E500 (Sodium carbonate) is a chemical compound, the sodium salt of carbonic acid.

Food

Ingredient included in the list of European food additives as E500 with a leavening function.

In the list of European food additives is specified as follows:

• E500 (i) Sodium carbonate 
• E500 (ii) Sodium bicarbonate 
• E500 (iii) Sodium Sesquicarbonate

Sodium carbonate has multiple uses in the industrial sector of building materials, food industry, chemical industry with daily chemicals, metallurgy, textiles, pharmaceuticals, medicine and other sectors.

In the manufacturing process of detergents and soaps it is used as a filler and to make the product smoother. 

It is adjuvant in the production of chemical products such as sodium silicate, sodium bicarbonate and percarbonate, chromate and sodium dichromate.

The glass industry needs 0.2 tons of sodium carbonate per ton of glass because, in the glass manufacturing process it reduces the melting temperature of the sand used in glass formation and aids in the shaping and workability of glassware such as tableware, optical glass and float glass.

Sodium carbonate can reduce the corrosive effect of alkali dust on refractory materials and extend furnace life.

In the food industry it acts as a leavening, buffering and dough softening agent in baked goods and especially in cakes and pastries as well as in soy sauce, bread, amino acid production. When mixed with alkaline water and added to dough has the property of increasing elasticity and ductility. Sodium carbonate can also be used to produce MSG, Monosodium Glutamate.

In the pharmaceutical industry it is used as osmotic laxative and antacid. It is inserted into medicinal tablets as a filler, a substance used to increase the volume of the mass to be compressed to the desired volume.

In the metalworking industry, sodium carbonate is used for electrolytic coppering, electrolytic polishing of aluminum and alloys, chemical and electrochemical degreasing, chemical oxidation of aluminum, corrosion of aluminum, rust prevention between processes, electrolytic degradation, sealing after phosphating. It also serves for chromium plating and subsequent removal of chromium oxide film, copper pre-plating, steel plating and in the electrolyte plating of steel alloy.

In metallurgical industry, it is desulfurization agent in steel production and antimony smelting.

In the tanning industry it neutralizes chrome tanned leather, degreases leather, improves the alkalinity of chrome tanning bath.

Also used as a test to calibrate the acid in quantitative analysis, co-solvent analysis of silica in cement, glucose analysis in urine and blood, test for the determination of copper, lead, zinc, aluminum, sulfur. Metallographic analysis etc.

For the production of lactulose, it has proved to be effective by considerably reducing the production time (1).

It is used in the preparation and cooking of patties and hamburgers to improve their elasticity, hardness and cohesion (2).

It has been used as an efficient and inexpensive alkaline catalyst for pretreatment of corn straw and lignocellulosic biomass (3).

It is used to improve the tolerance of fruit (in this case pears) to frost damage (4).

It is an anti-inflammatory and is also used as a tooth-cleaning agent (5).

Safety

 A 2024 study warns about the risk of developing cancer with high intakes of emulsifiers, (including E440, Pectin, E471 mono- and diglycerides of fatty acids, carrageenan, E407, sodium carbonate E500) (6).  

The most relevant studies on this ingredient have been selected with a summary of their contents:

Sodium carbonate studies

• Molecular Formula: CNa₂O₃
• Molecular Weight: 105.988 g/mol
• UNII: 45P3261C7T
• CAS: 497-19-8  7542-12-3  6106-20-3  1332-57-6  1314087-39-2  1977561-09-3
• EC Number: 207-838-8  231-420-4
• PubChem Substance ID 24899762
• Beilstein Registry Number 4154566

Synonyms: 

• Disodium carbonate
• Carbonic acid sodium salt
• Sodium carbonate anhydrous
• Anhydrous soda
• CHEBI:29377
• Soda Ash
• Carbonic acid disodium salt
• Trona
• Soda Ash Light 4P
• Suprapur 6395
• Crystol carbonate
• Caswell N0 752
• Natriumkarbonat
• Bisodium carbonate
• Dynamar L 13890
• Soda
• Calcined soda
• sodiumcarbonate
• Sodium carbonate, anhydrous
• Washing soda
• Carbonic acid, disodium salt
• Solvay soda
• Soda, calcined
• Snowlite I
• Light Ash
• V Soda

References___________________________________

(1) Seo YH, Park GW, Han JI. Efficient lactulose production from cheese whey using sodium carbonate. Food Chem. 2015 Apr 15;173:1167-71. doi: 10.1016/j.foodchem.2014.10.109. 

(2) Parlak O, Zorba O, Kurt S. Modelling with response surface methodology of the effects of egg yolk, egg white and sodium carbonate on some textural properties of beef patties. J Food Sci Technol. 2014 Apr;51(4):780-4. doi: 10.1007/s13197-011-0552-4.

Abstract. This study was accomplished to determine the effects of egg yolk, egg white and sodium carbonate on textural properties of beef patties by using Central Composite Design of Response Surface Methodology. Meat patties were prepared using beef, lamb tail fat and spices. Effects of addition of egg yolk powder (0-1%), egg white powder (0-1%) and sodium carbonate (0-1%) on textural properties were studied by using a texture analyzer. The TPA and cutting force tests were measured in the samples. Effects of sodium carbonate were found to be significant (P < 0.01) on springiness, hardness and cohesiveness values of beef patties. However, effects of egg white and egg yolk on the textural parameters were not found significant (P > 0.05). The levels of sodium carbonate up to 0.72% improved the textural properties of beef patties.

(3)Kim I, Rehman MS, Han JI. Enhanced glucose yield and structural characterization of corn stover by sodium carbonate pretreatment. Bioresour Technol. 2014;152:316-20. doi: 10.1016/j.biortech.2013.10.069.

(4) D'Aquino S, Barberis A, Continella A, La Malfa S, Gentile A, Schirra M. Individual and combined effects of postharvest dip treatments with water at 50 degrees C, soy lecithin and sodium carbonate on cold stored cactus pear fruits. Commun Agric Appl Biol Sci. 2012;77(3):207-17.

Abstract. Objective of this study was to evaluate the effect of prestorage dip treatments at 20 degrees C or 50 degrees C alone or with sodium carbonate (SC) and soy lecithin (LEC), either individually or in combination, on weight losses, peel disorders, overall appearance and decay of cactus pears. Fruits were subjected to a simulated Mediterranean fruit fly (medfly) disinfestation by cold quarantine at 2 degrees C for 21 days followed by one week of shelf-life at 20 degrees C. Hot water alone was very effective in reducing peel disorders and decay both during cold storage and shelf-life. SC applied at 20 degrees C showed a weak control of decay and chilling injury, while its effectiveness significantly increased when the solution temperature was set to 50 degrees C. LEC was more effective in preserving freshness during cold storage, but after shelf-life decay incidence in fruit dipped in LEC at 20 degrees C or 50 degrees C was higher than in those dipped in water at 20 degrees C or 50 degrees C, respectively. Significant but moderate differences were detected among treatments in weight loss. After shelf-life, fruit dipped in the heated mixture of SC and LEC showed the lowest incidence of peel disorders and the highest percentage of marketable fruit, although decay incidence was slightly higher than in fruit treated with SC at 50 degrees C. SC and LEC used in combination at 50 degrees C improved fruit tolerance to chilling injury and reduced decay.

(5) Turker SB, Sener ID, Koçak A, Yilmaz S, Ozkan YK. Factors triggering the oral mucosal lesions by complete dentures. Arch Gerontol Geriatr. 2010 Jul-Aug;51(1):100-4. doi: 10.1016/j.archger.2009.09.001. 

(6) Sellem, L., Srour, B., Javaux, G., Chazelas, E., Chassaing, B., Viennois, E., ... & Touvier, M. (2024). Food additive emulsifiers and cancer risk: Results from the French prospective NutriNet-Santé cohort. Plos Medicine, 21(2), e1004338.

Abstract. Emulsifiers are widely used food additives in industrially processed foods to improve texture and enhance shelf-life. Experimental research suggests deleterious effects of emulsifiers on the intestinal microbiota and the metabolome, leading to chronic inflammation and increasing susceptibility to carcinogenesis. However, human epidemiological evidence investigating their association with cancer is nonexistent. This study aimed to assess associations between food additive emulsifiers and cancer risk in a large population-based prospective cohort. Methods and findings: This study included 92,000 adults of the French NutriNet-Santé cohort without prevalent cancer at enrolment (44.5 y [SD: 14.5], 78.8% female, 2009 to 2021). They were followed for an average of 6.7 years [SD: 2.2]. Food additive emulsifier intakes were estimated for participants who provided at least 3 repeated 24-h dietary records linked to comprehensive, brand-specific food composition databases on food additives. Multivariable Cox regressions were conducted to estimate associations between emulsifiers and cancer incidence. Overall, 2,604 incident cancer cases were diagnosed during follow-up (including 750 breast, 322 prostate, and 207 colorectal cancers). Higher intakes of mono- and diglycerides of fatty acids (FAs) (E471) were associated with higher risks of overall cancer (HR high vs. low category = 1.15; 95% CI [1.04, 1.27], p-trend = 0.01), breast cancer (HR = 1.24; 95% CI [1.03, 1.51], p-trend = 0.04), and prostate cancer (HR = 1.46; 95% CI [1.09, 1.97], p-trend = 0.02). In addition, associations with breast cancer risk were observed for higher intakes of total carrageenans (E407 and E407a) (HR = 1.32; 95% CI [1.09, 1.60], p-trend = 0.009) and carrageenan (E407) (HR = 1.28; 95% CI [1.06, 1.56], p-trend = 0.01). No association was detected between any of the emulsifiers and colorectal cancer risk. Several associations with other emulsifiers were observed but were not robust throughout sensitivity analyses. Main limitations include possible exposure measurement errors in emulsifiers intake and potential residual confounding linked to the observational design. Conclusions: In this large prospective cohort, we observed associations between higher intakes of carrageenans and mono- and diglycerides of fatty acids with overall, breast and prostate cancer risk. These results need replication in other populations. They provide new epidemiological evidence on the role of emulsifiers in cancer risk. Copyright: © 2024 Sellem et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.