Estimating The Fg Of Fresh Wort Kits.

[mynameisrodney]

Hey guys, I'm doing a Celtic Red Ale FWK at the moment. Kit + 4L of water to 19L 1.042. How do you estimate where this will finish without actually knowing the ingredients?

Cheers
Chris


EDIT: sorry, forgot to add I'm using S04 yeast

 

[quantocks]

Brewers Selection Celtic Red Ale - S.G. 1.037 F.G. 1.006 Yeast: WhiteLabs WLP004 Irish Ale - Good result
Brewers Selection Lager - S.G. 1.040 F.G. 1.013 Yeast: WhiteLabs WLP838 Southern German Lager - Fair to Good result, brewed a bit warm
Brewers Selection Celtic Red Ale - S.G. 1.037 F.G. 1.006 Yeast: WhiteLabs WLP004 - Good result
EzyBrew American Pale Ale - S.G. 1.038 F.G. 1.020 Yeast US-05 - Very Low Alcohol, but good tasting beer. Yeast was good. Active starter.
Brewers Selection Amarillo Ale - S.G. 1.048 F.G. 1.011 Yeast US-05 This is very good beer


http://www.aussiehomebrewer.com/forum/inde...showtopic=20827

 

[buttersd70]

Chris

There are so many things that come into play with projecting FG, so all you can do is make a best guess based on the only variable that you are likely to know; the yeast. And in the case of FWK, the brewer would also have designed it with a style in mind (in this case, Red Ale), and would have designed the grist and the mash schedule to suit. By looking at the BJCP style guides, it will give a guide to the OG and FG expected. (bear in mind that BJCP is a guide, not gospel, so the beer may have been designed slightly differently....but its a starting point to get a general idea on where it's going)

Fermentis advertise attenuation on their yeasts as low, medium or high, with no specific numbers...but a quick search on google showed several retailers advertising it as 70-75% (although can't vouch for the accuracy of this)....so for OG of 1042, you would be looking at somewhere in the region of 1012...which makes sense, given that the style should be 1010-1014 FG....

So, anywhere in the 1010 to 1014 region. Having said that, it may well be quite different....it's a projection only, and as I'm sure you're aware should not be taken as a sign that fermentation has finished...only consistant gravity readings will do that.

 

[mynameisrodney]

Ok thanks guys.

Also, I have never used a FWK or S04 yeast before, but this hit 1.012 about 44 hours after pitching the yeast. The only reason i checked it so early was because the airlock went from going nuts to nothing in the space of a few hours, and i couldn't see how a leak would have developed in that time. It tastes/looks ok, but that is a damn lot faster than any brew I have done before. Do FWKs ferment quicker than extract? Could it have been an extremely healthy pack of yeast? Is there a type of infection that can cause it to drop this rapidly?

Cheers
Chris

 

[Ross]

Chris,

A healthy yeast pitched at the right quantity should generally see an ale finished in 3 to 4 days, so looks like all is going pretty well, though a tad fast.
I'd suspect you have fermented this out a bit on the warm side though, what temp did you ferment at?

Cheers Ross

 

[mynameisrodney]

19C in a fridge with fridgemate. Sorry, I meant to put that in the last post. The yeast did look quite healthy when I rehydrated it, but it still seemed way too fast and i was a bit unsure.

Cheers
Chris

 

[Fermented]

It's a bit quick but it's plausible.

What's the most recent SG reading?

Cheers - Fermented.

 

[mynameisrodney]

1.011 after 84 hours. I'm going to leave it another week or so anyway.

Cheers
Chris