Preservative

Last updated

A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or by undesirable chemical changes. In general, preservation is implemented in two modes, chemical and physical. Chemical preservation entails adding chemical compounds to the product. Physical preservation entails processes such as refrigeration or drying. [1] Preservative food additives reduce the risk of foodborne infections, decrease microbial spoilage, and preserve fresh attributes and nutritional quality. Some physical techniques for food preservation include dehydration, UV-C radiation, freeze-drying, and refrigeration. Chemical preservation and physical preservation techniques are sometimes combined.

Contents

Food preservation

Preservatives have been used since prehistoric times. Smoked meat for example has phenols and other chemicals that delay spoilage. The preservation of foods has evolved greatly over the centuries and has been instrumental in increasing food security. The use of preservatives other than traditional oils, salts, paints, [ clarification needed ] etc. in food began in the late 19th century, but was not widespread until the 20th century. [2]

The use of food preservatives varies greatly depending on the country. Many developing countries that do not have strong governments to regulate food additives face either harmful levels of preservatives in foods or a complete avoidance of foods that are considered unnatural or foreign. These countries have also proven useful in case studies surrounding chemical preservatives, as they have been only recently introduced. [3] In urban slums of highly populated countries, the knowledge about contents of food tends to be extremely low, despite consumption of these imported foods. [4]

Antimicrobial preservatives

Antimicrobial preservatives prevent degradation by bacteria. This method is the most traditional and ancient type of preserving—ancient methods such as pickling and adding honey prevent microorganism growth by modifying the pH level. The most commonly used antimicrobial preservative is lactic acid. Common antimicrobial preservatives are presented in the table. [5] [6] [7] Nitrates and nitrites are also antimicrobial. [8] The detailed mechanism of these chemical compounds range from inhibiting growth of the bacteria to the inhibition of specific enzymes.

E number chemical compoundcomment
E200 – E203 sorbic acid, sodium sorbate and sorbatescommon for cheese, wine, baked goods, personal care products
E210 – E213 benzoic acid and benzoates used in acidic foods such as jams, salad dressing, juices, pickles, carbonated drinks, soy sauce
E214 – E219 parabens stable at a broad pH range
E220 – E228 sulfur dioxide and sulfites common for fruits, wine
E249 – E250 nitrites speed up the curing of meat and also impart an attractive colour, no effect on botulism bacteria [9] [10]
E251 – E252 nitrates used in meats
E270 lactic acid -
E280 – E283 propionic acid and propionates baked goods
E338 phosphoric acid used in some jams, preserves and carbonated drinks; also used for acidification and for flavouring.

Antioxidants

The free radical pathway for the first phase of the oxidative rancidification of fats. This process is slowed by antioxidants. Lipid peroxidation.svg
The free radical pathway for the first phase of the oxidative rancidification of fats. This process is slowed by antioxidants.

The oxidation process spoils most food, especially those with a high fat content. Fats quickly turn rancid when exposed to oxygen. Antioxidants prevent or inhibit the oxidation process. The most common antioxidant additives are ascorbic acid (vitamin C) and ascorbates. [11] Thus, antioxidants are commonly added to oils, cheese, and chips. [5] Other antioxidants include the phenol derivatives BHA, BHT, TBHQ and propyl gallate. These agents suppress the formation of hydroperoxides. [6]

E numberchemical compoundcomment
E300-304 ascorbic acid, sodium ascorbate cheese, chips
E321 butylated hydroxytoluene, butylated hydroxyanisole also used in food packaging
E310-312 gallic acid and sodium gallateoxygen scavenger
E220 – E227 sulfur dioxide and sulfites beverages, wine
E306 – E309 tocopherols vitamin E activity

A variety of agents are added to sequester (deactivate) metal ions that otherwise catalyze the oxidation of fats. Common sequestering agents are disodium EDTA, citric acid (and citrates), tartaric acid, and lecithin. [1]

Nonsynthetic compounds for food preservation

Citric and ascorbic acids target enzymes that degrade fruits and vegetables, e.g., mono/polyphenol oxidase which turns surfaces of cut apples and potatoes brown. Ascorbic acid and tocopherol, which are vitamins, are common preservatives. Smoking entails exposing food to a variety of phenols, which are antioxidants. Natural preservatives include rosemary and oregano extract, [12] hops, salt, sugar, vinegar, alcohol, diatomaceous earth and castor oil.

Traditional preservatives, such as sodium benzoate have raised health concerns in the past. Benzoate was shown in a study to cause hypersensitivity in some asthma sufferers. This has caused reexamination of natural preservatives which occur in vegetables. [13]

Public awareness of food preservation

Public awareness of food preservatives is uneven. [14] Americans have a perception that food-borne illnesses happen more often in other countries. This may be true, but the occurrence of illnesses, hospitalizations, and deaths are still high. It is estimated by the Centers for Disease Control (CDC) that each year there are 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths linked to food-borne illness. [15]

Food suppliers are facing difficulties with regards to the safety and quality of their products as a result of the rising demand for ready-to-eat fresh food products. Artificial preservatives meet some of these challenges by preserving freshness for longer periods of time, but these preservatives can cause negative side-effects as well.

Preservation of other products

Water-based home and personal care products use broad-spectrum preservatives, such as isothiazolinones and formaldehyde releasers, which may cause sensitization, leading to allergic skin. [19]

SubstanceUse
parabens personal care products
isothiazolinones (MIT, CMIT, BIT)not for food: home and personal care products, paints/coatings
formaldehyde releasers (DMDM hydantoin)not for food: home and personal care products

See also

Related Research Articles

<span class="mw-page-title-main">Chemistry of ascorbic acid</span> Chemical compound

Ascorbic acid is an organic compound with formula C
6
H
8
O
6
, originally called hexuronic acid. It is a white solid, but impure samples can appear yellowish. It dissolves freely in water to give mildly acidic solutions. It is a mild reducing agent.

Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants are frequently added to industrial products, such as polymers, fuels, and lubricants, to extend their usable lifetimes. Foods are also treated with antioxidants to forestall spoilage, in particular the rancidification of oils and fats. In cells, antioxidants such as glutathione, mycothiol, or bacillithiol, and enzyme systems like superoxide dismutase, can prevent damage from oxidative stress.

<span class="mw-page-title-main">Benzoic acid</span> Organic compound (C6H5COOH)

Benzoic acid is a white solid organic compound with the formula C6H5COOH, whose structure consists of a benzene ring with a carboxyl substituent. The benzoyl group is often abbreviated "Bz", thus benzoic acid is also denoted as BzOH, since the benzoyl group has the formula –C6H5CO. It is the simplest aromatic carboxylic acid. The name is derived from gum benzoin, which was for a long time its only source.

<span class="mw-page-title-main">Food preservation</span> Inhibition of microbial growth in food

Food preservation includes processes that make food more resistant to microorganism growth and slow the oxidation of fats. This slows down the decomposition and rancidification process. Food preservation may also include processes that inhibit visual deterioration, such as the enzymatic browning reaction in apples after they are cut during food preparation. By preserving food, food waste can be reduced, which is an important way to decrease production costs and increase the efficiency of food systems, improve food security and nutrition and contribute towards environmental sustainability. For instance, it can reduce the environmental impact of food production.

<span class="mw-page-title-main">Butylated hydroxytoluene</span> Chemical compound

Butylated hydroxytoluene (BHT), also known as dibutylhydroxytoluene, is a lipophilic organic compound, chemically a derivative of phenol, that is useful for its antioxidant properties. BHT is widely used to prevent free radical-mediated oxidation in fluids and other materials, and the regulations overseen by the U.S. F.D.A.—which considers BHT to be "generally recognized as safe"—allow small amounts to be added to foods. Despite this, and the earlier determination by the National Cancer Institute that BHT was noncarcinogenic in an animal model, societal concerns over its broad use have been expressed. BHT has also been postulated as an antiviral drug, but as of December 2022, use of BHT as a drug is not supported by the scientific literature and it has not been approved by any drug regulatory agency for use as an antiviral.

Rancidification is the process of complete or incomplete autoxidation or hydrolysis of fats and oils when exposed to air, light, moisture, or bacterial action, producing short-chain aldehydes, ketones and free fatty acids.

<span class="mw-page-title-main">Sodium nitrite</span> Chemical compound

Sodium nitrite is an inorganic compound with the chemical formula NaNO2. It is a white to slightly yellowish crystalline powder that is very soluble in water and is hygroscopic. From an industrial perspective, it is the most important nitrite salt. It is a precursor to a variety of organic compounds, such as pharmaceuticals, dyes, and pesticides, but it is probably best known as a food additive used in processed meats and in fish products.

<span class="mw-page-title-main">Potassium benzoate</span> Chemical compound

Potassium benzoate (E212), the potassium salt of benzoic acid, is a food preservative that inhibits the growth of mold, yeast and some bacteria. It works best in low-pH products, below 4.5, where it exists as benzoic acid.

<span class="mw-page-title-main">Sodium benzoate</span> Chemical compound

Sodium benzoate also known as benzoate of soda is the sodium salt of benzoic acid, widely used as a food preservative (with an E number of E211) and a pickling agent. It appears as a white crystalline chemical with the formula C6H5COONa.

An antimicrobial is an agent that kills microorganisms (microbicide) or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals are used against fungi. They can also be classified according to their function. The use of antimicrobial medicines to treat infection is known as antimicrobial chemotherapy, while the use of antimicrobial medicines to prevent infection is known as antimicrobial prophylaxis.

<span class="mw-page-title-main">Sorbic acid</span> Organic compound (CH3(CH)4COOH)

Sorbic acid, or 2,4-hexadienoic acid, is a natural organic compound used as a food preservative. It has the chemical formula CH3(CH)4CO2H and the structure H3C−CH=CH−CH=CH−C(=O)OH. It is a colourless solid that is slightly soluble in water and sublimes readily. It was first isolated from the unripe berries of the Sorbus aucuparia, hence its name.

<span class="mw-page-title-main">Sodium erythorbate</span> Chemical compound

Sodium erythorbate (C6H7NaO6) is a food additive used predominantly in meats, poultry, and soft drinks. Chemically, it is the sodium salt of erythorbic acid. When used in processed meat such as hot dogs and beef sticks, it increases the rate at which nitrite reduces to nitric oxide, thus facilitating a faster cure and retaining the pink coloring. As an antioxidant structurally related to vitamin C, it helps improve flavor stability and prevents the formation of carcinogenic nitrosamines. When used as a food additive, its E number is E316. The use of erythorbic acid and sodium erythorbate as a food preservative has increased greatly since the U.S. Food and Drug Administration banned the use of sulfites as preservatives in foods intended to be eaten fresh (such as ingredients for fresh salads) and as food processors have responded to the fact that some people are allergic to sulfites. It can also be found in bologna, and is occasionally used in beverages, baked goods, and potato salad. Sodium erythorbate is produced from sugars derived from different sources, such as beets, sugarcane, and corn. Sodium erythorbate is usually produced via a fermentation process from D-glucose by Pseudomonas fluorescens bacteria. Most syntheses proceed through the 2-keto-D-gluconic acid intermediate. An urban myth claims that sodium erythorbate is made from ground earthworms; however, there is no truth to the myth. It is thought that the origin of the legend comes from the similarity of the chemical name to the words earthworm and bait.

<span class="mw-page-title-main">Potassium sorbate</span> Chemical compound

Potassium sorbate is the potassium salt of sorbic acid, chemical formula CH3CH=CH−CH=CH−CO2K. It is a white salt that is very soluble in water (58.2% at 20 °C). It is primarily used as a food preservative (E number 202). Potassium sorbate is effective in a variety of applications including food, wine, and personal-care products. While sorbic acid occurs naturally in rowan and hippophae berries, virtually all of the world's supply of sorbic acid, from which potassium sorbate is derived, is manufactured synthetically.

<span class="mw-page-title-main">Mineral ascorbates</span>

Mineral ascorbates are a group of salts of ascorbic acid. They are composed of a mineral cation bonded to ascorbate.

Calcium propanoate or calcium propionate has the formula Ca(C2H5COO)2. It is the calcium salt of propanoic acid.

<span class="mw-page-title-main">Cured fish</span> Fish subjected to fermentation, pickling or smoking

Cured fish is fish which has been cured by subjecting it to fermentation, pickling, smoking, or some combination of these before it is eaten. These food preservation processes can include adding salt, nitrates, nitrite or sugar, can involve smoking and flavoring the fish, and may include cooking it. The earliest form of curing fish was dehydration. Other methods, such as smoking fish or salt-curing also go back for thousands of years. The term "cure" is derived from the Latin curare, meaning to take care of. It was first recorded in reference to fish in 1743.

Warmed-over flavor is an unpleasant characteristic usually associated with meat which has been cooked and then refrigerated. The deterioration of meat flavor is most noticeable upon reheating. As cooking and subsequent refrigeration is the case with most convenience foods containing meat, it is a significant challenge to the processed food industry. The flavor is variously described as "rancid," "stale," and like "cardboard," and even compared to "damp dog hair." Warmed-over flavor is caused by the oxidative decomposition of lipids in the meat into chemicals which have an unpleasant taste or odor. This decomposition process begins after cooking or processing and is aided by the release of naturally occurring iron in the meat.

<span class="mw-page-title-main">Biopreservation</span>

Biopreservation is the use of natural or controlled microbiota or antimicrobials as a way of preserving food and extending its shelf life. The biopreservation of food, especially utilizing lactic acid bacteria (LAB) that are inhibitory to food spoilage microbes, has been practiced since early ages, at first unconsciously but eventually with an increasingly robust scientific foundation. Beneficial bacteria or the fermentation products produced by these bacteria are used in biopreservation to control spoilage and render pathogens inactive in food. There are a various modes of action through which microorganisms can interfere with the growth of others such as organic acid production, resulting in a reduction of pH and the antimicrobial activity of the un-dissociated acid molecules, a wide variety of small inhibitory molecules including hydrogen peroxide, etc. It is a benign ecological approach which is gaining increasing attention.

<span class="mw-page-title-main">Wine preservatives</span> Food preservation

Wine preservatives are used to preserve the quality and shelf life of bottled wine without affecting its taste. Specifically, they are used to prevent oxidation and bacterial spoilage by inhibiting microbial activity.

References

  1. 1 2 Erich Lück and Gert-Wolfhard von Rymon Lipinski "Foods, 3. Food Additives" in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. doi : 10.1002/14356007.a11_561
  2. Evans, G., de Challemaison, B., & Cox, D. N. (2010). "Consumers' ratings of the natural and unnatural qualities of foods". Appetite. 54 (3): 557–563. doi:10.1016/j.appet.2010.02.014. PMID   20197074. S2CID   41078790.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. Ashagrie, Z. Z., & Abate, D. D. (2012). IMPROVEMENT OF INJERA SHELF LIFE THROUGH THE USE OF CHEMICAL PRESERVATIVES. African Journal of Food, Agriculture, Nutrition & Development, 12(5), 6409-6423.
  4. Kumar, H., Jha, A., Taneja, K. K., Kabra, K., & Sadiq, H. M. (2013). A STUDY ON CONSUMER AWARENESS, SAFETY PERCEPTIONS & PRACTICES ABOUT FOOD PRESERVATIVES AND FLAVOURING AGENTS USED IN PACKED /CANNED FOODS FROM SOUTH INDIA. National Journal of Community Medicine, 4(3), 402-406.
  5. 1 2 Msagati, Titus A. M. (2012). The Chemistry of Food Additives and Preservatives. Retrieved from http://www.eblib.com Archived 2016-02-07 at the Wayback Machine
  6. 1 2 Dalton, Louisa (November 2002). "Food Preservatives". Chemical and Engineering News. 80 (45): 40. doi:10.1021/cen-v080n045.p040. Archived from the original on 5 April 2019. Retrieved 9 February 2012.
  7. "Using Preservatives". Archived from the original on 28 March 2019. Retrieved 9 February 2012.
  8. Shaw, Ian C. (2012). Food Safety : The Science of Keeping Food Safe. Retrieved from http://www.eblib.com Archived 2016-02-07 at the Wayback Machine (306- 334)
  9. Wilson, Bee (2018-03-01). "Yes, bacon really is killing us". The Guardian. London. ISSN   0261-3077. Archived from the original on 2021-02-10. Retrieved 2021-02-14. In trade journals of the 1960s, the firms who sold nitrite powders to ham-makers spoke quite openly about how the main advantage was to increase profit margins by speeding up production.
  10. Doward, Jamie (2019-03-23). "Revealed: no need to add cancer-risk nitrites to ham". The Observer. London. Archived from the original on 2021-01-26. Retrieved 2021-02-14. The results show that there is no change in levels of inoculated C. botulinum over the curing process, which implies that the action of nitrite during curing is not toxic to C. botulinum spores at levels of 150ppm [parts per million] ingoing nitrite and below.
  11. 1 2 (Bhat, Rajeev; Alias, Abd Karim; Paliyath, Gopinadham (2011). Progress in Food Preservation. Retrieved from http://www.eblib.com Archived 2016-02-07 at the Wayback Machine
  12. Riva Pomerantz (Nov 15, 2017). "KOSHER IN THE LAB". Ami . No. 342. p. 88.
  13. P'EREZ-D'IAZ, I.M; MCFEETERS, R.F (May 2010). "Preservation of Acidified Cucumbers with a Natural Preservative Combination of Fumaric Acid and Allyl Isothiocyanate that Target Lactic Acid Bacteria and Yeasts". Journal of Food Science. 75 (4): M204–M208. doi:10.1111/j.1750-3841.2010.01587.x. PMID   20546411. Archived from the original on 2021-02-19. Retrieved 2018-12-29.
  14. Kumar, H. N. Harsha; Jha, Anshu Kumar; Taneja, Khushboo K.; Kabra, Krishan; Sadiq, Hafeez M. (2013). A Study On Consumer Awareness, Safety Perceptions & Practices about Food Preservatives and Flavouring Agents used in Packed/Canned Foods from South India. National Journal of Community Medicine, 4(3), 402.
  15. Theron, M. M. & Lues, J. F. (2007). Organic acids and meat preservation: A review. Food Reviews International, 23, 141-158.
  16. Field, Simon Quellen (2008). Why There's Antifreeze in Your Toothpaste: The Chemistry of Household Ingredients. Chicago: Chicago Review Press.
  17. 1 2 Antinoro, L. (2008). EN Rates 12 Common Food Additives As Safe Or Sorry Ingredients. (Cover story). Environmental Nutrition, 31(5), 1-4.
  18. Barrett, J. R. (2007). "Hyperactive Ingredients?". Environmental Health Perspectives. 115 (12): A578. doi:10.1289/ehp.115-a578. PMC   2137120 . PMID   18087571.
  19. "The search is on for new cosmetic preservatives". Chemical & Engineering News. Archived from the original on 2021-10-25. Retrieved 2021-10-25.