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Low mash pH

Just did my first all grain brew in a long while. My mash pH was 4.9?? will this ruin my snpa clone attempt :cry:

That is pretty low, in fact lower than I would expect without significant acid additions or a lot of dark malts (which wouldn’t be present in a SNPA clone). How did you measure the pH? Did you do the measurement at mash temp or did you cool a sample to room temp? pH at mash temp is 0.35 units lower than at room temperature, and “correct” mash pH is commonly reported at room temp. So if you measured at mash temp, your room temp pH was actually about 5.25, which is perfect.

That is assuming your pH meter is calibrated.

Regardless, don’t ever assume your beer is ruined until you spit it out in disgust :oops: . Let if ferment and it will most likely turn out fine.

It was at mash temp! ive been worried all arvo till now :cheers: I added some gypsum and soda bicarb to the mash and sparge water using brun water calculations

Ive got a digital ph meter which goes to 2 decimal places

Two most important aspects of PH maintenance are storage conditions and usage conditions.
A. You will prolong the life of the probe and get consistent readings if you always test PH at room temps. For example on a regular mash test I would typically expect to read around 5.6 @ 70f and then consider my mash was around 5.3 at the mash temps as explained above. How I do it is take a small sample in a half pint or smaller jar/cover it and set in a measuring dish filled with a little cold tap water and usually the sample is ready to test in/ around 2 minutes. Plus the small jar is perfect as the probe rests comfortably in the jar without tipping over/ hands free when its taking the measurement.

B. Keep the probe immersed in either PH storage solution ( Usually PH 4 clear buffer with KCL added.) Or if not available use PH 4 buffer for a storage solution. This keeps the junction wet and prevents solution from migrating out of the junction and drying out the probe causing at first slow/ drifting measurements and then complete failure.

C. Always rinse the probe between buffers/ samples/ storage to aid against cross contaminating and skewed samples and keep protein from building up on the probe surface which will cause clogging of the junction if left unchecked.

So it sounds like your SNPA was successful then? Were you able to get the gist of the mineral/ PH calculators pretty quickly?

Thanks itspossible! I think I worked out the mineral/ph additions? I used sodiumbicarbonate to try and increase the alkalinity but started to get too much sodium so I kinda left it a bit low.

I was pretty concerned about a reading of 4.9 so I mixed up half a teaspoon more of sodium bi carbonate in water and added it to the mash. It didn’t seem to change it?

The mash temp started a degree higher and ended a degree lower so im happy with that. My post boil gravity was 1.046 which is a bit low but ok I think :cheers:

[quote=“aussie”]Thanks itspossible! I think I worked out the mineral/ph additions? I used sodiumbicarbonate to try and increase the alkalinity but started to get too much sodium so I kinda left it a bit low.

I was pretty concerned about a reading of 4.9 so I mixed up half a teaspoon more of sodium bi carbonate in water and added it to the mash. It didn’t seem to change it?

The mash temp started a degree higher and ended a degree lower so im happy with that. My post boil gravity was 1.046 which is a bit low but ok I think :cheers: [/quote]

That is the only issue with baking soda is if you need to add a lot of alkalinity it can start to add too much sodium. So it sounds wise that you kept its addition low. At that point the mash was probably buffering any small addition of additional bicarb. Not knowing your setup I am guessing you could have used just a pinch of lime to boost Ca and alk and then the small addition of sulfate/gypsum to bring the SO4/CL balance up.

Yah sure…1.046 will be fine. Instead of around/ slightly over 5% ABV it will hover around 4.7 to 4.8% which is what I lean towards for everyday APA. IE: 1.048SG = 5% typically, many brew days that find unusual efficiency yielding a higher gravity of 1.053+ I usually dilute down before kegging to around 1.048 anyway to find that lower/ more easily session-able beer.

I used about 2 g sodiumbicarbonate and 3g gypsum to the total water. Does that sound ok for my relatively soft water? cheers :cheers:

Those additions sound pretty good, not extreme in any way.
I believe it is the same lime used in gardening. I typically buy mine from stores where you find lots of canning/ preserving jars and the like and find it called pickling lime.

You want to store it in an airtight container as it will revert back to chalk if left open to the environs. Chalk is hard to breakdown in plain water or mashes without using CO2, so many have migrated to using lime. You will need a gram scale as used to weigh hops when using lime. I typically am found using only 0.5-1.0 gram in the mash at most depending on grist. When making a sparge addition for calcium and sulfate you want to use CaCl and gypsum only as you want to keep the alkalinity of the sparge water low and will need a slight addition of acid typically to drop it under 6.0. Sparge PH becomes more of a concern if fly sparging.

As I recall, aussie has very low alkalinity water. I’m assuming that you added a nice dose of gypsum to boost the sulfate? Hopefully you didn’t add any acid or acid malt to the mash?

With low alkalinity water with a big dose of calcium and magnesium containing minerals, the residual alkalinity of the mashing water can be driven very low. That can depress the mash pH significantly. If aussie was blindly following a recipe that called for an acid malt or acid addition, that could have made it worse.

When adding a bunch or calcium or magnesium containing minerals, you do need a bit of extra alkalinity in the mashing water to avoid an overly low mash pH.

Thanks a lot for the great replies!!! you guys are really helping alot :cheers:
Do I just add the bicarb and gypsum to the mash? I added equal amounts to the mash and sparge water.

I only used 2row pale and some crystal 55

My typical OP is to add any mash minerals to the grist before mashing in.
Then during mash in, I add any phosphoric acid needed to lower alkalinity if water/ grist calls for it. You could alternatively use acid malt to lower mash PH also when using very light grainbills with soft water. All depends you just have to punch a few easy numbers and your on top of the situation now with these apps.

Sparge water I add a dose of phosphoric acid when the water is cool to drop alkalinity and then as I start to heat the HLT I add whatever minerals I need and stir well.

As Martin stated many brewers choose to add sparge mineral additions at the boil, but I also feel something is gained by treating the entire liquor first.

Don’t add alkalinity to the sparging water. It’s not needed or welcome.

Thanks a lot for the advice!! ill let you know how it turns out :cheers:

Yes I agree. Anything that adds alkalinity is not welcome in the sparge liquor.

In case it was not clear on the last sentence as these posts were spread apart, I will point out the minerals added to sparge are in my case CaCl and Gypsum to add needed calcium and then to balance my SO4/ CL towards the balance/bitter side in most beers.
I use the brunwater calculation for this sparge addition. Like stated before I feel something is gained by adding the minerals to the sparge instead of the kettle.

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