Why is my OG so low?

[RVAbrew]

So I did an all grain stout today and my og came in super low. Was supposed to be 1.080 but instead came in at 1.052, and that's after temp adjustment. Expected og was calculated by the beersmith app, and unless I got screwed by the local brew store, all grains called for in the recipe were accounted for. Here's what I did for the 5gal brew:

Heated 4.5 gal mash water to 178, poured in 10 gallon Cooler mash tun, added grains, stirred until I hit 154 degrees, closed lid and let it sit for 1 hour. Vorlaufed 4 times, drained wort into kettle. Added 4.5 gal batch sparge water at 170 and stirred again till 154. Let sit 15 minutes, vorlaufed 4 more times, and drained into kettle.

Now I did end up with about 1 gallon too much wort and I didn't want to waste it, so I boiled what would fit into my kettle and then added the extra gallon once I'd boiled off enough to fit it in. That didn't take long, maybe 15 or 20 minutes. Any ideas what went wrong with my og?

 

[paperairplane]

What was efficiency in brewsmith? How did crush look? What's grain bill look like?

 

[RVAbrew]

I didn't calculate efficiency. The crush looked a bit fine, there was some powder at the bottom of the bag. But then again I haven't been brewing long enough to know when I've got a good crush. Here's the grain bill:
8lb 8 Oz maris otter
12 Oz roasted barley
12 Oz caramel/crystal 60
1lb 4 Oz munich
8 Oz flaked oats
8 Oz flaked barley
8 Oz cara pils
1lb chocolate malt

Thanks

 

[MichaelBrock]

Heated 4.5 gal mash water to 178, poured in 10 gallon Cooler mash tun, added grains, stirred until I hit 154 degrees, closed lid and let it sit for 1 hour. Vorlaufed 4 times, drained wort into kettle. Added 4.5 gal batch sparge water at 170 and stirred again till 154. Let sit 15 minutes, vorlaufed 4 more times, and drained into kettle.

After pouring the 178 degree water into the mash tun did you let it cool at all before adding the grain? In my experience, I only lose 3 or 4 degrees when adding the water to the cooler. If you added the grain with the water at 175ish then you most likely denatured most of your enzymes and that would lower your OG.

Just out of curiosity, why, after adding your sparge water, did you stir it down to 154 again? The point of adding your sparge water at 170 is to denature whatever enzymes are still active, i.e. to stop conversion. So the cooling to 154 isn't at all necessary. Add your sparge water, stir it like crazy for a few minutes, and run it off as quickly as you want.

Beyond that, OG issues are often caused by having a bad grain crush.

 

[brew_ny]

Now I did end up with about 1 gallon too much wort

could be your problem

 

[RVAbrew]

I guess I should have let it cool down some from 178 before I threw the grains in cuz I did add them right away. As far as letting the sparge cool down to 154 I guess I just thought that's what I was supposed to do. I need to add less sparge water next time I think. So if I fix these things and assuming I have an ok crush, you think I should be OK next time?

 

[pricelessbrewing]

I didn't calculate efficiency. The crush looked a bit fine, there was some powder at the bottom of the bag. But then again I haven't been brewing long enough to know when I've got a good crush. Here's the grain bill:
8lb 8 Oz maris otter
12 Oz roasted barley
12 Oz caramel/crystal 60
1lb 4 Oz munich
8 Oz flaked oats
8 Oz flaked barley
8 Oz cara pils
1lb chocolate malt

Thanks

That recipe, at 70% effeciency, and 5.5 gallon batch comes to 1.059 expected OG. Dunno how they got 1.080 unless it's like 96% effeciency, or a smaller batch size like 4G.

Check your recipe at Brewers friend.com to confirm.

Are you doing mash in a bag in a cooler? If so, my calculator below might be of interest to you, just make sure you add 4 degrees or so to the strike temp to adjust for heating the mash tun.

Assuming that's a 5G recipe, your efficiency was about 55%. I would first check out your crush, at that has the greatest effect on your efficiency. Next up I would say your water volumes, if you end up with 5.5 but the recipe is 5 then your efficiency goes down about 5% due to dilution.

 

[paperairplane]

I didn't do any math - but 8# base is not going to get you 1080 wort. My question on efficinxy was if this is set too high in BS, your numbers will all be off.


Sent from my iPhone using Home Brew

 

[MichaelBrock]

I guess I should have let it cool down some from 178 before I threw the grains in cuz I did add them right away. As far as letting the sparge cool down to 154 I guess I just thought that's what I was supposed to do. I need to add less sparge water next time I think. So if I fix these things and assuming I have an ok crush, you think I should be OK next time?

There are only so many things that can go wrong, so fix these few and try again. Then fix the things that go wrong that time, etc. Eventually, after probably not many more iterations, you'll have the process dialed in. Once you have it down it becomes second nature. Software like Beersmith or websites like Brewersfriend.com can really help.

That said, I think fixing these two things (mash temperature and volume) will be a big step in the right direction.

Edit: I didn't check your recipe to see if the predicted OG was correct, but others have pointed out that your expected gravity might be too high for your malt bill. Definitely something to check. This too is where the software can help. Try brewersfriend.com

 

[TipsySaint]

You might also want to make an equipment profile that fits what you have....beersmith lets you do this but you need to know things like boil off rate, and various vessel and transfer losses...

 

[RVAbrew]

Thanks guys, all good input. I made up the recipe myself in BeerSmith and with all the grains I added in, it gave me an og of 1.080. I'm just assumed that's what I was shooting for.