How long should I leave fruit in my beer?

[Calder]

I have a Porter that I moved onto fruit yeaterday. Any advice on how long I should leave it?

It is a 1.055 basic Porter, lots of Chocolate malt, but no Black/Roast/etc. 3 weeks in primary, racked onto fruit yesterday at 1.012.

Split into 3x3 gallon fermenters, 2 gallons of the base ale in each. I added the following to each one:

- 3 lbs mashed raspberries, made up to 0.5 gallon. Plan is to add 2 ozs of whole coffee beans 7 days before bottling.

- 3 lbs mashed raspberries + 4 ozs cocoa powder made up to 0.5 gallons.

- 4.5 lbs Cherries (including stones) + 4 ozs cocoa powder made up to 0.5 gallons.

I have 2.5 gallons in each fermenter. All 3 have new activity.

My previous usse of fruit has been in sours where it is left in there for several months. I'm thinking 2 to 3 weeks for these.

- Is 2 to 3 weeks fine; should it be longer or shorter?
- What risks or benefits do I have leaving it 3 weeks vs 2 weeks?

 

[Talgrath]

I'd say two weeks is probably sufficient, but if you want to be really sure, three weeks. As far as risks, pretty much the only risk is the (very slight) potential that you may have infected the beer by adding the fruit, technically you could leave it there as long as you like.

 

[madscientist451]

The only way to tell is to pull samples and taste it. Since your base beer is a Porter, it might take a while for the fruit character to come though. I've put beer on fruit and often the yeast will kick off again, you then loose some of the fruit flavor and aroma as the C02 blows off. Also, when you get the flavor profile you are looking for, you can then add more beer to the same fruit, the second batch will have a different maybe even better fruit character than the first, since the sugar from the fruit is gone and the yeast won't kick off again. You can experiment with blending the first and second batches for a more complex version. So if you can, brew another batch now and put it through primary fermentation and have it ready to add when the first batch is done.

 

[Teromous]

After racking off of the yeast cake in the primary I would personally let it sit there for a month to extract the most flavor and get my money's worth. I can't tell you that you will notice a difference between 2 and 3 weeks because everyone's palate is different, fruit is fickle, and base beers can have different strengths (insert obvious disclaimer). If you want to keep dipping a wine thief in there to draw off samples to determine the optimum flavor (for fun or for science) then you can but again I would personally let it just sit there undisturbed for a month. As for the coffee I don't have a lot of experience there so take my advice with a grain of salt, but I have seen a number of recommendations to not use whole coffee beans. One recommendation from Zymurgy Magazine is to cold brew the coffee before-hand and add an ounce or two of the finished coffee to the fermenter. Hopefully an avid user of coffee can step in and give you their advice.