What is Potassium Benzoate (E212)? Uses, Safety, Side Effects

What is Potassium Benzoate (E212)? Uses, Safety, Side Effects


Table of Contents

Potassium benzoate(E212), a chemical compound that is the potassium salt of benzoic acid, is primarily used as a food preservative. It prevents bacteria from growing in foods and drinks, such as sodas and salad dressings, as well as medicines and cosmetics like lotions and deodorants, according to Drugs.com. 

This type of preservative also plays a vital role in foods to which color has been added, such as fruit juices.

What is potassium benzoate?

Potassium benzoate (also known as benzoic acid potassium salt) is a preservative used in foods and beverages, such as soft drinks, salad dressings, jams, and jellies. It can also be used as an antiseptic, according to the Food and Drug Administration (FDA). The FDA has set an adequate daily intake (ADI) for potassium benzoate of 0–0.5 mg per kilogram body weight per day.

Potassium benzoate is used in many food products to prevent mold growth on the surface of foods. It does not kill molds that have already grown into the food or beverage, but it prevents them from growing on the surface.

Potassium benzoate is a weak organic acid that prevents mold from growing in foods and beverages. When it reacts with ascorbic acid (vitamin C), it produces benzene, which has been shown to cause cancer in laboratory animals when they are exposed to high levels over their lifetimes, particularly when they are exposed prior to birth or during infancy when they have not yet built up an immune system that could protect them against cancer-causing agents.

What is potassium benzoate used for?

Potassium benzoate is an additive and preservative that prevents bacteria from growing in food and drinks. It is added to products such as soft drinks, fruit juices, jams, pickles, and salad dressings. It can also be found in wine and beer.

Potassium benzoate is also used as a food additive with E number E212, according to the International Numbering System for Food Additives (INS).

In medicines, potassium benzoate is commonly used as an antifungal agent to treat vaginal yeast infections. It’s also used to treat other kinds of fungal infections like athlete’s foot or ringworm. Potassium benzoate may be applied topically or taken by mouth in combination with other medicines.

Potassium benzoate is also used in mouthwashes as an antiseptic agent to prevent infection after oral surgery procedures such as tooth extractions or dental implants. When mixed with salt (sodium chloride), potassium benzoate forms a chemical called benzocaine that temporarily numbs the tongue when placed directly on the surface of the tongue during dental procedures such as root canals or fillings (endodontics).

What is potassium benzoate in food?

Potassium benzoate is a common additive used in foods and beverages to prevent the formation of harmful bacteria. It is often added to acidic foods such as fruit juices, carbonated beverages, and wine.

Potassium benzoate is approved for use as a preservative in foods by the U.S. Food and Drug Administration (FDA). It’s also approved for use in cosmetics and pharmaceuticals.

In addition to its use as a preservative, potassium benzoate also has several other uses in food production

Potassium benzoate is used as a preservative in many foods and beverages. It’s often used in conjunction with ascorbic acid (vitamin C) or sodium benzoate to prevent the growth of harmful bacteria.

Potassium benzoate can be found in:

Soft drinks, including carbonated soft drinks, some fruit juices, and energy drinks

Fruit-flavored beverages and sports drinks

Dairy products, including nondairy creamers, frozen desserts, and sweetened yogurt drinks

How is potassium benzoate made?

The reaction between benzoic acid and potassium hydroxide produces potassium benzoate.

1. Potassium Hydroxide (KOH) is added to a mixture of benzoic acid and solvent. This produces a solution of the potassium salt of benzoic acid. The solvent is then evaporated, leaving potassium benzoate in the solid state.

2. The resulting product may be purified by recrystallization or vacuum distillation before being used for commercial purposes.



Powder or granules that are white or colorless.



Other Names

  • Potassium salt of benzenecarboxylic acid
  • Potassium salt of phenylcarboxylic acid

CAS Number


Chemical formula


Molar Mass

160.213 g·mol−1

Melting Point

>300 °C


Functional Group

Aromatic benzene ring and ester group. Ester groups react easily with other groups.



Water: 73.83 g/100 mL (25 °C), approximately 21 times that of benzoic acid. When it comes into contact with water, it dissociates into two distinct parts, the benzoate anion, and the potassium cation. A conjugate base of benzoic acid is the benzoate anion.

In organic solvents: slightly soluble in ethanol, insoluble in methanol, insoluble in ether.


The pKa of benzoic acid: 4.2.

The preservation function is better in low-pH below 4.5 products.

Preservation Mechanism

The mechanism of action is the same as that of sodium benzoate and sorbates, but different from that of Natamycin, a bio preservative. Potassium benzoate dissociates in water and combines with a proton to form benzoic acid. Undissociated benzoic acid enters microbial cells and inhibits their growth. This is how it works and how it preserves food.

What is the application of potassium benzoate?

In the past, it has been used less than sodium benzoate, but now it appears that the market demand for it is increasing. As a substitute for sodium benzoate, potassium benzoate is used primarily in acidic foods where sodium content needs to be reduced. Foods containing the following ingredients:

  • Soda
  • Juice
  • Cider
  • Margarine
  • Syrup
  • Jelly
  • Dressing

Here’s what soda manufacturers have to say about it.

  • Coca-Cola: Preservative used to protect taste.
  • Pepsico: Used in carbonated soft drinks such as Diet Pepsi and Sierra Mist to preserve freshness.

Is potassium benzoate safe?

It has been approved as a safe preservative by the European Food Safety Authority (EFSA) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and can be used in a variety of products such as soft drinks.


Sodium benzoate and potassium benzoate are both salts of benzoic acid, but sodium benzoate is used in food & beverage as a direct preservative, while potassium benzoate is used in polymers for food contact surfaces as an indirect food additive.

Nevertheless, the FDA stated potassium benzoate has the same function as sodium benzoate, which is used to inhibit the growth of bacteria, yeasts, and mold in beverages. Heat and light exposure may stimulate the formation of benzene (a known carcinogen) by the reaction between vitamin C (naturally or added) and potassium benzoate in drinks.

I believe potassium benzoate can be used in the USA as a food preservative like sodium benzoate, since Coca-Cola and Pepsi sell their products in the USA, such as Diet Pepsi. The FDA’s official website does not provide solid evidence that it can be used as a direct food preservative. I would appreciate it if you could let me know when you have found such information.


As an authorized food additive, potassium benzoate (E212) is listed in Commission Regulation (EU) No 231/2012 under “Additives other than colors and sweeteners”.

Approved uses

The maximum use levels are 150 to 6,000 mg/kg, and it is listed alongside benzoic acid and calcium benzoate (E210-E213). The product can be used with sorbic acid-sorbates (E 200–202) and p-hydroxybenzoates (E 214–219).

Safety Re-evaluation in 2016

Following the studies of no genotoxicity, no reproductive toxicity, and no carcinogenic potential, and other studies, EFSA determined a group ADI of 5mg/kg BW/day.

UK Food Standards Agency

In the “Preservatives” category

Food Standards Australia New Zealand

In Australia and New Zealand, code number 212 identifies it as an approved ingredient.


Classification: food additives, preservatives.

ADI: was set at 5 mg/kg BW of benzoic acid in 1996

Potassium Benzoate vs Sodium Benzoate

Potassium Benzoate and Sodium Benzoate are both common food preservatives. They’re usually found in fruit juices, carbonated beverages, salad dressings, and condiments.

Both benzoates are used to prevent the growth of bacteria, yeast, and mold in foods. They’re also used as antifungal agents in medicines.

Potassium Benzoate vs Sodium Benzoate: What Are The Differences?

The main difference between potassium benzoate and sodium benzoate is the type of molecule that makes each one up. Sodium benzoate is made up of one sodium atom attached to two carboxyl groups (which contain carbon, oxygen, and hydrogen atoms). 

Potassium benzoate has two potassium atoms instead of just one sodium atom. Both molecules have very similar chemical properties, but there are some differences that may be important for some people.

One of the main differences between sodium benzoate and potassium benzoate is that sodium benzoate has one less atom than potassium benzoate. This means that there are fewer atoms present in sodium benzoate than in potassium benzoate. This can make a difference when it comes to how much energy is required to break down these two molecules.

The chemical structure of both molecules is similar, so they have similar properties as well. Both molecules contain one carbon atom, two oxygen atoms, and four hydrogen atoms. 

However, because potassium has an extra proton (which makes up each electron), its atomic number is 19 compared with sodium’s number of 11. This means that each electron in potassium is more tightly bonded than it is in sodium (because it has more protons), which leads to stronger chemical bonds between these atoms in both molecules.

What are the side effects of potassium benzoate?

Potassium benzoate is a food preservative that is used in products such as soft drinks, fruit juices, jams, jellies, and condiments. The Food and Drug Administration has approved potassium benzoate at a maximum level of 0.1 percent in foods. The European Union has set the limit at 0.5 percent of the food item’s weight.

The side effects of potassium benzoate are similar to those of sodium benzoate and include:

  • Skin irritation. This is most common with topical application.
  • Digestive upset. This may include nausea, vomiting, or diarrhea. This can occur if the compound is taken orally in high doses.
  • Dizziness or lightheadedness, particularly when standing up quickly after taking the medication.
  • Headache may be severe enough to cause a person to stop taking the drug.

Where to buy potassium benzoate?

You can buy potassium benzoate from a variety of online retailers. Amazon, eBay, and Alibaba all stock the chemical.

If you are looking for a specific supplier, search for ‘potassium benzoate’ on Google and sort by price. This will show you who is selling the product at the lowest price.

if you buy a large quantity of potassium benzoate for your company, you can consider purchasing from Grade Chemical. Which is one reliable potassium benzoate supplier in China. they can supply you with a much more competitive price than the local market price.

Frequently Asked Questions

Is Potassium Benzoate Effective at Raising Potassium Levels?

Potassium benzoate has been linked to causing high blood pressure, increased risk of leukemia and lymphoma, as well as other health problems. In addition, it can potentially cause an increase in potassium levels in the body if taken in large amounts.

However, there’s no evidence that potassium benzoate actually raises potassium levels in humans. In fact, studies have shown that it may actually lower them by increasing the excretion of potassium through urine. This means that while you might see an increase in your blood level of potassium after eating foods containing this preservative (since more is being excreted), you won’t actually be getting any more into your body than you would without it being present at all!

Is Potassium Benzoate Natural?

Potassium benzoate is synthesized by combining benzoic acid with potassium hydroxide. This process does not require any animal or plant source materials, and therefore it cannot be considered natural nor synthetic. The resulting product is identical to what would be created from natural sources.

What is another name for potassium benzoate?

Potassium benzoate is also known as “salicylic acid”, “benzoic acid”, “butanoic acid”, and “salicylic aldehyde”.

Is potassium benzoate acidic or basic?

Potassium benzoate is a weak acid, meaning it’s not very reactive and doesn’t dissociate easily.

Is potassium benzoate bad for you?

No, potassium benzoate is not bad for you. In fact, it’s an ingredient in many foods and drinks that you probably eat and drink on a regular basis.

Potassium benzoate is a preservative that prevents foods from spoiling. It’s often used in soft drinks, salad dressings, and baked goods like bread and muffins. It can also be found in jams and jellies.

Yes, potassium benzoate is in soda. It’s a preservative that helps prevent the growth of certain bacteria and yeasts in food and drink, including soda.

Is sodium benzoate the same as MSG?

No, MSG and sodium benzoate are not the same. They both contain sodium, but they are different chemicals. Sodium benzoate is a preservative that can be found in things like soft drinks and salad dressings, while monosodium glutamate (MSG) is an amino acid that enhances the flavor of food.


This article has covered everything you need to know about potassium benzoate and why it is considered safe. Further, the risks of this preservative have been analyzed as well. To keep yourself safe from any possible health issues, stick to consuming products that are labeled organic.

If you have any questions about potassium benzoate? Let us know in the below comments.

Sophie Feng

Sophie Feng

Sophie Feng is the author of gradechemical.com, she is the co-founder of the grade chemical network. She has been in grade chemical company since 2017, with a working knowledge of food chemical .

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