Citric AcidUpdated 10 months ago

Category: pH adjuster 
Sourced from: non-GMO cassava
Country of Origin: Belgium
Certified to: Nothing yet! 

Citric acid is used to balance the pH of the soap by neutralizing any unreacted hydroxide that’s left over from the saponification reaction. Each batch of soap is carefully tested to see how much alkali remains, and then just enough citric acid is added to catch that alkali. The citric acid reacts so quickly with the hydroxide that it completely bypasses the soap molecules. However, if we were to add too much citric acid, it would undo the soap molecules and create an oily mess.

As of 2022, the citric acid used in our products is derived from the sugar and starch of non-GMO cassava plants although the source plant material can change depending on the supply and availability of raw materials (ex. non-GMO beet molasses or cane molasses). Cassava is an edible root plant that is very robust and a great plant for intercropping – an agricultural technique that supports regenerative farming. 

In the past, we have sourced citric acid from non-GMO sugar beets. Regardless of the sugar source, the citric acid used in Dr. Bronner’s products are always produced from the fermentation of starch and sugar by the Aspergillus niger (A. niger) mold. Microorganisms such as molds and yeasts are widely used in fermentation processes in the food industry: for example, many different strains of yeast are used to ferment malt into beer, and Aspergillus oryzae is used to produce sake and fermented soybeans. 

Health concerns about exposure to A. niger are related to the inhalation of its spores. This is not applicable for the citric acid used as an ingredient in a soap. Following fermentation, citric acid is decanted from the fungal biomass, then treated with sulfuric acid, then evaporated and dried under heat. That treatment kills off any remaining fungal mass and spores. In short, the process of making citric acid is such that bacteria, yeast, and mold cannot survive. And, for good measure, soap is made in temperatures and alkaline conditions that are hostile to microorganisms and their spores.

Dr. Bronner’s products containing citric acid are certified under the USDA’s National Organic Program. 

Found in: Pure-Castile Liquid Soap, Pure-Castile Bar Soap, Organic Sugar Soap, Organic Hair Rinse, All-One Toothpaste, Sal Suds Biodegradable Cleaner*, Organic Shaving Soap

*Sal Suds cleaner shows >60% biodegradation after 28 days per ISO 14593.