Emergency - raspberry wheat beer threatening to take over the cellar!

[BlackRegent]

Hi everyone,

I hope I can call on your collective wisdom and hopefully receive some comfort.

I am on the third day of brewing an all grain raspberry wheat beer (p.210 of HBB) which I started on Friday evening. I am using Wyeast 1010 American Wheat and fermenting in a 6 gallon fermonster (rather than my usual 30 litre buckets) with bung and airlock as I wanted to see the fermentation of the raspberries first hand.

The initial spike in fermentation was pretty vigorous (some overflow but nothing too bad) and settled down quickly.

I have added the raspberries today (frozen then defrosted up to room temp) today. Adding the raspberries took the contents within a few inches of the top which made me slightly nervous. Literally within 30-60 mins of adding the raspberries, the fermentation has gone beserk. I've cleaned up and added a blow off tube into a 2L coke bottle, but the problem is the bits of raspberry keep blocking the outlet and tube causing the bung to be blown out.

I have given up trying to put the bung back in and have just left it with the bung hole open with some towels wrapped around the bottom to mop up the worst of it. It is now bubbling away merrily, but is obviously exposed at the top and pushing out foam and some of the raspberries (although the recipe is so raspberry heavy that there will probably be plenty left).

So 3 questions: am I OK to leave the bung out until the fermentation has settled down again? I would have thought the risk of infection was minimal given all the carbon dioxide being forced out - am I right to think that? Would anyone decant into a larger fermenter or is that a really bad idea at this stage? Does anyone have any tips to stop the bits of raspberry from blocking the airlock and tube?

Thanks in advance to everyone.

 

[cushyno]

I'd sanitise a piece of aluminium foil and crimp it over the top. It'll let the co2 out, prevent any bugs getting in but also let the overflowing yeast out without letting raspberries out. You may need to change it periodically and mop up the mess until fermentation subsides. Though if it's that vigorous nothing will be getting in to infect it if there's that much yeast and liquid being pushed out.

 

[alsch890]

Got any photos?

 

[BlackRegent]

Got any photos?

I didn't take any unfortunately. At worst it was like a school science experiment - thick pink foam oozing out the top with bits of raspberry in it. I left it overnight with the bunghole exposed. It had a thick cap of foam over the hole so I figured that would do the job of protecting the contents along with the positive pressure and CO2. It's settled down again now. Still lots of foam but it doesn't seem to be expanding and I've cleaned up what I needed to. Smells fine so I'm optimistic no harm was done. I think the basic problem was using a FV that was too small for a vigorous ferment!