What is Potassium Carbonate E501(i) in Food? All you need to know

What is Potassium Carbonate E501(i) in Food? All you need to know


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In this blog, we have sought to furnish you with all the information relevant to what Potassium Carbonate E501(i) is, how it’s used in a number of applications, and many other common uses of Potassium Carbonate E501(i).

What is potassium carbonate?

Potassium carbonate is a chemical compound with the formula K2CO3. It is a white, water-soluble solid that acts as a base. Potassium carbonate is used in the manufacture of glass, soaps, and detergents and as a food additive.

Potassium carbonate is produced by the reaction of carbon dioxide with potassium hydroxide. In industry, it is often produced by the reaction of potassium chloride with baking soda:

KCl + NaHCO3 → NaCl + K2CO3

Potassium carbonate can also be prepared by reacting potassium chloride with sodium bicarbonate.

How is potassium carbonate made?

Potassium carbonate is a white solid that is used in many different industries. It is commonly used in the manufacture of cosmetics, pharmaceuticals and paper. Potassium carbonate can be produced by a number of different methods.

Potassium carbonate is produced by heating potassium hydroxide (KOH) with carbon dioxide at high temperatures. The resulting product is called potassium bicarbonate, which can be heated further to produce pure potassium carbonate crystals.

There are several other methods that can be used when making this compound as well. One method involves grinding up potassium chloride (KCl) into a fine powder and mixing it with powdered charcoal (C). This mixture is then heated until it melts, which allows for the formation of potassium bicarbonate crystals. Another method involves dissolving potassium hydroxide in water followed by adding finely ground limestone (CaCO3) until all of the CO2 has been absorbed by the solution.


Other names Potash, Pearl ash, Carbonate of potash, K carbonate
CAS number 584-08-7
Chemical formula K2CO3 · nH2O, n = 0 Anhydrous, n = 1.5 Sesquihydrate
Molecular weight 138.20 (anhydrous)
pH of 10% K2CO3 11.6
Melting Point 1636°F (891°C)


  1. Anhydrous: a white, very hygroscopic powder, easily absorbed by water in the air and may agglomerate.
  2. Hydrate: It is a white, free-flowing, dustless, translucent crystals or granules.
  3. Liquid versions are also available in the market.


This salt is very soluble in water, with a solubility of 113.5 g/100ml at 25oC, which is better than sodium carbonate. When dissolved in water, it forms a strongly alkaline solution and dissociates potassium cation (K+) and carbonate anion (CO32-) as shown in the following equation.
K2CO3 ===> K+ + CO32–
CO32- is amphoteric and exists as the following carbonic acid equilibrium:
CO32- + H2O HCO3- + OH-
HCO3- + H2O H2CO3 + OH-
Ethanol is insoluble in it.

What is the purpose of potassium carbonate?

Potassium carbonate is a water-soluble salt with applications in the production of glass, detergents (soaps), ceramics, fertilizers, agrochemicals, pharmaceuticals, food, feed, fire extinguishers, and drying agents for solvents.
Based on density and solubility, potassium carbonate can be divided into heavy and light types. The heavy type of potassium carbonate is mostly used in glass, ceramics, and fertilizers. Light types are mainly used in food, pharmaceuticals, and agrochemicals.


Food grade is mainly used as an acidity regulator, and its common uses in food are as follows:
  • Cocoa: Alkalized cocoa can be made to reduce the acidity of natural cocoa beans and darken cocoa powder.
  • Wine: When it comes to wine, it can also be used as a buffer to lower acidity levels.
  • Bakery: In baking, it was commonly used as a leavening agent to raise bread, but sodium bicarbonate was later substituted due to the bitter aftertaste. However, it can be substituted for sodium bicarbonate in baked goods where a low sodium content is desired.
  • Ramen Noodles: In Kansui, Ramen noodles are used to improve texture and color.
  • Marinades: used to buffer meat marinades.
  • Milk powder: Milk powder is used to regulate the acidity of milk and cream powders.
  • Raisins: Raisins are a method of drying grapes and turning them into raisins.

Ramen noodles

Have you ever wondered why ramen noodles can be stretched so long and not break after repeated stretching?
This is potassium carbonate, which interacts with protein and hardens, makes elastic, and changes the color of ramen noodles. It raises the pH of dough and also reduces the cooking time of noodles.
The two main components of Kansui (lye water) are potassium carbonate and sodium carbonate. Using wheat flour to make thin ramen noodles with a high protein content, the proportion of the former is higher. When used to soften noodles with low protein content, the percentage of latter is high.


A top USA manufacturer reported that 44% of the total consumption of potassium carbonate is used in glass production. This is a process which improves glass transparency, electrical resistance, strength, and refractive index. Among its uses are alkali barium, lead or strontium silica glasses that are used in television tubes, laboratory glasses, optical glasses, etc.


In ceramic production, potassium carbonate can be used as a raw material for ceramic frit. The primary purpose of this process is to lower the melting temperature of the frit and increase the expansion coefficient of the frit. The titanium dioxide frits contain K2O, and it is used in the appliance industry.


It makes soap softer than sodium-based soaps.

Is potassium carbonate safe to consume?

Potassium carbonate, also known as potassium hydrogen carbonate and potassium bicarbonate, is a white solid. It is typically used in the production of detergents, soaps, and other cleaning products. Potassium carbonate can be found in many common household items, including toothpaste and mouthwash.

Potassium carbonate is safe to eat when ingested at normal levels. The amount of potassium carbonate consumed in toothpaste or mouthwash is not enough to cause harmful side effects. However, you should avoid eating large amounts of potassium carbonate because it can cause stomach problems such as nausea and vomiting if consumed in large amounts over a long period of time.

Ingestion of very large amounts of potassium carbonate can lead to an upset stomach and diarrhea. If you consume too much potassium carbonate, you may experience an electrolyte imbalance that leads to low blood pressure or muscle weakness due to low calcium levels.


As a direct human food ingredient, potassium carbonate is generally recognized as safe (GRAS). Food is used as a flavoring agent and adjuvant, nutrient supplement, pH control agent, or processing aid with no restrictions other than current acceptable manufacturing practices.


Potassium carbonate E501(i) is listed as an authorised food additive in Commission Regulation (EU) No 231/2012 in the category “Additives other than colours and sweeteners”.


Functional Class: food additives, acidity regulator.

Admissible daily intake: ADI “not limited” was set in 1965.

How to identify potassium carbonate?

Potassium carbonate is a chemical compound with the formula KCO. It is commonly encountered as a white solid that dissolves in water, producing carbonic acid (HCO). This solution can be used to determine potassium in biological samples such as blood, urine and water. Potassium carbonate is used to prepare potassium hydroxide and potassium bicarbonate (KOH or KHCO).

Potassium Carbonate Identification by Color

Potassium carbonate may be identified by its characteristic color. In solution, potassium carbonate gives off a faint yellow-orange color. The color of potassium carbonate depends upon its concentration: at high concentrations it appears yellow-green, while at lower concentrations it appears more greenish.

What is potassium carbonate soluble in?

Potassium carbonate is a white powder which is soluble in water and alcohol. It is used as an electrolyte in electroplating, as an oxygen scavenger in air conditioning systems, as a fire retardant, in the manufacture of potassium hydroxide and other compounds, and in the manufacture of potassium salts.

Potassium carbonate can be dissolved in water to make potassium hydroxide solution. The concentration at which this happens depends on both the concentration of the solution and the relative concentrations of KOH and CO32-. When equal concentrations are present, then about 35% by mass of KOH will dissolve in 100% H2O at 25 degrees Celsius (77 degrees Fahrenheit).

How much potassium carbonate to use?

The answer depends on the type of potassium carbonate you use and the concentration of your solution.

Potassium carbonate is a salt and can be used as such. Most sources, however, refer to it as a base. The reason for this is that it is used in solution with other chemicals.

When working with solutions, acids and bases must be kept separate from each other because they will react together if they come into contact. This reaction can cause dangerous chemical reactions or explosions if the concentrations are not correct.

When using potassium carbonate to make solutions, you have to account for its interaction with other chemicals involved in the process — primarily sodium hydroxide (NaOH) or ammonium hydroxide (NH4OH).

How to clean potassium carbonate?

There are many methods to clean potassium carbonate. First, use an acid such as vinegar or lemon juice, and then soak the potassium carbonate in the liquid for several hours. The acid will dissolve the dirt from your potassium carbonate. After that, you can wipe it with a towel.

Another way is to use water and soap to clean your potassium carbonate. Use warm water (not hot) and add a little soap into it, then mix them well until you get bubbles on the surface of the water. Now, put your potassium carbonate into this mixture, let it stay there for about 10 minutes. Finally, wash it again with warm water until all of the soap has been removed from its surface.

Is potassium carbonate ionic or covalent?

Potassium carbonate is an ionic compound. It’s made up of positively charged potassium ions and negatively charged carbonate ions. Ionic compounds are held together by electrostatic attraction between oppositely charged ions, so they don’t have any covalent bonds between them.

Covalent bonds are formed when atoms share electrons with each other to form a chemical bond. In ionic compounds, there aren’t any shared electrons — instead, the ions are held together by electrostatic attraction.

Is potassium carbonate acidic or basic?

Potassium carbonate is an inorganic chemical compound that reacts with acids to produce carbon dioxide gas. It is also known as potash and can be used as a leavening agent in baking. It is an ingredient in some lye-based drain cleaners, but it will not work on clogged drains unless it is mixed with other ingredients.

Potassium carbonate is one of the most common chemicals used in industry today because it has many practical applications. For example, it can be used as a neutralizing agent in the manufacturing of glass, detergents and photographic chemicals. It can also be used to soften water.

Where to buy potassium carbonate?

There are many places you can buy potassium carbonate. You can buy it from a chemical supplier, or you can find it at a local store.

You can find potassium carbonate in stores and online. For example, Amazon sells it for about $20 for a pound of the powder. Other websites also sell this product for about the same price. The prices will vary depending on the amount of potassium carbonate that you will need.

You can buy potassium carbonate powder at your local hardware store. This is a fine white powder that is used as an ingredient in many different recipes such as soap making and soap scum removal products.


Potassium carbonate (E501i) is very widely used in commercial food production because of its many attributes. A waxy, organic substance, potassium carbonate was discovered centuries ago. It was initially used as a salt substitute. Since then, it has been recognized for its ability to combine with other substances to create other useful products.

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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