Changes

Trial and error is probably the most practical approach at least to some degree. Post boil, the wort pH is generally around 5.0 - 5.2. Adjusting the pH of wort before pitching ''Lactobacillus'' can then 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 ''LactoLactobacillus''culture. 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).