Home Brewing Forums
Harvesting and re-pitching yeast
Sun, 04/26/2009 - 12:39
I have saved yeast a couple of times with mixed results. I basically follow instructions from the Joy of Home Brewing; bottling some slurry from the bottom of the last batch, into sterile wort with plenty of headspace, and then capping.
I've had poor results twice doing this. The first yeast was a NW Ale yeast (like American Ale yeast but more esters). The second time was with some saved 1275 Thames Valley Ale Yeast.
The Problem
The main problem each time was a strong banana (at first with the NW Ale) and then strong and lasting medicinal (band-aid) taste. Both batches remained "band-aid beer" after aging in bottles.
The ales were mostly drinkable, but not quite right.
I assume the problem is either (1) the yeast is not "happy" or (2) some other yeast got in and made it funky.
From the symptoms, (1) seems more likely.
The Cause?
I'm guessing problem is that the yeast was stored long enough in the fridge (say, 3 months), that it needs to work in a starter before being pitched into the full wort. Other ideas are that I pitched downward in gravity. Not sure how much that would matter if the second batch for that yeast was slightly lower gravity.
How do I prevent band-aid beer, besides just buying new yeast every time.
Thu, 11/05/2009 - 18:10
#2
Great tips, thanks.
Hi. Thanks for the great tips on making starters: they will definitely come in handy. We are working on getting some nice Erlenmeyer flasks in our shop for this very purpose.
Since our original posting, we did keep having this wild yeast flavor. It was like our beers were all trying to be Belgian. It turned out that our main problem was some old worn plastic equipment (a primary fermenting bucket with a hard-to-clean spigot or maybe a hose or two). A customer recommended we change out all our plastic gear. We got a new bucket and racking cane and our next batch of beer was extremely clean (we posted the recipe: Fresh Prince Porter). Having a fresh starter of course would also help our yeast of choice win the battle against whatever wild yeast was stuck in our gear. (It certainly didn't taste like any of the bacterium but more like a wild yeast.)
Mon, 12/14/2009 - 01:14
#3
Portland has a ton of
Portland has a ton of cloramines in the water. this tends to be the culprit with band aid off flavors. I would reccomend using campden tablets in your brewing water
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I think you're on to something with your ideas about the causes. First off, are you bringing the stored yeast up to room temp before pitching? I find that taking the jar out and leaving it on the kitchen counter the day before I am going to brew does wonders in waking it up. Here's the process I follow, taken from Jamil Zainasheff's directions at http://www.mrmalty.com/starter_faq.htm
Remove the jar from the fridge the day before brewing. Take off the lid and cover it with a sanitized piece of aluminum foil, so that it can come up to room temperature. Prepare an unhopped 1.040 wort (easiest way: 50 grams of DME in 500mL of water, boiled for 15 min), and let it cool. When the starter wort is cooled to ~70, pour off most of the old beer from the yeast cake jar, then pour the cooled starter wort into the jar. Swirl the jar to suspend all of the yeast cake, then pour the entire contents into a freshly-sanitized jar (or, even better, a 1-liter Erlenmeyer Flask). Put a sanitized piece of aluminum foil over the top of the flask/jar, and give it a shake every hour or so until you pitch it. The oxygen that you dissolve during the shaking process gives the yeast the chance to reproduce, and you don't have to worry too much about infection because bacteria can't crawl. Pitch this starter into your new wort when you're ready - shake it up and pour it all in - the optimal pitching time is 12-18 hours after you've begun the starter process, when the yeast is healthiest and ready to go to work.