Introduction to Sodium Lactate and Its Applications

Sodium lactate, with the molecular formula C₃H₅NaO₃, is a colorless or nearly colorless, transparent liquid that is fully miscible with water, ethanol, and glycerin. It is used in food preservation, moisture retention, flavor enhancement, and as a pharmaceutical raw material.

　　Sodium lactate, with the molecular formula C₃H₅NaO₃, is a colorless or nearly colorless, transparent liquid that readily mixes with water, ethanol, and glycerin. It is used in food preservation, moisture retention, flavor enhancement, and as a pharmaceutical raw material.

　　Sodium Lactate – Properties

　　Sodium lactate, with the simplified structural formula CH3CH(OH)·COONa, is a colorless to slightly yellowish, transparent, viscous liquid. It is hygroscopic and miscible in any proportion with water, ethanol, or glycerin. Its aqueous solution is neutral in pH.

　　Sodium Lactate – Preparation Method

　　Add an equal volume of sodium hydroxide (or sodium carbonate) solution to lactic acid solution, bring the mixture to a boil to drive off carbon dioxide completely, adjust the pH to 7, then decolorize with activated carbon, filter the solution, and finally concentrate the filtrate at 25°C to obtain sodium lactate.

　　Sodium Lactate – Main Applications

　　To eat

　　(1) Widely used in the meat and poultry food processing industry as an emulsifier, humectant, flavor enhancer, quality improver, antioxidant synergist, and pH regulator, it helps intensify flavors, inhibit the growth of pathogenic bacteria in food, and extend product shelf life.

　　(2) Sodium lactate, used as a food preservative, flavor enhancer, antifreeze agent, and humectant, has already replaced sodium benzoate as a preservative in the food industry in several countries. Compared to sodium benzoate, sodium citrate, and sodium sorbate, sodium lactate offers unparalleled advantages. Notably, when applied to meat products, it delivers remarkable benefits: 1. **Extended shelf life**: It can extend product freshness by 30% to 100%, or even longer in some cases; 2. **Inhibition of harmful pathogens**: Sodium lactate effectively suppresses the growth of foodborne bacteria such as E. coli O157:H7, Listeria monocytogenes, and Clostridium botulinum, significantly enhancing food safety; 3. **Enhanced flavor retention**: It helps preserve and even amplify the natural flavors of meat products; 4. **Reduced sodium content with added health benefits**: As a salt alternative, sodium lactate not only allows for lower sodium levels but is also safer for individuals with conditions like low-salt diets—such as those managing heart disease, hypertension, or kidney issues. For instance, it can be used to formulate fitness-friendly salts that maintain a balanced potassium-to-sodium ratio.

　　Medical

　　(1) Sodium lactate is primarily used as an injectable solution in the medical field, serving mainly to replenish body fluids and help maintain electrolyte balance within the body. Sodium lactate injection can effectively address dehydration caused by diarrhea, as well as poisoning resulting from conditions like diabetes and gastritis. It is also employed to restore fluid or electrolyte levels in parenteral/parenteral solutions and is widely utilized in continuous ambulatory peritoneal dialysis (CAPD) solutions for patients with kidney disease, as well as in conventional hemodialysis as a dialysis fluid.

　　(2) Sodium lactate is used as an electrolyte and osmotic agent in intravenous solutions, as well as in enteral disinfectants, mouthwashes, and bladder instillations, among other applications.

　　(3) Sodium lactate is also widely used in the preparation of Ringer's solution, formulated into an injectable solution for treating metabolic acidosis.

　　(4) Sodium lactate is highly effective in treating skin disorders, such as severe dryness caused by conditions like xerosis. Lactic acid and its salts possess antimicrobial properties, making them a popular ingredient in anti-acne products. They are often used in combination with other active ingredients to create synergistic effects.

　　Cosmetics

　　(1) Sodium L-lactate is also widely used as a moisturizing agent in skincare products, helping to keep skin hydrated and reduce the appearance of wrinkles.

　　(2) Sodium lactate is a natural humectant—about one-quarter of the human skin’s stratum corneum consists of sodium lactate. When used in cosmetics, sodium lactate forms a hydrating film with other ingredients, effectively preventing moisture loss from the skin and helping maintain a soft, smooth, and comfortably hydrated complexion. This action also helps reduce the appearance of wrinkles, making it a widely popular moisturizing agent in skincare products. Additionally, lactic acid serves as an effective pH regulator. L-lactate salts, meanwhile, have emerged as a next-generation skin-lightening ingredient that can deliver synergistic effects when combined with other whitening agents.

　　(3) Sodium lactate can be used as a moisturizing agent in various bathing products, such as shower gels, bar soaps, and body lotions. In liquid soaps, bath bars, and shampoos, it serves as a pH adjuster. Additionally, when added to bar soaps, sodium lactate helps minimize moisture loss during storage, thereby preventing the soap from cracking or drying out prematurely.