Lower than expected final gravity

I brewed an AG IPA last weekend, and aimed for slightly higher mash temps, because I wanted to retain a slight residual sweetness. The mash held around 158-159 F for a little over an hour. I assumed with this temp, I would get some unfermentables.

O.G. going into the primary was 1.067. Hydro sample one week later was 1.009. I guess I was just surprised at how low it is. The recipe is posted below, and I used Wyeast 1056.

I guess this could just be a matter of my thermometer being off. Now that I have two thermometers, I will check to see if they are giving different readings. Any other suggestions as to why it got so low? Thanks!

IPA Recipe

14 lbs. Briess 2-row
1 lb. Briess cara-pils
1 lb. Briess 60L crystal
1 lb. Briess Victory

I'm not sure why in your case. I was going to ask if you used Nottingham, as everything I put Notty in finishes at 1.009, but I see you used Wyeast 1056...

Are you positive your thermo is accurate? That FG sounds kinda high for 159-159 deg mash.

Edit: I see you already thought of that. It'd be my guess anyway.

It could also be the length of your mash. You do not have to go a full hour if you convert earlier than that. In fact, the longer you go, the more opportunity you give the enzymes to create fermentables. Even if you are at a mash temperature that strongly favors alpha-amylase, the beta-amylase still is there and working away on those unfermentable dextrins that the alpha created.

If you are looking to mash at high temperatures for fuller body and maltiness, then you also need to keep a closer eye on conversion. Once you have converted, start your mashout or sparge. Pale malt converts usually converts very quickly, so start checking after about 20-30 minutes.


TL

TexLaw said:

It could also be the length of your mash...If you are looking to mash at high temperatures for fuller body and maltiness, then you also need to keep a closer eye on conversion. Once you have converted, start your mashout or sparge. Pale malt usually converts very quickly, so start checking after about 20-30 minutes.TL

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Thanks, Tex.
I will get some iodine so I can test the conversion during the mash. I would imagine you're correct, and that regardless of temp, I left it too long. Thanks!

jmulligan said:

Thanks, Tex.
I will get some iodine so I can test the conversion during the mash. I would imagine you're correct, and that regardless of temp, I left it too long. Thanks!

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If mash time is the culprit then I'm going to be having one very dry IPA myself. Per Jamil's recipe I was supposed to mash the IPA I did yesterday at 149°F for 90 minutes. I don't have my Mash Tun Thermal Eff. settings just right in my software yet, and I forgot to set the room temp., so I got my strike temp a little high and mashed at 152°F, but I did go a full 90 minutes. With an OG of 1.061 and the possibility of getting down to around 1.009, I'm looking at ~6.8%ABV . I was actually shooting for around 6%.

ma2brew said:

If mash time is the culprit then I'm going to be having one very dry IPA myself. Per Jamil's recipe I was supposed to mash the IPA I did yesterday at 149°F for 90 minutes. I don't have my Mash Tun Thermal Eff. settings just right in my software yet, and I forgot to set the room temp., so I got my strike temp a little high and mashed at 152°F, but I did go a full 90 minutes. With an OG of 1.061 and the possibility of getting down to around 1.009, I'm looking at ~6.8%ABV . I was actually shooting for around 6%.

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I am in a similar boat. With that kind of attenuation, I am looking at 7.4% ABV, which is a bit more than I planned on, especially without the body I was expecting.

Oh well, it's getting nicely dry-hopped, so I'm sure it will get consumed, regardless.