MachineShopBrewing

Recipes 

I was able to test the Rahr and the Crisp MO today. I did 56 grams of crushed malt and added to 150 ml of water. I tested with DI water and got 5.75 for the MO and 5.7 for the Rahr.

I will have to test in the future with the R/O water, as I didn't have any left from last brew session.

I did grab some fresh buffers from midwest supplies yesterday, so maybe that could have something to do with my previous results?

I was just going through my recipes and found this one that I thought was interesting

10.00 lb Pale Malt (2 Row) UK (3.0 SRM) Grain 67.80 %
1.00 lb Barley, Flaked (1.7 SRM) Grain 6.78 %
1.00 lb Oats, Flaked (1.0 SRM) Grain 6.78 %
0.75 lb Chocolate Malt (450.0 SRM) Grain 5.08 %
0.75 lb Roasted Barley (300.0 SRM) Grain 5.08 %
0.75 lb Victory Malt (25.0 SRM) Grain 5.08 %
0.50 lb Caramel/Crystal Malt - 80L (80.0 SRM) Grain 3.39 %


I recorded a 4.6 with 1 tsp CaCl and 1/4 tsp of Lime per five gallons on this mash according to my notes. That is the lowest one I could find and it was for a stout.

So now I think I need to test with the R/O water to see where the base malt comes in with that.

I did use some little plastic cups to hold the buffer solution this time rather than the little jars that I usually use. Perhaps the other jars may be contaminated for some reason. I don't think so, but not sure what else could be a factor.

ajdelange

Recipes 

Neither terribly surprising. I've never checked the Rahr but your MO number is, while 0.05 higher than what I got, not too surprising.

I wouldn't expect much difference unless there is something really weird about the RO machine and I mean really weird such as they cleaned the membranes with acid and didn't flush them.

That is a distinct possibility. When you measure pH you compare the electrical response of your electrode in the sample to the electrical response in the buffer. If the buffer labeled 7 really has a pH of 6 but the meter thinks it is 7 it will think the electrical response from something really at pH 5 is at pH 4. It's really more complicated than that but I hope you get the idea.



That's possible and certainly anything you pour the buffer into should be clean but more important is that the used buffer not be put back into the stock bottle.

DSmith

Recipes 

Was your 5.7ph the Rahr "2-Row Pale" or "Pale Ale Malt"?

MachineShopBrewing

Recipes 

It was the 2-row pale.