New Grain Supplier = Lower Gravity Wort?

Almost all the grain I brew with comes from my LHBS but with this last batch I switched it up and ordered grain from Northern Brewer. Love the grain, great quality, pleased with the packaging and everything else. Will order from them again in a heartbeat BUT ... when I brewed this weekend my wort gravity was .011 less than anticipated (anticipated 1.045, measured 1.034.)

This is the first time that has happened. I am doing BIAB now and I am thinking that maybe Northern Brewer crushes the grains less than the LHBS and that may be part of the issue. I was worried that might be the case and mashed for an additional half hour (1.5 hours rather than 1) just in case. I had a solid temperature of 152F for the first hour although it dipped to 148F by the end. Still, pretty much spot on in that category.

What do you think - should I just pony up for my own grain crusher? Or can anyone think of other reasons why my mash would have come out so much lower?

I order all my grains from NB. With my system, I get around 78% efficiency when I brew lower gravity beers (1.036 OG) and around 60% when I brew the big boys (1.080+).

I haven't seen a difference if I crush my own bulk grains or if they come from NB crushed.

Perhaps it was just a fluke this one time? It's happened to me before... that's why I always measure my pre-boil gravity to adjust before I start boiling.

Did you weigh your grains from NB when you received them..?

BrewChem said:

Did you weigh your grains from NB when you received them..?

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No, I did not. I can't imagine they would be THAT far off.

Northern Brewer will adjust their mills to whatever you request, their default is moderately conservative. Just add a note the next time you order to double crush or set their gap smaller.

rockfish42 said:

Northern Brewer will adjust their mills to whatever you request, their default is moderately conservative. Just add a note the next time you order to double crush or set their gap smaller.

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Cool! Thanks for the heads up. I was pretty impressed with their operation so this doesn't surprise me.

Also, I realized late today that I HAD been removing my grain bag after boil and adding additional hot water (under 162F) to the wort by pouring over the grain bag. This time I just added the water to the wort without pouring over the grain bag. Must have lost about a quarter of the total gravity just by not doing that -- at least I'll make that change and try it again this weekend.

Was it the same brand of malt? If I use Canadian, I get around 68% eff. With Hugh Bairds, I get close to 80%. I have my own mill. You can usually get a grain report on line from the maltster. It will tell you the potential yield.