Final Gravity

I have noticed the last few batches I have made have come in way under expected final gravity. For example, I just finished an amber ale, final gravity was expected at 1.014 come in at 1.008. Looking over my notes from several others I see a similar trend anywhere from .004 to .006 lower than expected. Am I doing something wrong?

UPDATE:

I have gone over my notes for my last 15 batches, and have found than all but one was under the estimated final gravity… The one that was over was a milk stout that I assumed I had too much lactose in. So, it seems that I have yet to get close to any final gravity expectation.

Are you using brewing software? If so, brewing software only gives you an estimate of FG. It is not a guarantee of the actual FG. Does your beer taste good? If so, then it’s probably fine.

Cheers,
Brandon

I am using software for recipe design, yes. Tastes good to me… My biggest concern i guess is that I am looking at entering this brew in a local competition and am a bit concerned about hitting the target gravity and ABV for the style.

Judges don’t know what the FG or ABV of your beer is, so if aroma, appearance, flavor, mouthfeel all are “in style”, the judges will judge it accordingly.

This would be my first entry into any competition. Good information to know. Thanks.

Maybe your wort is too fermentable? Are you mashing at a lower than typical temp and are you sure that your thermometer is accurate?

Typically mash around 153, usually am able to hit that target within a degree or two. The amber ale I just completed is actually a double decoction mash first rest at 122, first decoction raises to 147, second decoction raises to 156, sparge at 170ish… hit all those temps within a degree (higher) on this batch. As far as an accurate thermometer? hard to say. I use a digital so-called instant read that I bought at my home brew supply…

Martin, I don’t know about you, but I’ve found that mash temp just doesn’t make all that much difference any more.  With the high DP of most malts, especially domestic, it seems like you have to go to extremes for it to matter at all.  For instance, using a Rahr base, I mashed the same recipe at 153 and 168 with identical results.

What made you decide to do a 122 rest?

I have made six batches of this amber in an attempt to get it right where i would like it This latest batch is number seven. The third batch is when I started the decoction mashing routine, one minor ingredient adjustment after and this last batch is the third with no changes since.
The way I learned the procedure for decoction mashing at that time was the first rest (protein rest) should be around 122 degrees, then take the first decoction. Perhaps it is unnecessary, but the end product turned out to be exactly what I wanted so I have kept the procedure the same as to not change anything.

some mash schedules are better suited for use with modern, well-modified malts than others.  You might be doing TOO good a job resulting in lower than expected FG.

http://braukaiser.com/wiki/index.php/Decoction_Mashing

If it was only this batch, I would agree. But I seem to always come in UNDER the expected gravity, with every batch…

Your mash schedule should be determined by the malt.  The 122 protein rest is used for undermodified malts, which almost don’t exist any more.