Compendium of the most significant studies with reference to properties, intake, effects.

Quintero M, Velásquez S, Zapata J, López C, Cisneros-Zevallos L. Assessment of Concentrated Liquid Coffee Acceptance during Storage: Sensory and Physicochemical Perspective. Molecules. 2021 Jun 10;26(12):3545. doi: 10.3390/molecules26123545.

Abstract. Concentrated liquid coffees (CLCs) refer to stored extracts stable at environmental temperature, used as ingredients in the retail market. Their low chemical stability affects the sensory profile. This study was performed in two CLCs, one without additives (BIB) and another with a mix of sodium benzoate and potassium sorbate additives (SD), stored at 25 °C for one year.

Pérez-Prior MT, Manso JA, García-Santos Mdel P, Calle E, Casado J. Alkylating potential of potassium sorbate. J Agric Food Chem. 2005 Dec 28;53(26):10244-7. doi: 10.1021/jf052152p.

Abstract. A kinetic study of the alkylating potential of potassium sorbate (S)-a food preservative used worldwide-in 7:3 water/dioxane medium was performed. 

Diblan S, Gökkaya Erdem B, Kaya S. Sorption, diffusivity, permeability and mechanical properties of chitosan, potassium sorbate, or nisin incorporated active polymer films. J Food Sci Technol. 2020 Oct;57(10):3708-3719. doi: 10.1007/s13197-020-04403-8.

Abstract.  The active multilayer packaging films were formed from low-density polyethylene (LDPE) and polyamide containing a 2% antimicrobial agent in one of the LDPE sides of the film (LDPE/polyamide/LDPE-2% antimicrobial agent). The antimicrobial agents used were potassium sorbate (PS-film), nisin (N-film), or chitosan (CTS-film).

Nemes D, Kovács R, Nagy F, Tóth Z, Herczegh P, Borbás A, Kelemen V, Pfliegler WP, Rebenku I, Hajdu PB, Fehér P, Ujhelyi Z, Fenyvesi F, Váradi J, Vecsernyés M, Bácskay I. Comparative biocompatibility and antimicrobial studies of sorbic acid derivates. Eur J Pharm Sci. 2020 Feb 15;143:105162. doi: 10.1016/j.ejps.2019.105162.

Abstract. We aimed to test whether the esters of sorbic acid are capable to extend the antimicrobial spectrum of the original molecule while maintaining its advantageous biocompatibility profile. A comparative biocompatibility study of different derivatives (sorbic acid, potassium sorbate, isopropyl sorbate and ethyl sorbate) was carried out. 

Gaworski CL, Lemus-Olalde R, Carmines EL. Toxicological evaluation of potassium sorbate added to cigarette tobacco. Food Chem Toxicol. 2008 Jan;46(1):339-51. doi: 10.1016/j.fct.2007.08.012.

Abstract. To evaluate the effect of PS addition, neat material pyrolysis studies, smoke chemistry and biological activity studies (bacterial mutagenicity, cytotoxicity, in vivo micronucleus, and 90-day nose-only rat inhalation) with mainstream smoke, or mainstream smoke preparations from cigarettes containing various measured levels of PS (0%, 0.15%, 1.6%, and 3.7%) were performed.

Carstens CK, Salazar JK, Bathija VM, Narula SS, Wang P, Tortorello ML. Control of Listeria monocytogenes in Caramel Apples by Use of Sticks Pretreated with Potassium Sorbate. J Food Prot. 2018 Dec;81(12):1921-1928. doi: 10.4315/0362-028X.JFP-18-175.

Abstract. This study aimed to assess the effectiveness of chemical preservatives as pretreatments for the wooden stick component to reduce L. monocytogenes loads in stem end-inoculated caramel apples during storage.

Fodil S, Delgado J, Varvaro L, Yaseen T, Rodríguez A. Effect of potassium sorbate (E-202) and the antifungal PgAFP protein on Aspergillus carbonarius growth and ochratoxin A production in raisin simulating media. J Sci Food Agric. 2018 Dec;98(15):5785-5794. doi: 10.1002/jsfa.9128.

Abstract. A comparison was made between the effects of the antifungal protein PgAFP and potassium sorbate (E-202) on the growth of Aspergillus carbonarius, biosynthetic- and stress-related gene expression and its OTA production at two water activity (aw ) levels, 0.95 and 0.93 aw .

 Guynot ME, Marín S, Sanchis V, Ramos AJ. An attempt to optimize potassium sorbate use to preserve low pH (4.5-5.5) intermediate moisture bakery products by modelling Eurotium spp., Aspergillus spp. and Penicillium corylophilum growth. Int J Food Microbiol. 2005 May 25;101(2):169-77. doi: 10.1016/j.ijfoodmicro.2004.11.002. 

Abstract. Mould growth was modelled on fermented bakery product analogues (FBPA) of two different pH (4.5 and 5.5), different water activity (a(w)) levels (0.80-0.90) and potassium sorbate concentrations (0-0.3%) by using seven moulds commonly causing spoilage of bakery products (Eurotium spp., Aspergillus spp. and Penicillium corylophilum). 

Molaei S, Soleimani A, Rabiei V, Razavi F. Impact of chitosan in combination with potassium sorbate treatment on chilling injury and quality attributes of pomegranate fruit during cold storage. J Food Biochem. 2021 Apr;45(4):e13633. doi: 10.1111/jfbc.13633.

Abstract. The impact of chitosan (CH) and potassium sorbate (PS) on quality attributes of pomegranate fruits (cv. Malas e Saveh) was evaluated during 90 days of storage at 4°C and 85%-90% relative humidity.

Potassium sorbate is the potassium salt of sorbic acid and is produced by the reaction of sorbic acid with an equimolar portion of potassium hydroxide. 

Name breakdown and function of the components

• Potassium - Refers to the potassium element.
• Sorbate - Refers to the salt or ester of sorbic acid.

Description and function of the raw materials used in production

• Sorbic acid - A natural organic acid found in some berries, but most commercial sorbic acid is produced synthetically.
• Potassium hydroxide (or potassium carbonate) - Used to neutralize sorbic acid and form the potassium salt.

Summary of the industrial synthesis process step by step

• Neutralization - Sorbic acid is neutralized with potassium hydroxide or potassium carbonate to form potassium sorbate and water.
• Crystallization - The resulting solution is cooled to form crystals of potassium sorbate.
• Purification - The crystals are filtered, washed, and dried to obtain pure potassium sorbate.

It occurs as a white crystalline powder or white granules. It has good heat resistance and very good solubility in water.

What it is for and where

Potassium sorbate is known for its preservative properties and is commonly used as a preservative in foods, cosmetics, and personal care products to prevent the growth of molds and yeasts.

Food

It is a preservative, antibacterial widely used in industry as it is considered safe and reliable. It is labelled with the number E202 in the list of European additives as a preservative.

In the food sector it increases the shelf life of food and reduces the risk of bacteria (1). It has the positive characteristic of not altering the taste or colour of foods such as dried meat and dried fruit. It is mainly used in foods that are stored at room temperature or precooked, such as canned fruit and vegetables, canned fish, dried meat and desserts. It acts against moulds and is therefore often included in cheese, yoghurt, ice cream, dairy products in general, syrups and jams.

The wine industry uses it because it prevents yeast from continuing to ferment in bottles and to prevent wine from losing its flavour. 

In maize processing it is used to reduce emissions of dangerous volatile organic compounds, such as methanol, ethanol, methyl acetate, ethyl acetate and 1-propanol, preventing these gases from polluting the environment and damaging health (2).

Cosmetics

Used in detergents, shampoos, creams and body and face products to prevent the formation of mould and prolong the life of products.

It is a restricted (V/4) ingredient as a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009.

Fragrance. It plays a decisive and important role in the formulation of cosmetic products as it provides the possibility of enhancing, masking or adding fragrance to the final product, increasing its marketability.  The consumer always expects to find a pleasant or distinctive scent in a cosmetic product.

Preservative. Any product containing organic, inorganic compounds, water, needs to be preserved from microbial contamination. Preservatives act against the development of harmful microorganisms and against oxidation of the product.

Also used in various sectors such as:

• Rubber coatings
• Automotive industry
• Detergents
• Resins (as unsaturated acid)

Commercial applications

Food industry: Used as a preservative in many food products to prevent the growth of mold, yeast, and bacteria. It's often found in products like jams, jellies, wines, and baked goods.

Cosmetic and Skincare Products: Acts as a preservative in creams, lotions, and other skincare items.

Pharmaceutical: Might be used as a preservative in certain drug formulations.

Other Uses: Can also be used in some pet care products and certain industrial applications.

Properties

Preservative: Effective against the growth of mold and yeast.

Water-soluble: Dissolves easily in water, making it easy to incorporate into various products.

Low toxicity profile: It's generally recognized as safe (GRAS) for use in food and cosmetics at recommended concentrations.

Compendium of the most significant studies with reference to properties, intake, effects.

Potassium sorbate studies

Typical optimal commercial product characteristics Potassium sorbate

Appearance	White to light yellow crystalline powder or white granules.
Boiling Point	233ºC at 760 mmHg
Melting Point	270°C
Density	1,361 g/cm3
Acidity	≤ 1.0 %
Flash Point	139.9ºC
Alkalinity	≤ 1.0 %
PSA	40.13000
Water Solubility	58.2 g/100 mL (20ºC)
Formaldehyde	≤ 0.1 %
Chloride as Cl, %	≤ 0.018
Pb	≤ 10 mg/kg
Arsenic	≤ 3 mg/kg
Ash	Free
Loss on Drying	≤ 1.0 %
Safety

• Molecular Formula : C₆H₇KO₂
• Molecular Weight : 150.22
• Exact Mass   150.008316
• CAS : 24634-61-5
• UNII    1VPU26JZZ4
• EC Number   246-376-1    590-00-1
• DSSTox Substance ID DTXSID7027835
• IUPAC  potassium;(2E,4E)-hexa-2,4-dienoate
• InChI=1S/C6H8O2.K/c1-2-3-4-5-6(7)8;/h2-5H,1H3,(H,7,8);/q;+1/p-1/b3-2+,5-4+;  
• InChl Key      CHHHXKFHOYLYRE-STWYSWDKSA-M
• SMILES   CC=CC=CC(=O)[O-].[K+]
• MDL number  MFCD00016546
• PubChem Substance ID    329823274
• ChEBI  77868
• FEMA    2921
• Beilstein    5357554
• NACRES   NA,24
• RTECS   WG2170000
• HS   2916190090

Synonyms:

• Sorbic acid potassium salt
• Acid, Propenylacrylic
• Acid, Hexadienoic
• trans,trans-2,4-Hexadienoic acid potassium salt

References________________________________________________________________________

(1) Alagöz S, Türkyılmaz M, Tağı Ş, Özkan M. Effects of different sorbic acid and moisture levels on chemical and microbial qualities of sun-dried apricots during storage. Food Chem. 2015 May 1;174:356-64. doi: 10.1016/j.foodchem.2014.11.075.

(2) Hafner SD, Franco RB, Kung L Jr, Rotz CA, Mitloehner F. Potassium sorbate reduces production of ethanol and 2 esters in corn silage. J Dairy Sci. 2014 Dec;97(12):7870-8. doi: 10.3168/jds.2014-8537.