- Characteristics of lactic acid: it is an organic chemical compound, occurring in L- and D- isomers, naturally formed during fermentation and in muscles.
- Physicochemical properties: lactic acid is a hygroscopic liquid, well soluble in water, having hydroxyl and carboxyl groups.
- Applications in various industries: used as a preservative in food, in cosmetics as an exfoliator and in medicine as a probiotic.
- Versatile in cosmetics and medicine: moisturizes the skin, removes dead skin, supports the balance of intestinal microflora and vaginal microflora.
What is lactic acid?
Lactic acid (lactic acid) is also known as alpha-hydroxypropanoic acid (2-hydroxypropanoic acid), is an organic chemical compound that exists in two optical isomers: L- and D-lactic acid. It is formed naturally as a byproduct of bacterial fermentation of sugar, cornstarch or dairy whey, as well as in muscles during intense exercise. It is also present in sour milk, where it gets its name. Lactic acid, also designated as E270, is used in various industries such as food, cosmetics and pharmaceuticals
Properties of lactic acid
Citric acid is a colorless, crystalline chemical compound that dissolves well in water, making it easy to use in various environments. It exhibits chelating properties, making it effective at binding metals, and acidic properties, allowing it to regulate pH. It is also a natural antioxidant, so it helps protect other substances from oxidation.
Physical properties
It is a slightly viscous, colorless liquid with a characteristic acidic taste. It is highly soluble in water, facilitating its wide use in a variety of products, especially those requiring even distribution. It is also soluble in alcohol, making it a versatile raw material for both food and industrial applications. Its melting point is about 153°C, and its density is about 1,665 g/cm³, which gives it suitable characteristics for various technological processes. In addition, it is hygroscopic, meaning that it readily absorbs moisture from its surroundings.
Chemical properties
Chemically, lactic acid belongs to the hydroxy acid (AHA) group, and its chemical formula is C3H6O3. It has both a hydroxyl group (-OH) and a carboxyl group (-COOH), which gives it unique properties and enables a variety of chemical reactions. Lactic acid is optically active and exists in two isomeric forms – L-(+)-lactic acid and D-(-)-lactic acid. These isomers differ in the way they interact with polarized light and have different applications. L-lactic acid is more popular in cosmetic products due to its milder effects, while both forms are used in the food and pharmaceutical industries.
One of the key chemical aspects of lactic acid is its acidity, with a pKa value of 3.86, making it a medium strength acid. This makes lactic acid effective in lowering the pH of aqueous solutions. The chemical reactivity of lactic acid means that it can form esters in the presence of alcohols and lactates in the presence of bases. This allows it to be widely used in the pharmaceutical and food industries, as well as in the production of biodegradable materials such as polylactide (PLA).
The Versatile Applications of Lactic Acid
Lactic acid (E270) is a widely used compound across various industries, offering benefits in food production, pharmaceuticals, cosmetics, and more. Its broad range of applications makes it an essential ingredient in many products, contributing to both health and functionality.
Lactic Acid in Food
In the food industry, lactic acid plays a significant role as an acidifier and preservative. By lowering pH levels, it helps preserve food and extend shelf life. It’s commonly used in baking, where it interacts with baking soda to create carbon dioxide, aiding in bread formation. Additionally, lactic acid is vital in the dairy industry, improving the stability and volume of butter and speeding up fermentation processes in dairy products. It also helps preserve fruits and enhances the microbiological stability of beer during brewing.
Lactic acid imparts flavor to many foods, contributing to the taste of beer, cheese, pickles, salad dressings, and yogurt, while also providing a mild sourness to sweets. Moreover, it aids in the absorption of essential nutrients like iron, calcium, and amino acids, particularly in dairy products and fermented vegetables.
Lactic Acid in Medicine
Lactic acid is also widely used in the medical field for a range of purposes. In dermatology, it helps remove dead skin cells, promoting skin renewal and treating issues like corns and calluses. When combined with salicylic acid, it is effective in softening and removing hard keratoses.
In gastrointestinal health, lactic acid plays a key role in probiotics, restoring balance to the gut microbiome, particularly after antibiotic treatments or digestive issues. It also helps maintain vaginal health by regulating pH and preventing infections, making it an essential component of intimate hygiene products.
In sports medicine, lactic acid is a byproduct of intense exercise, and its regulation is crucial for optimizing muscle recovery and training performance.
Lactic Acid in Cosmetics
Lactic acid is a popular ingredient in skincare, valued for its moisturizing, exfoliating, and antibacterial properties. At lower concentrations (1-10%), it helps retain moisture and maintain skin elasticity, commonly found in lotions, serums, and creams. At higher concentrations (30-50%), it acts as an exfoliator, promoting skin regeneration and improving texture by removing dead skin cells. Regular use can reduce fine wrinkles and discoloration, contributing to a more youthful appearance.
Lactic acid also plays a significant role in acne care, where it controls bacterial growth and regulates the skin’s pH, supporting a healthy skin barrier. It can be found in various products such as toners, masks, and micellar waters, offering versatile and effective solutions for different skin types.
Products Containing Lactic Acid
- Food: Yogurts, kefirs, buttermilk, aged cheeses, sauerkraut, pickled cucumbers, and beets.
- Cosmetics: Moisturizing and exfoliating creams, chemical facial scrubs, anti-aging products, facial masks, acne treatments, body lotions, and foot care products.
- Pharmaceuticals: Probiotics, intimate hygiene products, dermatological creams for skin conditions like corns or calluses.
Conclusion
Lactic acid plays a crucial role in multiple industries, particularly in food and medicine. Its versatility as a flavor enhancer, preservative, and active ingredient in skincare products highlights its importance across diverse applications. At Zakieh Tejarat, we recognize the significance of lactic acid and are committed to providing high-quality products tailored to the needs of various industries, ensuring smooth transactions and customer satisfaction at every step.
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