Oxalic Acid: The Science (& Magic) of Bar Keepers Friend

August 30, 2021

Bar Keepers Friends has been going strong since 1882 and there’s a very good reason why. For over 138 years, the recipe for BKF’s core product has remained remarkably similar. Even as we continued to expand our product offerings, we’ve used many of the same ingredients for several decades and more decades to come.

So, what makes Bar Keepers Friend so good? Let’s find out now!

What’s In Bar Keepers Friend?

In order to find out what makes BKF so good, we need to figure out the very things that make our product work. While some of BKF’s ingredients are “trade secrets,” the core ingredient isn’t – Oxalic Acid.

Back in 1882, Indianapolis chemist George William Hoffman discovered the power of oxalic acid entirely by accident when cooking rhubarb. When he was done cooking the rhubarb, he noticed that the very pot he cooked it in was cleaner and sparkled more than ever before. As a chemist, this piqued Hoffman’s curiosity – so he quickly got to work to figure out how it happened.

But first things first….

What is Oxalic Acid?

Oxalic Acid is a white crystalline solid and strong organic acid that naturally occurs in many known fruits and vegetables such as rhubarb (like George William Hoffman discovered), spinach, beet leaves, swiss chard, and more. Given its acidic nature, it has and continues to be used for cleaning and brightening agent — most notable for removing rust from metals as well as phenomenal for removing hard water stains and mineral deposits like calcium and lime.

See the power of Oxalic Acid in action in this video from YouTuber, Clean Freak & Germophobe. 

Fun Fact: Did you know that some beekeepers use oxalic acid as a way to keep Varroa mites at bay?  While BKF is safe around your family and your pets, it’s been proven to get rid of the mites that cause harm to honey bees. Even cooler is that it doesn’t have an adverse reaction to the bees themselves.

How is Oxalic Acid Made?

Oxalic acid can be made and extracted in a number of different ways. Like our friend George William Hoffman, you can boil and extract the organic compound from rhubarb leaves, or any of the fruits and veggies mentioned above. Other chemists have opted to use nothing more than sugar and nitric acid to create it. Here at Bar Keepers Friend, our oxalic acid generally comes from plant/vegetation waste from industrial suppliers. 

Naturally, given the time and effort that goes into making oxalic acid, you’re better off leaving production to the professionals. Even though oxalic acid is a core ingredient, it makes up just under 10 percent of BKF’s cleanser. You don’t want to just use straight oxalic acid to clean your cookware or wipe down your counters. 

While the process for making oxalic acid is pretty cool, it’s probably a lot easier to pick up a can of Bar Keepers Friend from your local grocery store!

About the Author

Felicia Savage is a content strategist, agile marketing enthusiast, and Digital Marketing Manager at Bar Keepers Friend. When she isn’t writing about her love for Bar Keepers Friend (or wiping down her stainless steel sinks), you can find Felicia sparring at her muay thai gym, doodling in her sketchbook, or watching silly cat videos on TikTok.