pH 5.2 and lower efficiency... inconceivable?!

[malkore]

has anyone seen a case where pH 5.2 lowered their efficiency?

I have pretty hard, alkaline water with elevated bicarbonates. My first couple of batches I overshot my OG by a few points.
Last two batches used pH 5.2...same other equip, same crush from the LHBS, and I've been unable to hit my target OG...this last time I missed by .016!!

I plan to experiment with my grain mill when it shows up, and mash to make some starter wort I can freeze...and do one batch with ph5.2 an the other without to see what difference there might be.

for the record my tap pH is 7.8, general hardness is about 220ppm depending on the time of year, and about 170ppm of carbonate hardness.

city water comes from an underground aquifer that's part limestone. quite drinkable, they only add a small amount of chloramine to treat it.

 

[Evan!]

I gained a few points when I started using it, but I wouldn't say that the 5.2 is the cause of the problem. I know the thing you change is always the first thing to get blamed when something goes wrong, but I'd venture to say that it was a coincidence.

 

[malkore]

I suppose its possibly my LHBS adjusted his mill or something.

well the barley crusher has been delivered so I can start figuring out my efficiency issue really soon

 

[DAAB]

I get a better efficiency when adjusting my mash ph using phosphoric acid compared with 5.2, i'm supprised you get a reduced efficiency compared with no ph adjustment though, starch conversion is most effieicent around 5.2-5.3.

 

[malkore]

maybe i'm not using enough ph 5.2

I batch sparge, usually dough in with about 1.25 qts/lb of grain, and only .5 tsp of pH 5.2, adn then another half tsp for the sparge.

i have friday off so i'll be crushing with the new mill and seeing what happens.

 

[DAAB]

The instructions state you should be adding it all to the mash, the quantity is based on the final volume. 1 tablespoon per 5 gallon batch.

 

[BierMuncher]

had to do it...