Citric Acid, Black Mold, and...Pfizer? The History and Manufacture of the Popular Additive

Citric Acid, Black Mold, and...Pfizer? The History and Manufacture of the Popular Additive

If you are an avid label-reader, you may have seen citric acid in various food products, and if you’re not, you might dismiss it as fancy lemon juice. Citric acid is a commonly used flavor enhancer and preservative that can be found in just about everything you get at your local grocery store. And while the name might suggest that it’s a derivative of harmless citrus fruit, the truth might cause some surprise.

A Brief History of Citric Acid

Citric acid's journey began in the 8th century with its discovery by an Islamic alchemist. However, it wasn't chemically isolated until 1784 by Swedish chemist Carl Wilhelm Scheele from lemon juice. Industrial production kicked off in the 1890s, initially relying on the Italian citrus fruit industry. The game changed in 1893 when C. Wehmer discovered citric acid could be produced from sugar using penicillium mold, though this method wasn’t widely adopted because it was difficult to implement at scale.

The narrative took a compelling turn in the late 1800s as Pfizer started manufacturing citric acid from citrus fruits, coinciding with the boom of the soft drink industry. At the time, Pfizer was still a relatively new chemical company and had only made a few successful drugs. This move marked a significant success for Pfizer, contributing to its rapid growth.

However, the First World War's impact on Italian citrus supplies prompted Pfizer to adopt a method discovered by James Currie, which produced citric acid by feeding sugar to the Aspergillus niger mold. This was a huge turning point for the citric acid industry as it meant that expensive citrus fruits were no longer required and could be substituted for cheap crops like corn. Pfizer scaled production of citric acid using this new fermentation process and the price dropped from $1.25 per pound to $.20 per pound. This drastic cost reduction made processed, packaged food even more attractive to manufacturers.


The Modern Citric Acid Market

Fast forward to the present, and citric acid is a multi-billion-dollar industry, bringing in $2.5 billion per year as of 2016, and is estimated to make $3.9B by 2024 - a 56% increase in just 8 years. Pfizer no longer enjoys a monopoly on citric acid production - In fact, China has become the biggest producer, controlling about 60% of the market.


Citric Acid's Ubiquity in Products

A quick check of your pantry or fridge will likely reveal citric acid's presence in many foods and beverages, such as frozen fruit and vegetables, protein powder, and even wine. Its application extends beyond edibles to cosmetics, personal care items, pharmaceuticals, animal feed, and even construction materials, highlighting its widespread use and potential for skin absorption. Depending on the substance, transdermal absorption can actually be higher than oral absorption. As a little experiment, try tracking how many products you consume or use that have manufactured citric acid over the course of a week. Those small amounts in each product add up quickly. If you actually do this, shoot us an email, because we genuinely want to know. 


Health Concerns and Sensitivities

The focus shifts to the health effects of citric acid, specifically the variety derived from black mold, not citrus fruits, often called manufactured citric acid. Despite being recognized as safe (GRAS), the derivation from black mold and lack of long-term studies on the consumption of citric acid raises safety questions due to its toxic origins.

Some studies report adverse reactions to manufactured citric acid, including acid reflux, stomach pain, and allergic reactions like hives, particularly in those sensitive to mold. Notably, most baby foods contain citric acid derived from GMO corn mold, challenging the perception of its benefit as a vitamin source.

Further investigation reveals that there aren't any long-term studies on consuming large amounts of citric acid, which raises the question of how it could be considered generally safe in the absence of any solid evidence to support this claim.

The Manufacturing Process and Its Implications

The production of citric acid typically follows a process that, while it may differ slightly among manufacturers, involves soaking corn in water treated with sulfur dioxide. This step facilitates the removal of the corn kernel, leaving behind a liquid used in citric acid creation. During this phase, the corn's protein structure breaks down completely. However, this residual protein isn't extracted from the mixture, leading to its hydrolyzation—a process that results in the release of free glutamic acid, commonly known as MSG, into the citric acid. Additionally, citric acid has the capability to react with other proteins it comes in contact with (in processed foods), thus freeing up even more glutamic acid.

MSG, considered an excitotoxin, a type of chemical that can overstimulate neuron receptors and potentially cause nerve cell damage. MSG is typically used in food to increase the flavor profile and make the food more addicting. This aspect is particularly concerning given its inclusion in baby food and the legal loopholes allowing its presence in foods labeled "no MSG."

A small study indicated that manufactured citric acid may cause symptoms such as joint pain, respiratory distress, irritable bowel syndrome (IBS), cramping, and muscle pain. Furthermore, citric acid can irritate the gastrointestinal tract and stomach lining, posing risks particularly for those with inflammatory conditions like GERD or IBS.

Another alarming finding is that citric acid, when combined with sodium benzoate, can form benzene, a recognized carcinogen. This chemical reaction can occur within beverage containers on store shelves, potentially introducing carcinogenic chemicals into popular drinks like Red Bull and Coca Cola.


Natural vs. Manufactured Citric Acid

It should be noted that while natural citric acid from fruits like oranges and pomegranates offers health benefits, the concerns arise from its mass production using GMO corn and black mold.

Corn, thanks to significant subsidies, stands as one of the most cost-efficient options for manufacturers. This is particularly true for yellow dent corn, or field corn, utilized on an industrial scale for its high starch content, making it ideal for producing citric acid, high fructose corn syrup, and other pillars of the American diet.

Regulatory gaps allow for citric acid derived from genetically modified (GMO) corn to be marketed as non-GMO. Additionally, the black mold used in the production of citric acid has undergone extensive genetic modifications, including exposure to gamma radiation, to mutate the strain for increased yield, further complicating the production landscape.


A Call for Awareness and Action

Now, there are some companies that use citrus-derived citric acid, but the labeling often won’t tell you that. The only sure way to know is to contact the company directly and ask for a Certificate of Analysis to verify their source. If they use a synthetic version, write to the company and request that they use a natural source. Generally, you want them to be using an organic source to avoid glyphosate exposure. An even better way to avoid citric acid is to just not consume packaged goods.

We would love to hear from you about your experiences consuming citric acid, and if you’ve noticed any difference from cutting it out of your diet. Shoot us an email at to connect or leave a comment below!

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Coming from a scientific background, what are the sources this post was created from? There are no references that can be traced to make this post reputable. Where was that article published? From how many arrivals was this based off from (one or two is not supportive) How many studies have been done? Studies done on 10 people are two studies in general are too small to make any conclusions. Some people are sensitive to certain food that can cause headaches. It doesn’t sound convincing just by saying “some small studies” is not realizable. To make it convincing and more accurate, there needs to be supporting references from reliable sources (wiki is not one of them)


We generally eat a whole food plant based diet. We were recommended Tajin and against my better judgement we have been putting it in some of our food. Wife and I have both been waking up with headaches and some minor digestion issues We never had before. The suspect ingredient, citric acid is absolutely the flavor We are tasting in it. So much like the ‘Natural Flavors’ or MSG it tingles in our mouths. Thanks for this article. We now have yet another ingredient we need to look out for. It’s so unfortunate we have to scour ingredient labels if we want anything packaged. Best bet, stick to fruits and veggies.


Citric acid is toxic for me, for us all. People just don’t realize it yet. Even the slightest amount gives me a headache. I have eliminated it from my diet which has been incredibly difficult because it’s in most products. I now grow and can my own tomatoes due to all tomato products except ketchup having citric acid. Please, please avoid this preservative like you would avoid a poison. Put it on the same toxic list as MSG, sulfites, nitrates, carrageenan, yeast extract and malted barley flour.


I just ate something that must have had a high amount in it it took me to my knees migraine, dizziness I’m looking at the ingredients not MSG which I’m highly allergic to but corn one of the ingredients and citric acid. Which lead me to research I found you! Thank you thank you thank you. I’m downing benadryl as we speak I’m so messed up right now. This makes me so mad! I sending this to everyone I know! Thank you mailing list oh yes!

Kathy Lewis

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