I've had a bag of grain ready for brewing for several months, and a smack pack of yeast in the fridge for over a year. Yesterday I decided to put both to work to see if good quality beer can result in such old ingredients.
First off, I had a mix of 95% Simpsons Maris Otter, 5% Simpsons Dark Crystal which was supposed to go into a Fullers ESB type beer. The yeast is a WYeast 1026PC cask ale, manufactured June 2013!
Chewing on the grains I discovered that they still had plenty of crunch with no discernible musty notes. The yeast I smacked and waited about 8 hours until I could see that the pack was beginning to swell. At this point I decided to bank this yeast in glycol stocks. I made a quick post on aussiehomebrewer.com about this.
I was still not too sure about the actual viability of the yeast, so the wort was no-chilled to ensure that it can wait until I either propogate or buy some healthy yeast.
Given the yeast issues, I dumped about 800g of my grains to come up with the following grain bill:
4.67Kg Simpsons Maris Otter
0.25Kg Simpsons Dark Crystal
then very loosely based on a Can You Brew It Fuller's London Pride recipe, the hop bill is as follows:
12g Northdown @60mins
22g East Kent Goldings @60mins
18g Northdown @ 0mins
25g East Kent Goldings @ 0mins
I took 250ml, 700ml and 2L wort samples for stepped starters, and no chilled the rest. The mash was recirculated at 65.5 for 50mins, mash out at 78 for 10. I got pretty good efficiency here - OG of 1.051 for 75%, a little more than I expected.
My yeast adventures began with pitching the 100ml remaining in the 18 month old WYeast pack into 250ml of wort. I watched this for two days but there was no discernible activity. Despite this there was a slight drop in gravity so I decided to pitch this to the 700ml wort flask. After another day or so I had lots of activity in this flask, but this failed to pass the sniff inspection (never mind the taste inspection). It had serious medicinal/phenolic aromas. Either the yeast has mutated severely, or most likely I've got some Brett or something in there. I will try to streak out a few colonies from the frozen stocks to see what I come up with, but this won't be done in time to ferment this batch.
The solution is a fresh smack pack of WY1968 london esb ale yeast. This will be pitched to my 2L starter tonight, followed by pitching to the main batch tomorrow. Fermentation will be at 18C rising to 20 towards the end.
Had I known for sure that the WY1026 was a no-go, I would have mashed a little lower to achieve better attenuation. However, I have just gotten myself a little pure oxygen aeration kit, so 60secs of Oxygen may help to boost yeast health and numbers and achieve a dryer finish. Updates on this fermentation will follow.
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