OG of 1.025 from a Northern Brewer All Grain kit....?

[tinman717]

So a few weeks ago I had an incident with a Big Mouth Bubbler breaking (https://www.homebrewtalk.com/f11/big-mouth-bubblers-dangerously-thin-486222/ worth a read if you're at all interested in or currently own a glass Big Mouth Bubbler). Northern Brewer sent me an all-grain cream ale kit as an apology.

The grain bill for their recipe is:

7lb Rahr 2-row pale malt
.75lb Gambrinus Honey Malt
.25lb Belgian Biscuit malt

This all came together in one bag and I put the trust in Northern Brewer that they filled the bag properly....I did not weigh the bag before mashing.

As I have before, I used the calculator on this website to calculate how much mash and sparge water to use: http://www.brew365.com/mash_sparge_water_calculator.php

Poured grains into mash tun, mashed for 60 min with 3 gallons of water at 152 degrees. Heated 6 gallons of water to 180 after 60 mins, poured it into the mash tun, drained, vorlauf, drained. My pre-boil volume was about 7.5 gallons. I discarded .5 gallons of this as my kettle is only 7.5 gallons.

OG came out to 1.025 after a 60-minute boil. I'm not sure what I did wrong here....I know my sparging technique was lazy but could that really account for such a loss in gravity? I don't know my efficiency. Just curious if maybe an issue with the actual kit could have caused this, or if I actually somehow used too much water.

 

[sandyeggoxj]

I haven't plugged that into any software but I'd guess you'd be looking at an og of around 1.040. What efficiency do you normally get? How did the crush compare to your normal?

 

[Yooper]

Well, throwing away .5 gallon of wort would reduce the efficiency, but not by 20 points.

If you didn't batch sparge by stirring the sparge water in thoroughly, that would be the main reason for abysmal efficiency, and throwing away some of the sugars from the wort would make it worse.

If you are batch sparging, drain your first runnings and then proceed with sparging.

Measure your first runnings and only add enough sparge water to get to your boil volume Also, when you batch sparge, stir in your sparge water like you mean it. Then stir some more, and then again. Then vorlauf and drain. Both of those things will make a huge difference.

Mashing with 3 gallons of water would be exactly what I would do. Then, with an 8 pound grainbill, I'd expect 1 gallon of liquid to be "lost" in the grain, and to get 2 gallons of first runnings. I'd then sparge with 5 gallons to get to 7 gallons for my boil volume. Still, measuring the first runnings would be the way to go to make sure the sparge volume is correct. Also, taking a preboil gravity is really important to make sure you're not too low and it can be fixed by adding some DME to the boil if necessary.

 

[tinman717]

Thanks for the great advice! This isn't the first time I've had my gravity come out low but it's the first time it was THIS bad. I definitely did not stir the sparge water well enough. Taking a pre-boil reading is excellent advice. Next week I will put this into action!


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[augiedoggy]

was the mash 152 degrees or the water before you poured it into the grain? If so did you take a temp reading of the mash after poring the water in.... I made the rookie mistake yesterday of pouring my grain into my mashtun full of water too quickly and my mash water went from 170 all the way down to 123!! (I have never seen a drop so drastic). Usually I pump water in and back out o9f the cooler to "preheat" the walls and dough in slowly...
needless to say I added more water and used the rims to bring it up to 152 but it took a while so this will be one dry amber ale... Wont be making that mistake again.... surprisingly I hit my OG ok though.

 

[tinman717]

Wow that's a significant drop in temperature! I believe I heated the water to about 165 before mashing and wound up with a temp of 152 at the beginning of the mash. At the end it was still at 150 degrees.


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