Wednesday, 8 April 2009

Back to brewing

I spent the day making beer at a commercial brewery on Monday. I met up with a friend from Heriot-Watt who now works there and helped him make a strong mild. Both the friend and the brewery are a little publicity shy so I won't be naming any names or showing any pictures. 

Here's some stunt wort standing in for the actual wort

The brewery was less than a tenth of the size of the one I used to work at but the processes were similar.  The details were different though and being a beer nerd I was very interested to see these, which I will now go on about at inordinate length:

Mashing in
They hadn't quite got a grist case sorted out from which they could mix in the grains with the mashing liquor, so the set up was more like my home brewing than when I brewed professionally. The mash tun was filled with hot liquor and the grains tipped in whilst stirring with a paddle. They had quite a high liqour to grist ratio so stirring wasn't as hard as it could have been. Still, I'm sure they'll be pleased when they get their latest building project is finished. The grist itself was quite complex, being made up of six or seven different grains. 

This was much more involved than I was used to. Instead of only pouring back the first three jugs of sweet wort they connected up a pump for a full 15 minutes of recirculation. Personally I'm very much in favour of having clear wort, though I did wonder if the recirculation time could be cut down.

The boil
Their current copper is gas fired whereas I was used to was steam heated. This did cause a slight problem when one of us managed to kick the gas supply lever and turn the burner off. Fortunately the interlude was only brief so no harm done. I have seen it claimed that direct fired coppers cause slight caramelisation of the wort but it didn't seem to be the case here.

Irish moss was added in the last 15 minutes, rather than protafloc tablets, to aid hot break formation and prevent hazes. I was slightly surprised at this as I find adding protofloc tablets to the wort one of life's small pleasures. They don't sell protfloc tablets at my local homebrew shop so I've been having to make do with Irish moss but I'd expected commercial brewers to have protfloc as standard. 

Late hops
This brewery took such care with their end of boil hops that they waited until the wort had had twenty minutes off the heat before adding them. This will help ensure that hop aroma loss due to volatile oils evaporating is minimised.  

The hop back
This brewery had one. The one I worked at didn't. Didn't make much difference, thought some breweries add aroma hops to the hop back. I heard from my mate he'd been to one 16-20 barrel brewery that only adds one kilogram of hops to the copper but adds ten to the hop back.  

The Fermentation Vessels
This brewery had closed FVs, which I hadn't worked with since Heriot-Watt. Obviously this meant the yeast couldn't be skimmed but it was a bottom fermenting strain anyway. It has been said open fermenters give better flavoured beers but I know of some cracking beers that come from breweries with closed fermenters I'm not convinced. The risk of infection to the beer must also be greatly reduced but not having the FVs open to the atmosphere.

The Conditioning Tanks
The beer here was conditioned under slight pressure. Not sure why this was, I should have asked really. Does this mean I'm failing as a beer nerd?

I didn't see any racking or bottling but my friend made it clear that both were very labour intensive so maybe I had a lucky escape. The head brewer was very particular in ensuring that everything was done to perfection and this did make for a long brewing day. 


  1. Could the conditioning tank under slight pressure to aid in packaging? ie transfering to casks or bottles?

  2. I'd guess it is to keep oxygen out before packaging and prevent staling, so I'd agree with Tim here.

  3. Hmmmm...postive pressure in the tank would ensure no air get in but when I racked beer into casks the conditioning tank was opened to the atmosphere and the beer flowed due to gravity. I'll make enquiries.