Can 88% lactic be diluted 1:1 with distilled water to make 44% lactic acid? I was way off on my ph today which is very very rare and im questioning my 44% solution.
I haven’t used lactic acid as of yet myself. I will use acidulated malt though. I would think that instead of diluting the 88% why wouldn’t you just reduce the amount added to the mash by half? That seems to be easiest and you don’t run the risk of a miscalculation trying to dilute original solution. I would think that just assuming a 50/50 ratio of water to lactic is going to correctly give you the 44% you’re looking for.
If you want to dilute because you have no way to accurately measure smaller amounts. Get a graduated syringe from the drug store. They work great and most have 1/4 ml markings.
No need to dilute it.
Get these pipettes in Amazon (or eBay).
Basic Essential Bottles 100pcs 3ml Disposable Graduated Plastic Transfer Pipettes
You can easily measure 0.5 mL increments.
Cheers
The answer to the original question is yes. I use 88% lactic even though it can be challenging to measure small amounts. Last year I was hitting my mash pH on the nose, but earlier this year I started coming in a bit high and had to increase the amount. I inquired on this forum if my lactic could be degrading but was told that it was stable. I think my municipal water changed a bit. In the last few brews I have increased my lactic acid by about 20% over what Bru’nWater says and have hit my targets again. If you are missing your target it might be your water (or your grain bill) and not the lactic acid.
Thanks. I do have a glass pipet accurate to .1 ml its just often more practical for me to work with a less concentrated solution. I’m not a chemistry wiz and the PH being off today was the first it dawned on me that maybe its not a straight forward calculation.
It can also be changes in the malt from lot to lot
Although I also use full strength I see no reason why mixing 1:1 with distilled water would be a problem. I would think it’s far more likely that something changed in your water or grains than a problem with your acid
Lactic Acid gets diluted when its added to the mash. I use both Bru’n Water and Beer Smith for my calculations and found the best way is to wait 15 minutes after mash-in before testing, sample, add half the lowest recommended amount of acid using a graduated syringe, (as Bob suggested) mix very well and test again. You can always add more if needed. There is really no need to dilute.
But I agree with Whitehausbrews, if you’ve been hitting your mark in the past, than something has changed. The water is the more likely culprit.
Good luck!
When I worked on the pro end, we had to deal with the municipal water changing from season to season. Things like acid rain effect the pH of the water that came out of the reservoir where we got our water. True, municipalities do keep track of what seasonally happens to the water supply, but small changed in pH are not as important as things like bacteria, etc. So it is probably seasonal changes in the water that is causing your issues.
The other thing to keep in mind when adding acid to the mash to adjust the pH is that most of the conversion happens in the first 10 minutes or so of the rest. So waiting 15 minutes to measure after adding the acid might be a bit long. Using acid malt or pre-treating the mash liquor with lactic acid are two pretty good ways to keep things in check. Another option is to change to using either distilled of Reverse Osmosis (R.O.) water and building your water profile from there. I had to switch to R.O. a number of years ago since my well water has an unusually high amount of black manganese which tends to kill the yeast. My well water is also very brackish (400 grains of hardness or 6 parts per thousand) When I started using R.O. with the Bru’n Water calculator, I hit my target pH every time.
Just some additional ideas to ponder.
I too have found that mash pH changes substantially during the early stage of mash. I now delay my initial pH measurements until around the 15 minute mark since it is more stable by then. While I agree that a lot of conversion is occuring in the early mashing stage, using a decent brewing water calculator and adding the full prescribed dose into the mashing water is far better than dosing a little and waiting to see what the result is. With that incremental dosing, you really are hampering your results since the mashing pH is likely well off the mark.
Trust, but verify.
If you are diluting volumetrically 1:1 then you will get something that is stronger than 44% solution, but perhaps close enough. I don’t have properties data for lactic acid at 88%, but I have it for lower concentrations. Diluting 80% lactic 1:1 volumetrically with distilled results in a solution of ~43% lactic acid because the specific gravity of 80% lactic acid is 1.1848.
If you dilute volumetrically 1:1.2 with distilled you should get ~44% lactic acid.
I agree with your assessment, Mr. Brungard. In fact, I use to add my full amount of lactic acid to the mash water while the water was entering my mash tun. Following this practice, I found my mash was far below the required mark. So I began reading various forums to see how others were measuring and began the procedure I’m following now as outlined above. Please note (with all due respect) that I was over-dosing my mash using Bru’n Water alone as my calculator. This is NOT to say there is an issue with the spreadsheet. Instead, I’m certain the errors occurred as a result of incorrect input from me.
All that said, this post is the first time I have read that the majority of the conversion happens in the first 15 minutes. That seems unrealistic, but okay. What I have read was that the mash is most stable at 10-15 minutes and that’s the best time to measure pH. Note: using my current measurement method, my mash efficiency is generally 10-15 points above the mash efficiency predicted in BeerSmith.
So, I plan on brewing another Hefe soon. At which time I will resume my past practice and add acid along with the mash water following the calculations from your new version of Bru’n Water. As I stated above, I agree with your assessment. I simply need to be comfortable with the “trust” part so when I do the “verify” part I’m not inventing a whole new string of sware words. 
Be aware that the pH of the water will be far below your targeted mashing pH after the acid is added. That is normal. The mashing pH will be higher when the grain is added.
If your mash efficiency is 10-15 points above the efficiency predicted in BeerSmith then you need to update your BeerSmith profiles to more accurately reflect your process.
Thanks, Richard, for the advise.