Soured Fruit Beer

The acidity and fruity characteristics in many mixed-fermentation beers make them good candidates for fruit additions. It is not recommended to put fruit into a beer to cover up some major flaw or off character. Fruit can complement a good beer but it will likely not fix problems. Quality fruit is expensive and you'll want to start from a good base if you are going to invest the time and money in good fruit for a beer.

Aging Vessels

In wood or steel (or glass or plastic).

Active fruit fermentation may cause fruit particles to clog the airlock or bung and prevent the vessel from venting pressure. This may cause the airlock to shoot off or worse. The Rare Barrel prevents this problem in vigorously re-fermenting beers by stabling foil over the bung holes of barrels of actively fermenting fruit beer rather than using a bung (~52 minutes in). Raf Soef uses stainless mesh from a tea ball on the bottom of bungs to prevent fruit pieces from clogging the bung or airlock

When using whole fruit, it is typical for the fruit to be carried to and held at the top of the fermenter due to carbonation. Some producers have voiced concern over the fruit sitting for prolonged periods of time in contact with air and prefer to push the fruit cap down periodically (and to ferment in such a vessel as to allow this) (~40 minutes in). If you are fermenting in carboys and feel that you are getting acetic character from the fruit cap being in contact with air you can swirl the carboy periodically. Note that many who have used whole fruit have not noticed any problem with a fruit cap being in contact with air, so you may or may not find that this is a concern for you.

Forms of Fruit

(in progress)

Fruit is available to the brewer in multiple different forms.

• Whole or sliced fresh - Use a CO2-purged keg or minimize headspace in a carboy. Mold and acetic acid bacteria can grow on the skins of floating fruit . Brettanomyces can also produce acetic acid in the presence of O2, and it is possible that this is the source of acetic acid sometimes found in beers with floating fruit rather than acetic acid bacteria. Some brewers like to swirl the fermenter every few days or to keep the alcohol in contact with the fruit, though some others report no ill effects from not swirling the fermenter (and this is impractical in commercial settings). If using a barrel or larger fermenter, you may try using a punch-down technique. If punching down the fruit, purge the headspace of the vessel with CO2 to avoid oxygen exposure to the beer. Allow the fruit to get fully or possibly even over-ripe (not rotten) for best flavor. Whole fruit may take longer to ferment but it also can give the most complexity
• Whole or sliced frozen - Freezing fruit has a few main potential benefits. First, freezing fruit helps to break down cell walls, which may make the fruit easier to access for yeast and bacteria in the beer. Freezing fruit can also knock back the microbes present on the fruit. Note however that freezing does not kill all the microbes on the fruit. Finally, freezing fruit allows the brewer (especially the homebrewer) to take advantage of local and seasonal fruits when they may not have a use ready for those fruits in season. Frozen fruits are also available as IQF, or individually quick frozen fruit. IQF fruit is frozen but each berry is distinct rather than a single frozen mass. This allows for easier handling, helps prevent clumping, makes for easier fitting of fruit into small openings in carboys or barrels, and allows screening and removal of bad looking fruit.
• Pureed fresh - pureeing fresh fruit has the benefit of extracting the fruit flavor faster. It also sinks to the bottom of the fermenter , so the problem of floating whole fruit is avoided. Puree can be difficult to rack the beer off of, and more beer may be lost compared to using whole fruit. Some brewers choose to heat pasteurize freshly made puree.
• Aseptic puree - Same as "Pureed Fresh", but has already been pasteurized. This is usually the case for commercially available puree. We recommend Oregon Specialty Fruit or The Perfect Puree for quality commercial puree.
• Concentrates and extracts - Concentrates can lose aromatics due to the process, and are generally not as recommended. Some manufacturers such as Kings Orchards uses a process that reintroduces the aroma back into the concentrate .
• Juice - Make sure there is no sugar or preservatives added .

Fruit varieties and usage suggestions

Specific notes on select fruit varieties

• Apricots - Apricot pits contain a cyanide precursor, though unpitted apricots, and sometimes exclusively the pits (e.g Cascade Noyaux) are used with success in beer. This would suggest that the amount of cyanide in pits is likely low enough to be ok , and that the pits may add a certain character that some brewers desire. If you are concerned about it, then do not use apricot pits. Cantillon reports limiting the contact time of their lambic with apricots, otherwise the beer becomes too acidic (source-----). This may be due to microbes living on the apricot skins and is likely not due to acids in the apricots themselves.
• Autumn Olive - This is a shrub producing small tart fruits native to Asia and found naturalized in eastern US (though it is considered invasive).
• Black Currants - Finding black currant juice without added sugar can be difficult because of the juice’s high acidity. Keep this in mind when tasting the juice, as the amount of added acidity after refermentation can make the beer unpalatable .
• Blackberries - Adds citric acidity; milder flavor compared to raspberries. Works well mixed with cherries.
• Cherries - Both sweet and sour varieties of cherries are available. Generally sour cherries are used in beer. They are more difficult to find and to source some you may need to look into smaller local farmers or frozen or juice options. Varieties of sour cherries include Schaerbeekse (traditional in lambic), Montmorency, Balaton, Morello and Amarelle. The stones also produce some character and can add to the beer, so you may want to consider leaving the pits in with some or all of the fruit. Cherry pits also have a cyanide precursor (see Apricot, above); however given the success of many brewers using whole cherries in beer for decades or more, the levels of cyanide precursor in cherry stones may not be an issue. If you are concerned about it, then remove the stones from cherries when using whole fruit.
• Cranberries - Consider adding a some raspberries to go with the cranberries for added complexity .
• Fuyu Persimmon - Works well with fruity Brett character.
• Grapes - Wine grapes are preferable for their depth of flavor compared to table grapes. Consider both the influence of the juice of the fruit as well as the potential to pull tannins and flavor/aroma from skins. Some homebrewers have experimented successfully with blending finished wine with beers, and for many brewers you will have much easier access to good wine than good wine grapes . If you are interested in sourcing quality grapes and you live in a wine region, make friends with your local wineries. It will probably be good for you even if grape requests do not bear fruit (see what I did there, that was pretty funny).
• Loquot - Leave out pits.
• Passionfruit - When using whole fruit, use the pulp only.
• Pineapple - Leave the skins out.
• Raspberries - Advice: use a fine-mesh bag for whole fruit or a fine-mesh strainer for puree since seeds/skins may not settle even with extended aging. Frozen products tend to be more consistent than fresh . Raspberries can pair well with both pale and darker sour beers.

Usage Suggestions

"Contact time" in the table below is for mixed fermentations with Brettanomyces. Kettle sours or beers that do not contain live Brett can have a much shorter fruit contact time (generally 1-2 weeks). All contact times are assumed to be applied in secondary, and at the end of aging. Keep in mind that this is just a general guideline for usage amounts. Brewers should consider their base beer's characteristics such as abv, flavor profile, acidity levels, etc. when considering how much fruit to add. It is common for lambic brewers to age much higher fruit to beer ratios and then blend back with unfruited lambic to the desired g/L amount. If you are really trying to nail the perfect fruit amount, applying this sort of technique could be useful (assuming you have suitable beers around to blend back). This will allow you to try different blend ratios to determine the appropriate amount of fruit for your beer and desired outcome.

Fruit can be used for a 2nd steeping and second use of fruit can still provide flavor and color, but in a more subdued way than first use. Both Jester King and the Rare Barrel use fruit more than once, and Jester King reports prefering their second use fruit beers to their first due to more subtlety and balance (~15 minutes in). Other breweries, including Cantillon, The Bruery, and Upright, also report multiple conducting steepings of fruit, at least at one point if not currently.

Don't be afraid to experiment outside of these guidelines.

• Click here and comment on the MTF thread to add your recommendations to this wiki!
• Click here to convert pounds per gallon to grams per liter.

Fruit	Juice	Concentrate	Purée	Dried	Whole	Contact Time	Commercial Examples
Tart Cherry	12-24 fl oz/gal		0.5 lb/gal		1-2.5 lbs/gal	3 weeks juice/6-8 weeks whole	200 g/l (1.67 lbs/gal) Cantillon Kriek, 300 g/l (2.5 lbs/gal) Cantillon Lou Pepe Kriek
Raspberry					1-2.5 lbs/gal	6-8 weeks	200 g/l (1.67 lbs/gal) Cantillon Rose de Gambrinus, 300 g/l (2.5 lbs/gal) Cantillon Lou Pepe Framboise
Apricot			0.75 lbs/gal (~56 minutes in)		1-2.5 lbs/gal	6-8 weeks	300 g/l (2.5 lbs/gal) Cantillon Fou Foune
Nectarine					1-2 lbs/gal	6-8 weeks
Strawberry			0.5-1 lbs/gal		2-3 lbs/gal	6-8 weeks
Blueberry					2-3 lbs/gal	6-8 weeks
Blackberry					0.7-3 lbs/gal	6-8 weeks	350 g/l (2.9 lb/gal) Tilquin Mure
Coconut
Cranberry					1 lb/gal	6-8 weeks
Elderberry			0.5 lbs/gal			6-8 weeks
Plum					2-3 lbs/gal	6-8 weeks	250g/l (2 lbs/gallon) Tilquin Quetsche (contact time of 4 months)
Peach			0.5-2 lb/gal		1-2 lbs/gal	6-8 weeks
Rhubarb			0.5 lb/gal			6-8 weeks
Pear						6-8 weeks
Guava			1-2 lbs/gal			6-8 weeks
Grape (Table)
Grape (Wine)					2-3 lbs/gallon		300 g/l (2.5 lbs/gal) Cantillon St. Lamvinus and Vigneronne
Zante Currant	5-10 fl oz/gal			0.2-0.4 lbs/gal		4-8 months
Black Currant	24-36 fl oz/gal					3 weeks juice/6-8 weeks whole
Passion Fruit					1-1.5 lbs/gal	6-8 weeks
Autumn Olive (Autumn Fruit)			1-1.5 lbs/gal		2 lbs/gal	6-8 weeks
Pomegranate	8-13 fl oz/gal					6-8 weeks
Pineapple					1 pineapple/gal	6-8 weeks
Cantaloupe			0.5 lb/gal			6-8 weeks
Prickly Pear			0.5 lb/gal			6-8 weeks
Apple			0.5 lb/gal			6-8 weeks
Watermelon	64 fl oz/gal					6-8 weeks
Loquat					2 lbs/gal	6-8 weeks
Mango					2 lbs/gal	6-8 weeks
Fuyu Persimmons			2.5 lbs/gal			12 weeks
Olallieberries					3 pounds per gallon (maybe on the higher side but good)	2 months

See Also

External Resources

• Beer and Wine Journal Table of Fruits with water, sugar, and acid percentage.