Since I dont have a hydrometer....

[cdew4545]

Since I don't have a hydrometer at this point, is there a way to guess at the alcohol content as per the ingredients of a recipe? In other words, is there a simple relationship between amount of DME and alcohol content assuming everything is fermented that can be? (i.e. Does 1 pound of DME = 1% ABV) I'm looking at this from the point of being able to design a beer. Say someone wanted a lower 3% pale ale versus a high 6% pale ale. With the same recipe, how would you alter the sugar (this question is strictly fermentables, not about hop bitterness). Also, what if someone wanted a 6% pale ale, but wanted a cut back on the body, would you substitue in corn sugar or some other different sugar to achieve this? I know this post is loaded with questions, but an ideal answer for me would be something like this...

1 lb barley DME = +.5 %ABV
1 lb wheat DME = +.4 %ABV
1 lb corn sugar = +.75%ABV

I know this probably isnt easily answered, but any input would be appreciated. I'm talking all in 5 gallon batches here by the way and assuming adjuncts dont add that many fermentables (correct me if this is wrong as well)

Thanks a ton

 

[Brewsmith]

It all has to do with two things, Points per Pound per Gallon, or PPG and Yeast Attenuation, usually as a percentage.

One pound of DME in one gallon of water will give a gravity of 1.046 or 46 PPG. Five pounds in five gallons still gives 46 ppg, or put a different way, in five gallons each pound of DME adds 9.2 gravity points.

LME gives 36 ppg, or 7.2 points per pound in a 5 gal batch. It is less because part of the weight is water.

Now here is where attenuation comes in. Say you start with a wort at 1.055 (roughly 6 lb. of DME). If your yeast says for example that it has an attenuation of 75%, you can expect the final gravity to be the remaining 25% of 1.055, or 1.014. Now just look up a table, or brewing calculator, for alcohol content to find that this gives a 5.4% ABV.

Here's the monkeywrench: Corn Sugar is 100% fermentable. It also gives 46 ppg, but all of it will get fermented. Back to example:

Add 1 lb. of corn sugar to our brew and the gravity increases to 1.064. The yeast will consume all of the corn sugar and 75% of the DME, still giving the 1.014 final gravity, instead of 1.016 if we did everything at the 75%. Looking up the gravity on a chart shows that we now have a 6.6% ABV. If we incorrectly used the 1.016 we would only get 6.3% ABV.

Here's the shorthand:
Calculate PPG for extracts. DME gives 9.2 per pound and LME gives 7.2 per pound. Figure out Attenuation then look up alcohol %. Then add 1.2% ABV for every pound of corn sugar added, all assuming a 5 gal. batch.

I'm sure some of this is not quite right and someone with more brain cells to rub together will post more accurate information and prove me completly wrong. But until that happens, I think this will get you close.

With all of this said, I am not necessarily condoning adding corn sugar to any brew just to boost alcohol content. This is just a way to figure it out.

 

[Chairman Cheyco]

Yeah, what he said.

 

[SkewedBrewing]

If you download beer tools or something like that I think it gives you an ABV based on ingredients and yeast. This is probably close but isn't an exact number.