Components that contribute to preservative action in various food, pharmaceutical, and cosmetic sectors, a few examples:

• Sorbic acid and its salts (potassium sorbate, calcium sorbate). These preservatives are effective against molds, yeasts, and some bacteria, and are commonly used in food products such as cheeses, beverages, and baked goods (1).
• Propionic acid and propionates (sodium propionate, calcium propionate). Common preservatives in bread and other baked goods to prevent mold growth (2).
• Citric acid. Besides being an acidity regulator, citric acid has preservative properties and is used in beverages, canned goods, and baked products.
• Ascorbic acid (vitamin C) and sodium ascorbate. In addition to their antioxidant properties, these compounds are used as preservatives in a variety of food products, including baked goods, beverages, and processed meats.
• Lactic acid. Used in products like pickles, baked goods, and some dairy products for its antimicrobial properties (3).
• Benzoates (sodium benzoate, potassium benzoate). Primarily used in acidic products like soft drinks, fruit juices, sauces, and condiments, benzoates are effective against yeasts, molds, and some bacteria.

Several components can contribute to or exacerbate the growth of harmful microorganisms and deterioration in food, cosmetic, and pharmaceutical products. These include:

• Moisture and water. Water is essential for microbial growth, and high humidity can accelerate the proliferation of bacteria and molds.
• Nutrients. Sugars, proteins, and fats in products can provide a source of nourishment for microorganisms.
• Inadequate pH. A neutral or slightly acidic pH favors the growth of many microorganisms.
• Oxygen. Some microorganisms, such as aerobic bacteria, require oxygen to grow.
• Inadequate temperatures. High temperatures or temperature fluctuations can accelerate microbial growth.
• Cross-contamination. The use of contaminated tools or packaging can introduce microorganisms into otherwise sterile products.
• Insufficient or ineffective preservatives. The lack of adequate preservatives or their degradation over time can allow microbial growth.
• Light and radiation. Light, particularly UV light, can degrade some components, making the product more susceptible to microbial growth.

References_____________________________________________________________________

(1) Holyoak CD, Stratford M, McMullin Z, Cole MB, Crimmins K, Brown AJ, Coote PJ. Activity of the plasma membrane H(+)-ATPase and optimal glycolytic flux are required for rapid adaptation and growth of Saccharomyces cerevisiae in the presence of the weak-acid preservative sorbic acid. Appl Environ Microbiol. 1996 Sep;62(9):3158-64. doi: 10.1128/aem.62.9.3158-3164.1996. PMID: 8795204; PMCID: PMC168110.

Abstract. The weak acid sorbic acid transiently inhibited the growth of Saccharomyces cerevisiae in media at low pH. During a lag period, the length of which depended on the severity of this weak-acid stress, yeast cells appeared to adapt to this stress, eventually recovering and growing normally. This adaptation to weak-acid stress was not due to metabolism and removal of the sorbic acid. A pma1-205 mutant, with about half the normal membrane H+-ATPase activity, was shown to be more sensitive to sorbic acid than its parent. Sorbic acid appeared to stimulate plasma membrane H+-ATPase activity in both PMA1 and pma1-205. Consistent with this, cellular ATP levels showed drastic reductions, the extent of which depended on the severity of weak-acid stress. The weak acid did not appear to affect the synthesis of ATP because CO2 production and O2 consumption were not affected significantly in PMA1 and pma1-205 cells. However, a glycolytic mutant, with about one-third the normal pyruvate kinase and phosphofructokinase activity and hence a reduced capacity to generate ATP, was more sensitive to sorbic acid than its isogenic parent. These data are consistent with the idea that adaptation by yeast cells to sorbic acid is dependent on (i) the restoration of internal pH via the export of protons by the membrane H+-ATPase in an energy-demanding process and (ii) the generation of sufficient ATP to drive this process and still allow growth.

(2) Yun SS, Kim J, Lee SJ, So JS, Lee MY, Lee G, Lim HS, Kim M. Naturally occurring benzoic, sorbic, and propionic acid in vegetables. Food Addit Contam Part B Surveill. 2019 Sep;12(3):167-174. doi: 10.1080/19393210.2019.1579760. Epub 2019 Feb 22. PMID: 30793667.

Abstract. Benzoic, sorbic and propionic acid are used as preservatives in foods and can also be naturally present in processed foods. The levels of preservatives in 939 vegetables were determined. Benzoic and sorbic acid were analysed by high-performance liquid chromatography with a diode-array detector and further confirmed by liquid chromatography-tandem mass spectrometry, whereas propionic acid was analysed using a gas chromatography-flame ionization detector and further confirmed by gas chromatography-mass spectrometry. Benzoic and propionic acid were found in 10.9% and 36.2%, respectively, of the samples. In contrast, sorbic acid was not found in any of the samples. The highest amounts of benzoic and propionic acid were found in perilla leaves (0.33-298 mg kg-1) and ginseng (<LOD-32.8 mg kg-1), respectively. The background concentration ranges of naturally occurring preservatives in vegetables determined in this study could be used for inspection services of standard criteria to address consumer complaints or trade disputes.

(3) Zapaśnik A, Sokołowska B, Bryła M. Role of Lactic Acid Bacteria in Food Preservation and Safety. Foods. 2022 Apr 28;11(9):1283. doi: 10.3390/foods11091283. 

Abstract. Fermentation of various food stuffs by lactic acid bacteria is one of the oldest forms of food biopreservation. Bacterial antagonism has been recognized for over a century, but in recent years, this phenomenon has received more scientific attention, particularly in the use of various strains of lactic acid bacteria (LAB). Certain strains of LAB demonstrated antimicrobial activity against foodborne pathogens, including bacteria, yeast and filamentous fungi. Furthermore, in recent years, many authors proved that lactic acid bacteria have the ability to neutralize mycotoxin produced by the last group. Antimicrobial activity of lactic acid bacteria is mainly based on the production of metabolites such as lactic acid, organic acids, hydroperoxide and bacteriocins. In addition, some research suggests other mechanisms of antimicrobial activity of LAB against pathogens as well as their toxic metabolites. These properties are very important because of the future possibility to exchange chemical and physical methods of preservation with a biological method based on the lactic acid bacteria and their metabolites. Biopreservation is defined as the extension of shelf life and the increase in food safety by use of controlled microorganisms or their metabolites. This biological method may determine the alternative for the usage of chemical preservatives. In this study, the possibilities of the use of lactic acid bacteria against foodborne pathogens is provided. Our aim is to yield knowledge about lactic acid fermentation and the activity of lactic acid bacteria against pathogenic microorganisms. In addition, we would like to introduce actual information about health aspects associated with the consumption of fermented products, including probiotics.