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updated How to Pre-Acidify
There currently is no formula for how much lactic acid to add to a volume of wort due to the different buffering capacities of wort <ref>[http://www.mbaa.com/districts/Northwest/Events/Documents/Study%20in%20the%20Practical%20Use%20of%20Lactic%20Acid%20Bacteria.pdf A Study in the Practical Use of Lactic Acid Bacteria. Greg Doss from Wyeast Laboratories Inc. 2014.]</ref>. Water chemistry spreadsheets and formulas geared towards mash pH adjustments may not be accurate for wort pH adjustments since wort does not contain grain material, however there has been at least one report on MTF that [https://sites.google.com/site/brunwater/ Bru'n Water] can accurately determine how much lactic acid is needed to lower a wort's pH, however this claim requires further investigation. We encourage readers to experiment with water chemistry calculators to see if they can accurate predict wort pH adjustments <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1244954842199394/?comment_id=1245053585522853&comment_tracking=%7B%22tn%22%3A%22R%22%7D MTF Thread with Landon Ortiz. 03/03/2016.]</ref>.
Adjusting the pH of wort can be done fairly easily by taking a trial and error approach. Using 1 mL of 88% lactic acid per .1 shift in pH for 5 gallons of wort is a good starting measurement. As an example, say that 5 gallons of wort has a pH of 5.0 just before pitching the ''Lacto''. Begin by adding 5 mL (1 US teaspoon) of food grade lactic acid to the wort for a target of ~4.4 pH. Stir gently, then take another pH reading. Continue to add 1-2 mL of lactic acid until the wort has the desired pH. Derek Springer has observed that it takes about one tablespoon (15 mL) of 88% lactic acid to reach a pH of 4.2 - 4.5 for 5 gallons of wort <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1290987234262821/?comment_id=1291031577591720&comment_tracking=%7B%22tn%22%3A%22R3%22%7D Conversation with Derek Springer on MTF regarding acidifying wort. 04/24/2016.]</ref>, however a higher amount may be required if the brewer's water is high in bicarbonate (24 mL for 5 gallons of wort to reach a pH of 4.4 was reported by Sean McVeigh for his water which contains 375ppm of bicarbonates <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1290987234262821/?comment_id=1291031577591720&reply_comment_id=1291118190916392&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Sean McVeigh on MTF on acidifying wort. 04/23/2016.]</ref>). Once a pH of 4.0 - 4.4 is reached, pitch the ''Lactobacillus'' culture. This small amount of lactic acid shouldn't have much of an impact on flavor. If a more precise method for determining the required amount of lactic acid is required, a sample of the wort can be pulled and lactic acid or phosphoric acid can be added to it until the target pH is reached, and then that amount can be scaled up (a micropipette might be required to measure very small amounts of lactic/phosphoric acid).
====Measuring Wort Buffering Capacity====