high gravity - wrong yeast?

[Karle]

I was wondering whether anyone out there could help me...

I brewed a high gravity Belgian ale this weekend (OG 1070) but since I could not find a special Begian Ale yeast in the two homebrew shops I went to, I took a wheat beer yeast. I made a starter (one dry yeast, approx half a litre of water, gravity 1030, at 20 degrees C, left it for 7 hours) and after pitching it in the wort it's showing vigorous activity.

I know that the yeast isn't perfect - could it be that it will be killed by the developing high alcohol levels and not finish the fermentation. Should I pitch a second round of yeast?

Has anyone experience with this?

[Kempicus]

1070 ain't that high, i've never had a problem at that gravity

[JoKing]

Your yeast will be fine. It may underattenuate though as I dont't think 1 packet of yeast is enough to attenuate that type of OG. It would have been a good idea to have pitched 2 packets to ensure a healthy fermrntation. What you will probably get is a highly estery brew because of the extra work the yeast has to do in attenuating your fermentables. I'm assuming you have used wb-06 in this - and you will find that it will pump out plenty of banana - whach may or may not be what you want for your beer.

I'd recommend that (now you have noticed a high Krausen) you ferment the brew out between 17 - 19 degrees C as this strain is known to pump out bulk amounts of sulphur when it gets too warm and stressed.

Good Brewing.

[Karle]

Thanks for this, Joking. Do you think it would be a good idea to add more yeast when the current fermentation has slowed down? Or shall I just leave it as it is? It's at 19 degrees, so I hope it's gonna be fine in that respect.

[JoKing]

You wont need to add more later - it really only counts at the start. The yeast basically takes stock of the situation at hand when it is pitched into the wort. Therefore if you put more of the same strain into an already fermenting brew, it takes on the activity of the fermenting yeast. Unless you can get a new starter of new yeast into high Krausen - then pitch that into your fermenting batch, you'll be wasting your money.

Your current yeast has already grown into a colony large enough to attenuate your wort - the problem with this is that it had to work extra hard to build up the necessary numbers to do so. It probably wont adversly affect the flavour of your beer - because you want a certain amount of fruity flavour in your batch anyway. My guess is, is that will probably under attenuate: no big deal.

You'd be best to leave it at 17-19 until it show visual signs of easing fermentation. Then warm it up to about 22 - 25 degrees for a few days until th FG has become apparent, then do what you normally do when you get to the end of your fermentations (i.e secondary, or bottle).

Cheers.

[Karle]

awesome, thanks!