Maximum Amount of Phosphoric acid

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nman13

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Im brewing a Saison and want to get my mash PH down to about 5.2. I have phosphoric acid (25%) and my calculator is calling for 30 ML of addition to the mash. Is this too much? Is there a certain point when adding too much phosphoric acid causes negative effects?

I am mashing with 4.3 gallons for 12 pounds of grain and sparging with four (6 gallon batch.)
 
In "Water Knowledge" , https://sites.google.com/site/brunwater/water-knowledge Martin Brungard states "Phosphoric Acid can also be used for alkalinity reduction and it has little flavor effect since this acid is similar to the malt acids produced through mashing. Malt adds about 1 percent phosphatic compounds to wort."

I don't know if this answers your question, but maybe it will help.
 
When treating your water check the ph. Is your water hard or soft? If using pale malts your ph should be below 6.8 for soft water and as low as 5.8 for hard water to realize a ph of 5.2 to 5.3 in the mash.
That is from Greg Noonan's book, New Brewing Lager Beers.

We pre treat our hot liquor with Phosphoric acid by adding a capful to our liquor tank and checking it after stirring. By trial and error we found that 3.5 capfuls in 15 gallons gets us to 5.8. Since there are different percentages of acid out there you will have to add a little and check it until you find what works for you.

Dark malts and crystal malts will lower your mash ph also so if doing a dark or malty beer you should start off with a higher ph. Greg Noonan also recommends adding the dark and crystal malts later in the mash as they don't have any raw starch so only need to be steeped. Not his exact words but close enough. I just read this ten minutes ago so I haven't forgotten it yet!:D
 
When treating your water check the ph. Is your water hard or soft? If using pale malts your ph should be below 6.8 for soft water and as low as 5.8 for hard water to realize a ph of 5.2 to 5.3 in the mash.
That is from Greg Noonan's book, New Brewing Lager Beers.

I'm not sure how this recommendation was formulated. I looked over my copy of Noonan's book and see no mention of that recommendation. In addition, hardness and softness has very little to do with the need for treatment or the degree to which it should be conducted. Alkalinity is the major driver for acidification. But pH is not a good criterion for determining the level of treatment.
 
I'm not sure how this recommendation was formulated. I looked over my copy of Noonan's book and see no mention of that recommendation. In addition, hardness and softness has very little to do with the need for treatment or the degree to which it should be conducted. Alkalinity is the major driver for acidification. But pH is not a good criterion for determining the level of treatment.

Page 302 in the chapter on infusion mashing. Middle of the page with the paragraph that starts with:

The alkalinity of the liquor is critical to the mash pH.
 
Thanks for the responses guys. I guess I should rephrase my question.

I know that when you add enough lactic acid to lower PH negative sour taste is imparted on the wort. I was wondering if there is something similar for phosphoric acid at a higher threshold. Or is it that as long as i am within the recommended PH range, i shouldn't have a problem adding a lot.

The reason why i ask is because my calculator called for 30ML (25% Phosphoric acid solution) for a 6 gallon batch which I worry is too much and can cause negative effects.
 
I wouldn't just do what a recipe says since your water is going to be different. Just use as much as you need to get the correct ph. For starters I'd just get it around 5.8 -6. It will drop as you mash. Check the mash ph and see where you end up. If you need more acid you can add it to the mash. In other words, it easier to add a little more than to take it back out!
 
You need as much acid as is required to 'neutralize' the alkalinity in the liquor and the grains. Neutralize here means bring the mash pH to the correct value. If the acid is phosphoric and the liquor is hard there is the possibility that the concentrations of phosphate and calcium will get high enough that apatite will precipitate. This requires quite a bit of each. There are some charts at the back of the Palmer/Kaminsky water book that let you know if this is likely.
 
Why not just use lactic acid? You will probably end up using a lot less to get the same results. I use it on every batch and have never tasted a bit of sourness in my beers.


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