OG is really low...

[zprice07]

I tried to brew a batch this past weekend and am not sure what happened. Beer was made haha, but my OG came out way lower then I had planned. I calculated that my OG should be 1.063 using a computer program. However, when I took the actual readingit came out much lower 1.035. What went wrong? Everything went smoothly. I thought I did everything right but apparently that is not the case. Any thoughts as to what happened and how I can fix it? I posted a bunch of information below. Thanks for the time.

5 Gallon Batch

Grain Bill:
American 2-row Pale- 8 lbs
Amber Malt- 1 lbs
Light Munich Malt- 1.5 lbs
Vienna Malt- 1.5 lbs
2-row Carapils Malt- .5 lbs

The our target mash temp was 154, but our actual mash temp was 151. We mashed for one hour.

Our water to grain ratio was 1.25 qt/lb of grain.

We used Beer Tools Pro to calculate our OG and our efficiency was set at 75%.

Our pre-boil target was 6.25 gallons because for an hour boil we usually boil off a little bit more then a gallon. Our actual pre-boil volume was just a hair over 6 gallons.

The LHBS crushed our grains.

 

[Indyking]

You just got a very low efficiency, so it seems.

What was you post boil volume? Did you sparge (just checking)?

 

[npauley88]

Did you check the OG at room temperature or was the wort hot?

 

[beeber]

There are a lot of variables here.

Describe you sparging setup. Did you batch sparge or fly sparge? How quickly did you sparge? What was the quality of the grain crush? What was the sparge temperature?

Since your grains were crushed at the store, I am going to assume the crush was good.

Could be any or all of these.

 

[zprice07]

We did a batch sparge probably 5 minutes after the mash drained. The grain crush seemed pretty good, but I did not thoroughly inspect it. The sparge temperature was about 165 if I recall correctly.

Post boil volume was 5 gallons.

 

[TipsyDragon]

if you can give us a picture of your mash tun.

 

[Indyking]

165F for me is way too low, but I fly sparge, which cause the water to loose a lot of heat during the sparging process. That would be one thing hurting your efficiency.

Was this your first AG or first use of any new equipment?

 

[geezerpk]

I get some lower than expected OGs at times, too. I agree with IndyK the sparge temp could be a factor. I've been experimenting with doing a mashout with boiling water using about half the volume of the mash liquid. This brings the temp up pretty close to 170 in most cases. Then I drain the mash and and mashout and add 170-175º sparge water to cover the drained grain. Let this sit for about 10 minutes and drain until you get your boil volume. Add more sparge water if necessary to get your volume.

BTW, I mash in a huge bag inside of an insulated bucket with spigot. It's a pretty low-tech setup but works decently for me. That being said, I feel good when I get 70% or so efficiency by my rough calculations. I hope to get better with time.