https://www.panimonurkka.fi/tuote/chateau-acid/
Step by Step
Mill the grains, but be sure to keep the acidulated malt separate. Do not mill the rice hulls. Dough in all but the acidulated malt using 4.0 gallons (15 L) of water with a target mash holding temperature of 149 °F (65 °C). Hold the mash temperature for approximately 60 minutes or until the conversion is complete. Add the acidulated malt to the mash for an additional 45 minutes. Try to keep the temperature as close to original mash temperature as possible using an available heat source. Anything between 144–149 °F (62–65 °C) will work. Raise the temperature of the mash to 168 °F (76 °C) and begin sparging with 170 °F (77 °C) water until you collect 6.0 gallons (23 L) of wort in the kettle.
The total wort boiling time for this recipe is 60 minutes. At the onset of a full rolling boil, add your scheduled hop addition. When there are 15 minutes remaining in the boil, be sure to add your Irish moss or Whirlfloc® tablet to help with precipitation of the hot break. At 10 minutes remaining, add both the ground coriander seed and the salt.
Cool the wort to 68 °F (20 °C), transfer to your fermentation vessel and aerate the wort adequately. Add the contents of your yeast starter to the chilled wort. Ferment around 68 °F (20 °C) until the final gravity is reached, which should be in 5 to 7 days. Rack to a secondary vessel and allow the beer to mature another 5 to 7 days around the same temperature. Your beer is now ready to rack into a keg or bottles along with the priming sugar.