Ph adjustment

west1m

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in a 5 gallon batch about how much Lactic Acid (liquid) would you expect to use in a mash to lower PH a couple tenth of a percent?
I tossed about a table spoon and did not see much change...
 
in a 5 gallon batch about how much Lactic Acid (liquid) would you expect to use in a mash to lower PH a couple tenth of a percent?
I tossed about a table spoon and did not see much change...

Yes, the pH would drop quite a bit most likely. However, a tablespoon is about 15 mls and that's actually quite a lot. The thing is, it takes quite a while for the pH to drop and so it's not likely to happen quickly enough for it to make a difference in the mash.

You may not be able to taste the 15 mls in the finished beer, depending on your water source. I can use about that much without a flavor impact because my water is very high in bicarbonate, but if you know your water make up we can put it in the software and see what the likely mash pH would be.
 
I have found bu putting in 100g of Acid Malt I can bring down the pH from 5.67 to 5.52 - as an example. It doesn't affect the gravity and only costs a few pence (cents).
 
in a 5 gallon batch about how much Lactic Acid (liquid) would you expect to use in a mash to lower PH a couple tenth of a percent?
I tossed about a table spoon and did not see much change...
That's a very deep rabbit hole.... You didn't provide the information we'd need to troubleshoot (water report, grist, salts, etc.) so I'm assuming you read somewhere to add a teaspoon (Gordon Strong uses that for his recipes made with RO water) of phosphoric acid to the water. It's not that easy, sorry. And if you moved your pH by 0.3, you doubled the acidity. As Yooper mentioned, a teaspoon is about 5 ml. I generally add two to three, depending on the grist.

Water and pH adjustment are about the most complex parts of brewing this side of the actual chemistry of the mash. But simply, as Yooper mentioned above, a tablespoon should have moved the pH quite a bit, keeping in mind it's a logarithmic scale (ph of 5 is 10x more acidic than pH of 6). It is also a low order predictor of beer quality, geek speak for it's not one of the most important factors in your beer's flavor. If your mash pH settled between 5.2 and 5.6, you're fine. You're okay outside of that range but there are risks.
 
pH isn't measured in %, but the concentration of your Lactic Acid is.

Mash pH can vary greatly depending on several factors, the greatest of which will be your grist and the alkalinity of your water. Unless you know your mash pH to begin with, you're just as likely to harm the finished product as you are to improve it with an acid addition. Best advice I can give is to read up on the subject and then use the water tools.
 
I don't remember the numbers at the time , I was trying to drop it back into the mid 5 range ( I use RO water) .
I have used the acid malt before and kinda over did it. But Yoopers answer of " a tablespoon is quite a lot" pretty much answers my question.
 
I don't remember the numbers at the time , I was trying to drop it back into the mid 5 range ( I use RO water) .
I have used the acid malt before and kinda over did it. But Yoopers answer of " a tablespoon is quite a lot" pretty much answers my question.

With RO water, and a very pale grainbill of 10/11 pounds in a 5 gallon batch, you'd be looking at a mash pH under 5.2. If you had any crystal malt or roasted malt, you may be in the 4.7ish range (for a pound of crystal 40L) or lower.
 
I don't remember the numbers at the time , I was trying to drop it back into the mid 5 range ( I use RO water) .
I have used the acid malt before and kinda over did it. But Yoopers answer of " a tablespoon is quite a lot" pretty much answers my question.

This is meant as constructive criticism:
If you're using BF, or any other quality brewing software to design your recipes, you shouldn't need to rely on memory for the numbers, nor should you need to ask how much acid is needed to adjust your mash pH. You have everything you need at your fingertips. With all due respect to Yooper and all of the others who offered help. I fail to see how your question was answered by any of the responses. This due to an almost total lack of information. If you want help here, or on any other forum, please help the people you're asking by exerting the effort needed to give as much accurate information as you can
 
And here I thought you guys didn't get pissy! I merely asked if a tablespoon seemed like it should do something and Yooper told yes it is a lot and I probably wouldn't see it change a mash in the time it is in there.
 
And here I thought you guys didn't get pissy! I merely asked if a tablespoon seemed like it should do something and Yooper told yes it is a lot and I probably wouldn't see it change a mash in the time it is in there.

If you see constructive criticism as being pissy, I plead guilty.
 
And here I thought you guys didn't get pissy! I merely asked if a tablespoon seemed like it should do something and Yooper told yes it is a lot and I probably wouldn't see it change a mash in the time it is in there.

While @BOB357's criticism may have been a little harsh, it was indeed meant to be constructive.
 
I feel that Bob was trying to be constructive, we all "read" things differently. It can be tricky with the types message. I don't "know" Bob, but my experience is that Bob has always tried to be helpful.
 

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