mozza wrote:I've got a load of bananas in the freezer, could I peel and chop them and put them in the boiler for the last 20 minutes? Or is that silly

I dunno. How does
Wells Banana Bread Beer do it?
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WEIRD ANSWER WARNING
I can't think of any beer recipes containing actual banana, but there's no intrinsic reason
not to do it. Here in the US, paw paws (a native fruit which has a taste somewhat comparable to bananas) have been used in "farmhouse brews" throughout history. Here are a couple recipes I found on the internet, feel free to Google "paw paw beer recipe" for more. These sound similar to what you're proposing, but the fruit is added to secondary fermentor, similar to a fruit lambic process...
Jeanna's Paw Paw Pale Ale
5 Gal Extract w/ Steeped grains.
I lose 2 gal/hr from my keggle so I boil 7 gal. You can adjust for your system.
6# light DME
1# Crystal 60L
1# White Wheat
3/4 oz Cascade (6.3 AA)(60 min)
1/2 oz Glacier (5.8 AA) (20 min)
Irish Moss
WLP002 English Ale
7# Paw Paw pulp; Thoroughly freeze to kill off any wild yeast.
Steep grains @153 for 45 in 5 Gal. Add DME and 2 gal of water bring to boil and add Cascades. Boil 60 adding Glaciers the last 20; Irish Moss the last 15.
Cooled to 75 F and pitched straight from vial.
Fermented in Primary 2 weeks. Racked to Secondary and added Paw Paw. Racked to another secondary after 6 days.
Left it in there for another 10 days to settle out. Bottled conditioned for 2 weeks.
It was a little rich so I think I'll use less fruit next time and possibly tweak the Hop schedule. I think it would mellow well with age but my friends and family are thirsty.LOL.
OG: 1.059
FG: 1.014
ABV: 5.9 = 131 x (1.059 - 1.014)
I think I'll use 3.5# of Paw Paw next time.
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KVP Paw Paw American Amber Ale
Size: 5.0 gal
Efficiency: 75.0%
Attenuation: 75.0%
Calories: 170.55 kcal per 12.0 fl oz
Original Gravity: 1.051 (1.045 - 1.060) hit 1.048
Terminal Gravity: 1.013 (1.010 - 1.015) hit 1.013
Color: 14.45 (10.0 - 17.0)
Alcohol: 5.04% (4.5% - 6.2%) hit 4.54
Bitterness: 35.0 (25.0 - 40.0)
Ingredients:
7.5 lb American 2-row
1.5 lb Crystal 60
1.0 lb White Wheat Malt
1.0 oz Cascade (6%) - added during boil, boiled 60.0 min
1.0 oz Glacier (6%) - added during boil, boiled 20.0 min
1.0 ea White Labs WLP002 English Ale (my notes show I used WLP005)
3.81 lb Paw Paw puree - added dry to secondary fermenter