home Brew - Can I Add Fruit During Primary Fermentation

How to Add Fruit to Home Brew Beer and Cider

The 5 things you need to know about adding fruit to beer or cider in primary fermentation.

We’ve never made a secret of the fact that we’re fans of kit brewing – the process of making home brew beer or cider from extract kits. And one of the reasons that we love kit brewing is that there is still plenty of room to experiment with process and ingredients to make your own signature brews.

One of the common questions we get asked is ‘how do I add fruit to my homebrew beer or cider’ – so we’re sharing the 5 things you need to know about adding fruit in primary fermentation. 

What fruit can you add and how much to add

When it comes to what fruit to add in primary fermentation there are no rules. The most common fruits that come up in conversation and questions are Blackberries and Raspberries, Feijoas, stone fruits like Apricot and Nectarine, citrus fruits and even Mango and Passionfruit. 

One of the keys to success will be selecting a combination of ingredients that will compliment each other or work well together. When it comes to kit brewing, we would suggest that you will want to have brewed the kit you plan to you by itself first, so that you understand the flavour profile of the brew alongside any other ingredients like hops that you may also be using.

Don’t be constrained to just one fruit. If you choose, there is no reason why you can’t use more than one fruit in each brew.

Once you have chosen the fruit that you want to use, the next question is how much of it to use. And again, there are no rules or a right or wrong answer.

The question will be how strong you want the flavours and aromas from the fruit to be. Do you want them to be a dominant element of the flavour profile, or an accent that compliments the existing flavours and aromas? You will also have to balance this with the flavour and aroma profile of the fruit – is it by nature a very subtle flavour and armoa or does your chosen fruit have strong and intense characteristics. Both will be determinants in how much fruit you use.

Someone once told me that brewing is half meticulous process and calculated decisions and half mad scientist. Given some of the ambiguity in determining how much fruit to use you will most likely be wearing your mad scientist hat here.

To give you an example, in a recent brew I used 4.2KG of fresh Feijoas with an Apple Cider Kit. I would say the result was an Apple and Feijoa Cider where the flavours would have been 40/60 in favour or the Feijoa. In other words, the Feijoa characteristics became a more dominant element of the flavour and aroma profile. If you watch the video the one change we would make would be to use the sweetener in the kit which we left out of this brew. The Feijoas create a tarte finish and while very nice a hit of sweetness would have set it off nicely. 

How to prepare fruit to be added to fermentation

How you prepare the fruit is a key step. Here you are ensuring that you are not introducing bacteria that could ruin your brew and you are ensuring that you maximise the transfer of flavour and aroma characteristics to your brew.

The method that we favour is to peel if required and then place the fruit in a saucepan of water. Bring the contents to the boil and then keep on a slow boil for 15 minutes.

This process does two things. First you are killing any bacteria that could be on the fruit before you add it to your brew. Second, you are starting to break the fibres of the fruit down, and extract the natural sugars and flavours, which will optimise the transfer of flavour and aroma characteristics.

If you take this approach, complete these steps directly before you add the fruit to the brew. And when you add the fruit to the brew also add the water that you used to boil the fruit in, which will now contain sugars and extracts from the fruit.

As an alternative you can prepare the fruit, for example peel and cut up as required, and then freeze. The process of freezing is intended to kill bacteria. I have seen videos where people talk about freezing and defrosting 2-3 times. The process of defrosting and re-freezing is intended to begin breaking down the fibre of the fruit.

We favour the approach of boiling as it seems like less effort to us, and you can do so directly before you add to the brew which seems like a more logical approach for reducing bacteria. 

How to add fruit to your fermentation

Once you have prepared your fruit, you can add it to the brew while in the fermenter in much the similar way you would add hops when dry hopping. Two basic options you could take would be to use a hop sock or to simply add the fruit loose.

If you watch the video embedded in this article, you will see that we added the fruit directly to the fermenter without a hop sock, in other words loose. The argument for this approach is that you increase the contact area between the brew and the surface of fruit and therefore increase the transfer of sugars and flavour and aroma characteristics. The argument against this approach is that you can have smaller pieces of organic matter in your brew to manage. In our experience if you have a fridge that you can use to cold crash the brew and you use a bottling bucket you can easily overcome the downsides presented by this approach, which we generally favour.

The alternative approach is to place your fruit in a hop sock. This will help you contain the fruit and make it easy for you to remove the pulp when it comes time for bottling. This approach is particularly useful if you only want the fruit in your brew for a short period of time. 

When to add fruit to fermentation

There are a myriad of options to play with here. The easiest way is simply to add the fruity to your beer or cider during primary fermentation.

If you take this approach, you could add the fruit from the very outset, add the fruit mid fermentation or at the very end of fermentation. In general, the earlier you add the fruit the greater the transfer of aroma and flavour characteristics you will achieve. When it comes to process this is another key area where you can experiment and establish your own personal preferences.

The other option you have would be to rack the brew off into a second fermenting vessel once fermentation is complete and place the fruit into the brew for a secondary fermentation process. If you did this the other major variable you have to play with would be the length of time you allow the secondary fermentation to run. 

The impact of adding fruit to your brew and alcohol content

Remember that fruit contains natural sugars and therefore when you add fruit during a primary or a secondary fermentation process you are providing another source of fuel for yeast.

You can most likely expect a higher alcohol by volume if you add fruit but it could be harder to accurately calculate your final ABV.

When you are measuring ABV you typically measure changes in gravity to estimate the alcohol content. Gravity measures the volume of sugars which are dissolved in the brew. Fruit contains sugars, which are extracted into the brew over time. Your original gravity measurement won’t necessarily reflect the additional sugars which will be contributed by the fruit you have added to fermentation. A very likely scenario is that your ABV will be higher than what you expect.

In summary you can easily add fruit to your primary fermentation for beer and cider brews. And adding fruit to fermentation is a great way to experiment and create your own signature brews.

Once you have chosen the fruit you want to use, the most important step we would encourage you to think about is how you prepare you fruit to be added to your brew. It is these steps that ensure you are hygiene and optimising the transfer of flavour and aroma characteristics.

We would also suggest you consider how long you store or keep brews you have added fresh fruit extracts to. As a conservative measure we consume any brews we have made using fresh fruit within 3-months.

And as a final note if you are thinking about experimenting with flavours don’t limit your thinking to organic ingredients. Although the process you use might be slightly different there are plenty of ingredients like chocolate, liquorish or coffee which can compliment selected beer styles.