2 degree Celsius Mashing temperature less than usual affecting OG severely?

[SwedishBrew]

Hi,

Yesterday, I wanted to try a Golden Ale, 28L batch size. I did mash in according to a recepie, at 64 - 65C for 70 minutes, and then sparged at about 78C, my OG ended up at 1.040 when the was supposed to be 1.052C (According to grainfather community calculator) I was pretty carefull measuring the Barley malt and the water and I did nothing unsual (Besides slightly bigger batch size). The only thing I varied was the mashing temperature, 2 degrees lower, could that really be the issue?

Have been brewing for about 1.5 year and I usually do okay with OG. I usually take a sample after the boil, cool it down to 20 degrees C and then do a reading. The style have always been IPA and there I mash in at 67C for 60 m in, then sometimes I do mashout at 78C then sparge at the same temperature. Sometimes I skip the mash out and go ahead and sparge at 78C after the mash in. I do all grain, Pale ale Malt, usually wheat and oats and some crystal malt and 25 liters batches (excluding waste). In worst case, I have been about 0.02 - 0.03 off my OG Target. I have a Grainfather G30 Connect

Pale Ale Malt
5.600 kg (87.7%)

Caramel Munich II
0.500 kg (7.8%)

Carapils
0.288 kg (4.5%)

 

[VikeMan]

Yesterday, I wanted to try a Golden Ale, 28L batch size. I did mash in according to a recepie, at 64 - 65C for 70 minutes, and then sparged at about 78C, my OG ended up at 1.040 when the was supposed to be 1.052C (According to grainfather community calculator) I was pretty carefull measuring the Barley malt and the water and I did nothing unsual (Besides slightly bigger batch size). The only thing I varied was the mashing temperature, 2 degrees lower, could that really be the issue?

I don't know why you got a much lower than expected efficiency, but the cause would not be a mash temp of 64-65C.

Do you know the actual measured volume and temperature of the post-boil wort?

 

[Nails111]

Anything different with the grain crush this time? Could be a possibility.

 

[hotbeer]

Different crop of grain that maybe had some adverse growing conditions.

Maybe ambient temp and pressure left you with differing amounts of evaporative water loss and the wort is just more diluted than previous.

 

[SwedishBrew]

Hi all,

Yes I measured it roughly on my grainfather. It was slighlty lower than the 29 liters mark after whirlpool (70 degrees). So I guess something like 0.8 - 1 liters off my target. So the volume was a little bit more, but not enough to cause this big difference in OG.

I have used Pale ale Malt from a 25 kg bag I bought, this is the end of it, only 5kg left. That could perhaps be the issue? That the bottom has more of these small malt grains?

Or maybe the sparging? I am pretty sloppy when it comes to sparging, i try to do it like they show in Grainfather instructions, but usually my water pillar is a bit high I guess.