My 4th Zymatic brew was a reworking of one of the best beers I ever made and one of my early beers – Hops of Mass Destructions – which was a Ruination IIPA clone. “Baby Ruin,” I named it – being a more sessionable version of HOMD/Ruination – and by geeze did it live up to its name.


It was almost a completely successful brew – but then in the last minute of the chill cycle the Zymatic foam trap exploded shooting the middle spindle into the air (narrowly missing my face) and hot wort onto the ceiling.

Of my brand new house.

The photo above is of the ceiling. The photo below is of the foam trap minus the flying spindle.


I, of course, reached out to Picobrew.

The only thing that I can think of is something was preventing it from venting.

Make sure that you aren’t running a prolonged chill cycle, because of the physical properties of the sugars at lower temps you’ll start getting a lot of foaming.
Something had to have been causing the spindle to stick to the disc and sealing it off there’s no way that enough force should have built up for this to happen, but the keg seal should have popped before it was able to launch it far enough to hit the ceiling.
Unless you’re brewing with dynamite, are you brewing with dynamite?

And:

In my 3 years with the company and hundreds of brews on a Zymatic I’ve never seen, nor even heard about this happening.

So I’m unique. Sometimes it’s good to be unique. Other times. I’d rather pass.

I have a query back to Pico on suggestions to prevent this in the future, but haven’t had a reply back for the last 4 days (which does include the weekend). While their reply is reasonable, I’m amazed such force could build up. The keg seals I have (which the foam trap goes into, like an airlock) are an extremely tight fit so definitely won’t pop to relieve pressure.

I was running a 30m whirlpool through cage and keg hops (the hops being in a 300 micron container) before the ice bath chill – but then plenty of others do that too, so it shouldn’t be an issue.

I’ve come to the conclusion that the chill cycle through the machine is a bad idea – it just creates too much foam. In this brew I actually reduced the duration of the chill cycle by setting target to 30C rather than 19C (the default). So I need to work out what I’m going to do about that. Overnight chill isn’t really an option for an IPA.

In the meantime:

1. Use tap water straight from the tap rather than the water filter to see whether that helps with foam. Apparently the wrong type of water (which is water without minerals) can cause the Z to foam. Our water filter is so weak and needs replacing that I doubt it’s having an affect anyway but worth a try, as is looking more into water chemistry.

2. Add a few drops antifoam to the keg – though I did add to the mash in this case so I don’t see that will help.

3. Check the spindle every 10 minutes during whirlpool and chill – you have to be at the machine anyway during that timeout.

4. Change the way I do whirlpooling. One option would be to do a smaller circulate through the hop cages and then a hop stand with hops in the keg. This would reduce circulation time and may give foam time to settle.

The good news is that the brew seems to be bubbling along nicely and a midweek sample was very promising. I’m monitoring its progress on one of my Tilt Bluetooth hydrometers which makes monitoring the whole fermentation process very addicting indeed!

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