That Log Had a Child v2

DIRECTIONS
Mash at 150°F (66°C) for an hour, run off as usual, then boil for 15–20 minutes. Allow to cool to 115–120°F (46–49°C) and pitch a 1 qt (1 l) starter of WLP672 Lacto Brevis or your favorite Lacto strain (see Brewer’s Notes). Leave the Lacto to do its thing for anywhere from 18–36 hours (shoot for a pH of 3.5 for a decidedly tart beer).

After souring, bring the wort up to 150°F (66°C), add the hops, and hold that temperature for 30 minutes. Chill to 60–64°F (16–18°C), aerate, and pitch two packets of Safale US-05.

Ferment at 65°F (18°C) for 10 days and package as normal. A little heavier carbonation does not hurt!

BREWER’S NOTES
Some strains of Lactobacillus work better at much lower temperatures, so refer to the yeast lab information for best results. Lacto pitch rate is important. There are a number of ways to deal with it, but for this recipe, 1 day prior to making the wort, I use 3 oz (85 g) Briess Pils dry malt extract (DME) in 1 qt (1 l) of water, boiled for 15 minutes, chilled to 120°F (49°C). To that, I add 4 fl oz (118 ml) apple juice, one vial of WLP672 Lacto Brevis, and 1/8 tsp Wyeast nutrient. I gently shake this mixture.

If you have a pH meter, test the wort before you pitch the Lactobacillus to ensure that the pH is below 4.5 (preferably closer to low 4s). If needed, adjust down with phosphoric or lactic acid. Depending on your water, you can just increase the percentage of acidulated malt in future batches. If you have access to CO2, it’s a good idea to blanket the kettle headspace to keep your lactic ferment anaerobic.