Ask Mr. Wizard

Brewing With Fruit – How Much?


Nathan Pyles - Waco, Texas asks,

When brewing with berries how much should be used for a 5-gallon (19-L) batch? I am planning to make a raspberry wheat beer.


Fruit beers run the gamut from being so subtle that the fruitiest part of the beer is the name, all the way to the extreme where the intensity of the fruit approaches a wine and the consumer is surprised that they are drinking beer. I personally like fruit beers that don’t leave me guessing if the brewer forgot to add the fruit during the brew.

I like to think about recipes in terms of percentages. One pound of fresh fruit per gallon of 12 °Plato (1.048 SG) wort contributes about 10% of the extract. This is enough fruit to leave no doubt that the beer contains fruit, but not so much to really knock your socks off. Beers with 20–30% of the extract derived from fruit are really pretty fruity! These beers contain 2–3 pounds (0.9–1.3 kg) of fruit per gallon (3.8 L) of wort.

So now you have an idea of how much fruit to add to your wheat wort. The next question is equally important, and that question has to do with the method of addition. Some brewers like to add fruit to the kettle to satisfy their quest to sterilize everything going into fermentation. But boiling fruit is not necessary and is certainly not in line with how wine is made. Another technique is to add fruit to the beer following primary fermentation. This method initiates a second peak of fermentation activity that typically lasts only a few days. Whether you add the fruit to the kettle or to beer after the primary, most if not all of the fermentable sugars will be consumed by yeast.

The fact that fruit beers often times are not sweet means that much of what most people associate with fruit is lost. If you buy a dry red wine and expect to experience the fruitiness of Welch’s grape juice you will be very disappointed indeed. Some fruit beers are sweet, but there are some tricks of the trade required to maintain the sweetness, and increasing the amount of fruit added to the beer is not one of these. Some brewers of these sweet or semi-sweet fruit beers arrest the fermentation after a point to retain some of the fruit sweetness. Pasteurization is the method of choice for commercial brewers because it helps to ensure that the residual fermentable extract is not fermented after bottling. Winemakers often times use sulfites to arrest fermentation when producing sweet wines, and this method can also be used by brewers. If you have residual sugar in the beer, bottle conditioning is clearly not an option. Pasteurization can be performed at home if you are feeling especially adventurous. This is a very broad topic of discussion that I will leave for another day, but the seed has been planted!

Response by Ashton Lewis.