How to Estimated Final gravity?

Hello how does one find out the final gravity for these recipe’s from morebeer, Northern brewer, etc ?

There is no a fool proof method of calculating FG. The attenuation percentages given by the yeast manufacturers can only be used to compare yeasts not calculate FG. Best you can do is get a range for FG indicating whether the beer will have a dry or sweet finish. Too many variables in brewing a beer whether it be extract, partial mash, or all grain to calculate an exact FG. The only way to determine FG is with sufficient time in the primary for the yeast to finish and accurate SG measurements a few days apart. More than a few days for some yeasts which are slow to finish the last couple of gravity points.

Depends on your yeast and if you are doing extract or AG. AG you can better control your FG than extract. The easiest way to tell if it’s really done is to take a sample, measure the gravity, then take a sample three days later and measure again. If the numbers don’t change, it’s done. For standard gravity OG beers using US-05 I usually finish around 1.012.

Here’s some literature from Beersmith. There really isn’t a short readers digest way to accurately answer your question.

Once we have the grain bill and potentials for each extract or grain in the recipe, the next step is to calculate the “points” for each grain contribution and total them up. This is done simply by multiplying the potential points for each grain by the weight of the grain.

Recall that points are simply the fractional part of the potential – so an extract with a potential of 1.046 is simply 46 points. So for a simple stout with 8 lbs of pale malt (1.036 potential) and 1 lb of roast barley (1.025 potential) would give us:

36 points * 8 lbs = 288 points
25 points * 1 lb = 25 points
Total = 313 points.

The next step is to apply an “efficiency” factor to our process. The potentials given for the grain are the maximum possible amount you could draw from the grains if you crushed them under laboratory conditions with no losses. Real mashing processes and subsequent sparging, boiling and transferring are not ideal – so a typical brewhouse has an efficiency number far less than 100%. The brewhouse efficiency number includes all of the losses in the system into the fermenter including mashing, lautering, boiling, trub loss and transferring the finished wort to fermenter. A typical brewhouse efficiency number for a home system is 70-75%. In this case we’ll use 72%

313 points * 72% efficiency = 225.4 points

Now we just divide by the “into fermenter” volume which in this case is 5 gallons:

225 points / 5 gallons = 44.8 points/gal

And that is the original gravity estimate if we convert it back to specific gravity – 44.8 points gives us an OG of approximately 1.045

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And if you are wondering how NB and MoreBeer figure these numbers out…they do what everyone else does and uses brewing software which calculates the stuff for you.

And don’t fergit the variables’ that different yeast bring to the party to, low attenuation, high attenuation…. Sneezles61

Yeast health, pitch rate, temps…

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Yes the art of brewing beer. I try to stick to kveik yeast. Now. Even with out calculating. And have done about. 25 batches.with kviek yeast . I know. The fg. Ends up around. 1.012 to 1.010. Aa yes. Should have tomorow. 12 vials. New kveik in my house

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