Citric Acid can be used as a chelating agent (like sorbitol, sodium lactate, sodium gluconate) and is used to reduce soap scum, especially useful if you have hard water. It reacts with the lye to form sodium citrate. Use rate is 0.1% to 0.5%. Up to 1 tsp. (1-5 grams) ppo SAP value is 0.571 for monohydrate citric acid. SAP value is 0.625 for anhydrous citric acid. Add citric acid to oils before adding lye water. If you add it to your water, add the lye slowly and carefully. The citric acid will cause some excess bubbling and splashing. When using CA in your soap...you have to add a bit of extra lye to compensate for the oils that the CA brings out of the batter...CA counteracts lye, so to make up for that, I add 0.571 oz of lye for every oz of citric acid. so if you are using 0.25 oz of citric ppo...and making a 32 oz batch of soap: 2 (lbs) x 0.25 = 0.5 oz CA 0.5 x 0.571 = 0.2885 oz extra lye (i would use 0.3 oz)
