If you’ve ever had a rushed brewday, then you might have considered an overnight mash. You might also have considered one if you’re a disorganised bastard who tries to do too many things before ultimately realising that you’ve neither the time nor the energy to carry out an all grain brew, nip to the allotment to do a bit of casual muck-spreading, collect a whole pig from the butcher, watch football and change the brake pads on a truck, and get everything finished and cleaned up before the other half gets home from work.
Well, I’ve considered an overnight mash many times, but I kept on getting the fear. This was despite many people regularly doing them. Each time I built up my confidence, some big head know-it-all home brewer would caution about oxidation, incomplete enzymic activity, low efficiency and even genital warts. It was just too risky, a bit like feeling up Crazy Dave’s wife when he nips to the bog!
Then it happened. I considered the total value of a screwed-up brewday – about £10 – and decided to shoot the moon. My mash tun is a converted 45 litre Igloo Ice Cube. I was a little concerned because I’d read a few comments that intimated that the lid – which uses the typical post-fixings – would simply let too much heat out, and unless I purchased an over-the-top tun with hinges and a locking lid and enough room for twenty elephant bollocks, I would be looking at five gallons of tepid piss-water come the morning. Still, I had no choice, so I decided to seek out some insulation.
On the Friday day before the Friday night mash, it was pissing down. Those of you who live the South of England will understand; if you don’t, think Noah if he’d ended up really deep in the shit. I phoned my other half and after some casual chat I asked her if she’d pop to Millets for me. She asked why.
‘Why?’ she asked. See! I told you so!
‘I need a survival blanket. It’s a thin silver one, I think it’s a Highlander blanket, they’re two quid.’
‘Why do you want that?’ She seemingly wasn’t too keen to get drenched.
‘I need it for a thing, tonight. Also, do you know where that Arctic sleeping bag is?’
Now, I don’t know whether she thought I’d suddenly taken up mountaineering, but to be honest, I’ve done stupider things in the past, so she got me my foil blanket. I was set! I decided to make a Dirty Chimp Oatmeal Stout.
By 10pm, she started to wonder why my new mountaineering hobby looked more like me sitting on the sofa, watching TV and drinking beer. I explained that I needed the blanket to carry out an overnight mash. She said something that rhymed with duck cough, and went to bed. I finished my beer and headed into the kitchen to set up.
Everything proceeded as per a typical brewday, only it was 10.30pm instead of 9am. In went the grain, in went the strike water, and the mash temperature was measured at 68 degrees C. I wrapped the mash tun in the survival blanket, then pulled the sleeping bag over the top. That was that, and after a few more beers I went to bed.
Did I sleep well? Did I buggery. I tossed and turned, moaned and groaned, and at one point I nearly wept. What was happening down there? Was the temperature plummeting? Was the beer dead? What had I done? I nearly got up to and start sparging, but I fought the urge. I tried to think about Lorraine Kelly, straddling me in that latex catsuit she wears on a Friday night, but it didn’t work. She leaned forward, her lips pouting, and whispered, ‘The mash temperature’s falling like an anvil through the plate glass roof of your soul.’
It was a terrible night, and at 6.30am I could take no more. I got up, made a very strong coffee, and prepared for the worst. I pulled off the sleeping bag, and it felt warm. The survival blanket felt warm too. Maybe all was not lost. Then I lifted the Igloo lid and stuck in the thermometer.
62 degrees C. Shit the bed. It had lost 6 degrees in eight hours. I drained it, off, sparged, and was boiling by 8am. At 11.30am I was cleaned down and off out to the allotment. Happy days!
Did anything go wrong? Of course it did! Somehow I managed to screw up the strike water and sparge water amounts. The boiler did look much fuller than normal, to the point that I drew some off and boiled it in a separate pan. I was aiming for 5 gallons at 1.062, but ended up with 6 gallons at 1.050.
As a result I’ll be bottling four gallons of Dirty Chimp, and two gallons of Nutty Chimp. The latter is just Dirty Chimp, but with the addition of some vodka which has had hazelnuts steeping in it for two months!
Overnight mashing; it’s like sleeping, but you’re making beer!