Antioxidants for food use

Antioxidants, when used as food additives, are molecules added to food to prevent or slow down oxidation that can occur during the transport, storage, and processing of the product.[2][11]

The oxidation of food occurs as a result of exposure to atmospheric oxygen, light, and heat. This causes the modification or destruction of specific molecules that, due to their chemical structure, are particularly sensitive to oxidative damage. As a result, there may be a reduction in organoleptic properties, such as colour, flavour, and texture, as well as in nutritional values.[3][10]

The most commonly used antioxidants are organic compounds such as phenols, aromatic amines, and aminophenols.[4]

Like other food additives, antioxidants are identified by the E-numbering system, where “E” stands for Europe, in addition to their chemical name.[8]

Antioxidants, like most food additives, are not harmful to human health when used according to specific guidelines.[6]

Contents

How do antioxidants work?

Antioxidants prevent or slow down oxidation processes.
The main antioxidant mechanisms are:

  • free radical scavenging;
  • removal of peroxides or reactive oxygen species;
  • quenching of secondary lipid oxidation products, which may produce rancid odors;
  • chelation of metals.[10]

Examples of molecules highly sensitive to oxidative damage include unsaturated fatty acids, both monounsaturated and polyunsaturated, vitamins, and various amino acids. Unsaturated fatty acids are present, in the form of triglycerides, in oils and fats used for cooking, such as olive oil, butter, or margarine. Their oxidation is part of the process that causes the rancidity of these products.[1]

Antioxidants also play an important role in preventing the formation of molecules that can potentially harm health, a function similar to that of preservatives.[9]

Natural and artificial antioxidants

Antioxidants, which chemically are reducing agents, can be of natural origin, such as vitamin C (E300) and alpha-tocopherol (E307), or artificial, such as gallates, the esters of ascorbic acid with fatty acids (E 304), erythorbic acid (E315), which is the D-isomer of vitamin C, with low vitamin activity, or tert-butylhydroquinone (E319) and butylated hydroxytoluene (E321).[7]
Skeletal formula of some antioxidants: alpha-tocopherol (E307), ascorbic acid (E300), propyl gallate (E310), tert-butylhydroquinone (E319), and butylated hydroxytoluene (E321).However, the distinction between artificial and natural occurring antioxidants is misleading since, for example, both vitamin C and tocopherols are often produced artificially, as their high demand cannot be met by natural sources alone.[7]

Examples of antioxidants

Below is an overview of some antioxidants included in the list of food additives approved in the European Union according to Regulation 1129/2011 of the European Commission, published on November 11, 2011. This list is an amendment of Annex II to Regulation (EC) No. 1333/2008 of the European Parliament, and was in turn amended in 2013.[5]

E-number Additive and derivatives
Vitamin C or ascorbic acid
E300 Ascorbic acid
E301 Sodium ascorbate
E302 Calcium ascorbate
E304 Esters of ascorbic acid with fatty acids
Tocopherols
E306 Tocopherol-rich extract
E307 Alpha-tocopherol
E308 Gamma-tocopherol
E309 Delta-tocopherol
Gallates and other antioxidants
E310 Propyl gallate
E311 Octyl gallate
E312 Dodecyl gallate
E315 Erythorbic acid
E316 Sodium erythorbate
E319 tert-Butylhydroquinone (TBHQ)
E320 Butylated hydroxyanisole (BHA)
E321 Butylated hydroxytoluene (BHT)

Health effects

The safety of antioxidants, like other food additives, is evaluated by relevant authorities, relying on the latest scientific research available during their review. Scientific evidence indicates that when antioxidants are used within established guidelines, they pose no health risks. Nonetheless, these additives undergo regular safety reassessments to ensure continued compliance with health standards.[6]

References

  1. ^ Akoh C.C., Min D.B. Food lipids: chemistry, nutrition, and biotechnology. 3th Edition. 2008. doi:10.1201/9781420046649
  2. ^ Bender D.A. Benders’ dictionary of nutrition and food technology. 8th ed. Woodhead Publishing. Oxford, 2006.
  3. ^ Belitz H.-D., Grosch W., Schieberle P. Food Chemistry. 4th Edition. Springer, 2009.
  4. ^ Britannica, The Editors of Encyclopaedia. Antioxidant. Encyclopedia Britannica, 7 Nov. 2024. Accessed 10 December 2024.
  5. ^ Commission Regulation (EU) No 1129/2011 of 11 November 2011 amending Annex II to Regulation (EC) No 1333/2008 of the European Parliament and of the Council by establishing a Union list of food additives. https://eur-lex.europa.eu/eli/reg/2011/1129/2013-11-21
  6. ^ a b EFSA Food additives: EFSA’s new guidance for applicants. Published: 18 July 2012. https://www.efsa.europa.eu/en/press/news/120718a
  7. ^ a b EUFIC. The importance of antioxidants in food. Last updated: 01 July 2004. https://www.eufic.org/en/whats-in-food/article/food-should-also-look-good-why-antioxidants-are-so-important
  8. ^ Food Standards Agency. Approved additives and E Numbers. Last updated: 23 January 2024.
  9. ^ García-García R., Searle S.S. Preservatives: food use. Encyclopedia of Food and Health. 2016:505-509. doi:10.1016/B978-0-12-384947-2.00568-7
  10. ^ a b Hui Y.H., Sherkat F. Handbook of food science, technology, and engineering – 4 volume set. 1st Edition. 2005. CRC Press. doi:10.1201/b15995
  11. ^ Wilson D.W., Nash P., Buttar H.S., Griffiths K., Singh R., De Meester F., Horiuchi R., Takahashi T. The role of food antioxidants, benefits of functional foods, and influence of feeding habits on the health of the older person: an overview. Antioxidants (Basel). 2017;6(4):81. doi:10.3390/antiox6040081

Biochemistry and metabolism