Share your experiences of using brewing yeast.
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AngloScot
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by AngloScot » Fri Jul 13, 2007 9:47 am
Does anyone have any experience using Wyeast 3944 (Belgian Wit).
I've used this in a Wit that I brewed on Sunday and the fermentation has been very slow. The gravity is currently sitting at 1.026 after starting at 1.043. What seems odd is that there is still a big yeasty head in the fermenter but the airlock activity has dropped down to about one bubble every 45 seconds. To be honest the fermentation never really seemed to take off with a bang (I'm used to using Safale S-04!

) and I can't see this brew getting anywhere near a decent final gravity. I did create a starter for this brew but it just seems so slow. The fermentation temp is a good 21C as well.
Any ideas? Rouse the yeast a bit? Try and get hold of some more wheat yeast?
Cheers!
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steve_flack
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by steve_flack » Fri Jul 13, 2007 10:30 am
What was the recipe/procedure? What did you mash at? It might not be the yeast.
The only real way to find out is to take a small sample of the wort when you put it in the fermenter in a separate container, add a good wodge of yeast to it and stick it somewhere warm (airing cupboard will do). The idea is to force the yeast to ferment fast and quickly. You will then know how far the bulk batch (going slower at a proper temp) will ferment to eventually.
To be honest I don't do it but it's the only real way to know what to expect.
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AngloScot
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by AngloScot » Fri Jul 13, 2007 10:43 am
Recipe was for 5 US gallons (i.e. 18.9litres):
1.8kg Pale malt
1.8kg Wheat malt
0.25kg Whole wheat flour
Saaz hops for bittering and aroma
Coriander seeds and ground ginger for flavour/aroma
1 Whirlfloc tablet in last 15 minutes too.
This was the first time I'd tried my coolbox mash tun and I screwed up the temp initially. Initial mash temp was in the high 50s! I quickly rectified this and the mash proceeded at ~65C for about an hour and 15mins. I batch sparged/remashed 4 times (using ~77C water) to get the required volume of wort. My original gravity was quite a bit lower than expected 1.043 rather than 1.048 which I put down to my inexperience at mashing as well as my water probably needing to be treated a bit more to get proper mash pH.
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steve_flack
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by steve_flack » Fri Jul 13, 2007 11:15 am
You look a bit short of ingredients to me to get the gravity you were aiming for. I've not run the numbers through a calculator but it just looks a bit low....
I don't think your mash temp cock up is the problem as wheat beers are often step mashed anyway. So long as your thermometer is accurate you should have been fine.
Did you aerate the wort well before you pitched?
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AngloScot
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by AngloScot » Fri Jul 13, 2007 11:32 am
Did my usual aeration routine.... letting the wort run from the boiler tap from a height into the fermenter, put the lid on the bin and give it a quick shake. This is typically good enough for S-04 but I've found that yeast to be pretty much bombproof.
I've had some problems with liquid yeasts before. Could it be that I needed to step up the starter a few times? Basically I split the smacked pack into two cooled and aerated bottles of ~300ml wort. Both were left for 48 hours before pitching and showed activity (froth on top and sediment at the bottom). I did notice that although the smack pack had swelled up a bit it wasn't "tight as a drum". Even after 2 days.
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steve_flack
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by steve_flack » Fri Jul 13, 2007 11:38 am
How long was the lag after you pitched into the full size wort?
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AngloScot
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by AngloScot » Fri Jul 13, 2007 11:56 am
Lag time was less than 24 hours. The fermentation just seems really slow. At best the airlock was bubbling every 15 seconds or so but this has tailed off to about 50 seconds now.
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steve_flack
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by steve_flack » Fri Jul 13, 2007 12:26 pm
I dunno what the problem is then.
You could try rousing or chucking in some T58 dried yeast. That's pretty wit like.
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AngloScot
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by AngloScot » Fri Jul 13, 2007 1:05 pm
OK, I'll give the rousing a whirl and if that fails hit it with a bit more yeast.
Thanks!
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mysterio
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by mysterio » Fri Jul 13, 2007 1:07 pm
Assuming the yeast is the same as the White Labs equivalent, I find the fermentation speed drops dramatically when the temperature gets to 18C or lower. The first time I used the yeast, fermentation took a good 14 days (longer than is good, but the beer turned out fine). The second generation fermented quicker.
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AngloScot
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by AngloScot » Mon Jul 16, 2007 9:52 am
Just to update this thread. I tried stirring up the sediment on the bottom of the fermenter on Friday night. This got the fermentation going a bit (airlock started bubbling every 20 seconds or so rather than at 50 second intervals).
After reading up about Belgian ale yeasts (especially ethanol tolerant ones) it would appear that they quite often throw a lot of yeast up and out of the fermenter leaving little yeast remaining in the wort to finish the job. My reference recommended stirring the yeasty head back into the fermenter. I gave this a try last night as the fermentation was showing signs of slowing down again. I gently stirred in the foam and scraped most of the yeast deposit at the top of the fermenter back down into the wort. By this morning the fermentation had gone wild - the airlock was nearly blown out.
I'm pretty hopeful that this fermentation should now complete.

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AngloScot
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by AngloScot » Tue Jul 17, 2007 9:30 am
Yep. The gravity is now down to 1.010.
Mild panic over!
