Food Grade 99.4% Glycine CAS 56-40-6

What is Glycine? How does it work?

Glycine, also known as aminoacetic acid, has the chemical formula C2H5NO2, a molecular weight of 75.07, and CAS number 56-40-6. It is the simplest amino acid (containing only two carbons) and one of the non-essential amino acids for the human body (becoming conditionally essential under certain conditions). It is a white, sweet-tasting crystal (from the Greek word "glykys," meaning "sweet"). Industrially, it is synthesized through chemical methods such as ammonolysis of chloroacetic acid or by the hydrolysis of gelatin. In the food industry, it is used as a flavor enhancer, nutritional supplement, and preservative. In the food industry, glycine is known as the "invisible silencer of bitterness after sweeteners" and the "roundness regulator of seasonings": it is slightly sweet, can counteract the bitterness of sweeteners such as saccharin, and can delay the rancidity of animal and vegetable oils. It is widely used in beverages, candies, chewing gum, seasonings, meat products, and nutritional foods. Note: Glycine is non-toxic, inexpensive, and readily available. Industrial-grade glycine is also available (as an intermediate for glyphosate, in electroplating, and as a buffer solution).

Basic information : Chemical formula C2H5NO2 (H2N-CH2-COOH), molecular weight 75.07; CAS number 56-40-6; EC/EINECS number 200-272-2; UNII TE7660XO1C; FEMA number 3287 (food flavoring); three-letter abbreviation Gly/G, single letter G; aliases: glycine, aminoacetic acid, aminoacetic acid, glycocoll, aminoethanoic acid.

Structurally and in manufacturing, glycine is the smallest amino acid containing both an amino group (-NH2) and a carboxyl group (-COOH). Its side chain has only one hydrogen atom, allowing it to enter hydrophobic environments and exhibiting unique conformational flexibility. Industrially, it is mainly synthesized chemically through the reaction of chloroacetic acid and ammonia (chloroacetic acid ammonolysis). It can also be produced by the hydrolysis of proteins such as gelatin (gelatin itself contains approximately 19% glycine, making it a rich natural source). Food-grade products must meet food-grade purity and heavy metal limits; it is a white crystalline powder.

Physically , food-grade glycine is a white crystalline or crystalline powder with a distinctive sweetness (approximately 70%-80% of that of sucrose); melting point is approximately 233℃ (decomposes); it is extremely soluble in water (approximately 25 g/100 mL at 25℃) and almost insoluble in organic solvents such as ethanol and ether; density is approximately 1.16 g/cm³; isoelectric point (pI) is approximately 5.97; it is non-hygroscopic, stable, and has good thermal stability.

Chemically , glycine is an amphoteric amino acid: it contains a basic amino group and an acidic carboxyl group, with a pKa1 of approximately 2.35 and a pKa2 of approximately 9.78. It has buffering capacity (pH regulation) near its isoelectric point; it can complex with metal ions to form glycinate salts (such as copper glycinate and zinc glycinate); it can chelate with metal ions related to lipid oxidation to delay rancidity; its amino group can undergo Maillard reactions with reducing sugars to participate in food flavor; it is non-toxic and metabolizes into CO2 and water.

From the perspective of its mechanism of action, food-grade glycine plays an irreplaceable role in the food industry due to its five properties: enhancing sweetness, masking bitterness, chelating and preserving, buffering and pH adjustment, and providing nutritional supplementation.

Mechanism of enhancing sweetness : Glycine itself is slightly sweet, which can soften and round out the umami flavor of monosodium glutamate (MSG) and other flavors, making the flavor of compound seasonings more mellow and harmonious; its sweetness can also work synergistically with other sweeteners to improve the layers of sweet taste.

Mechanism of masking bitterness : Glycine can significantly counteract the aftertaste of sweeteners such as saccharin (Hawley's Chemical Dictionary clearly states that it "reduces the bitterness of saccharin"). Its mechanism is related to the interaction between its molecular structure and bitter/sweet receptors, making the sweetness of sugar-free beverages and low-sugar candies purer.

Chelating and preservative mechanism : Glycine can complex with metal ions such as copper and iron (Wikipedia states that its preservative properties may originate from complexation with metal ions), inhibiting the oxidation of oils catalyzed by metal ions, thereby delaying the rancidity of animal and vegetable oils (Hawley's states that it "delays the rancidity of animal and vegetable oils"), and playing a synergistic role in anti-oxidation and preservation.

pH buffering mechanism : Glycine is an amphoteric amino acid with good buffering capacity around its isoelectric point of 5.97, which can stabilize the pH value of food systems and be used as a food pH regulator.

Mechanism of nutritional supplementation : Glycine is a non-essential amino acid that participates in the synthesis of creatine, glutathione, heme and collagen. As a source of nutritional fortifiers and dietary supplements, it can be used as an amino acid supplement in special purpose foods and sports nutrition products.

In summary , food-grade glycine (E640) is a multifunctional food amino acid that can be used to enhance the flavor of sugar-free soft drinks, make seasonings smoother, improve the shelf life of oily foods, and fortify nutritional foods. With flavor enhancement and bitterness masking as its core functions, it is used in beverages, confectionery, seasonings, meat products, oily foods, and nutritional foods. Its FDA 21 CFR 172.320 approval and JECFA "no safety concerns" rating make it one of the most commonly used amino acid additives in the food industry.

What are all the uses of Glycine?

1. Beverage flavor enhancers and sweeteners (beverage industry)

Application areas: sugar-free and low-sugar beverage processing.

Corresponding products: sweeteners for sugar-free soft drinks, flavor enhancers for low-sugar sports drinks, flavor enhancers for tea drinks, flavor enhancers for fruit-flavored drinks, sweeteners for fruit juice drinks, flavor enhancers for electrolyte drinks, sweeteners for sugar-free sparkling water, flavor enhancers for low-calorie drinks, etc.

Why it can be used in this way: Glycine has a slightly sweet taste and can significantly counteract the bitter aftertaste of sweeteners such as saccharin (Hawley's records that it "reduces the bitterness of saccharin"), making the sweetness of sugar-free and low-sugar beverages pure and rounded; its flavor-enhancing effect also softens the overall flavor, and it is a commonly used bitterness masking and taste-improving component in beverage sweetener systems.

2. Sweeteners for candies and chewing gum (confectionery industry)

Application areas: Hard candy, soft candy and chewing gum manufacturing.

Corresponding products: sweetness improvers for hard candies, flavor improvers for soft candies, flavor enhancers for fruit-flavored candies, sweetness modifiers for chewing gum, sweeteners and bitterness maskers for sugar-free candies, taste improvers for mints, flavor enhancers for compressed candies, flavor harmonizers for lollipops, etc.

Why it can be used in this way: Glycine itself has about 70%-80% of the sweetness of sucrose. When combined with sweeteners such as saccharin, it can mask the bitterness and enhance the sweetness (Wikipedia states that glycine "counters the aftertaste of saccharin"), making the sweetness of candy and chewing gum purer and longer-lasting. It is an important component of sweetener compounding systems.

3. Flavor enhancers for seasonings and soup bases (seasoning industry)

Application areas: compound seasoning and soup base manufacturing.

Corresponding products: soy sauce flavor enhancer, oyster sauce flavor enhancer, chicken essence flavor improver, compound seasoning flavor enhancer, soup powder flavor enhancer, instant noodle seasoning flavor enhancer, hot pot base flavor improver, marinade flavor enhancer, sauce roundness regulator, etc.

Why it can be used in this way: Glycine can soften and round out the umami flavor of umami enhancers such as monosodium glutamate (FDA 21 CFR 172.320 approves it as a flavor enhancer), making the flavor of compound seasonings such as soy sauce, oyster sauce, and chicken essence more mellow, harmonious, and less sharp. It is an important amino acid component for enhancing the flavor of seasonings.

4. Flavor enhancers for meat and aquatic products (meat processing industry)

Application areas: Meat and aquatic product processing.

Corresponding products: sausage flavor enhancer, ham flavor improver, cured meat preparation, dried meat flavor enhancer, braised meat product flavor enhancer, pickled fish flavor enhancer, surimi product flavor improver, shrimp paste seasoning aid, canned meat product flavor enhancer, etc.

Why it can be used for this purpose: Glycine is used as a flavor enhancer in meat and aquatic products to improve product flavor, mask unpleasant odors and enhance sweetness (Chinese GB 2760 allows glycine to be used as a flavor enhancer in meat and aquatic products). Its mild sweetness works synergistically with the flavor of protein to make the meat products more flavorful.

5. Antioxidant and preservative additives for oil and fat products (oil and nut food industry)

Application areas: Processing of oily foods and oil products.

Corresponding products: antioxidants for mayonnaise, preservatives for salad dressing, antioxidants for oily nuts, antioxidants for fried foods, preservatives for sauces, antioxidants for margarine, preservatives for canned meat sauce, and inhibitors of rancidity of fats and oils.

Why it can be used in this way: Glycine can complex with metal ions such as copper and iron, inhibiting the oxidation of oils catalyzed by metal ions, thereby delaying the rancidity of animal and vegetable oils (Wikipedia records that its preservative properties may originate from complexation with metal ions, and Hawley's records that it "delays the rancidity of animal and vegetable oils"). It plays a synergistic role in anti-oxidation and preservation in oily foods, and extends shelf life.

6. Nutritional fortification and dietary supplements (nutrition and health food sector)

Application areas: Nutritionally fortified foods and dietary supplements.

Corresponding products: protein powder amino acid components, amino acid supplements, sports nutrition food fortifiers, special purpose food amino acids, vitamin complex tablets amino acid excipients, fortified beverages, glutathione precursor supplements, creatine synergist supplements, collagen peptide auxiliary ingredients, etc.

Why it can be used for this purpose: Glycine is an amino acid nutrient supplement approved by the FDA 21 CFR 172.320. As a protein component, it participates in the synthesis of creatine, glutathione, heme and collagen, and is an important source of amino acids for nutritional fortification and dietary supplementation.

7. Pet food and animal feed additives (pet food and feed industry)

Application areas: Pet food and animal feed manufacturing.

Corresponding products: pet dry food palatability improvers, pet wet food flavor enhancers, pet snack flavoring agents, chicken feed additives (as recorded in Merck Index), methionine synergistic feed supplements, glycine copper feed supplements, glycine zinc feed supplements, ruminant feed amino acids, aquatic feed palatability enhancers, etc.

Why it can be used for this purpose: Glycine is used as a feed additive to improve the palatability and amino acid nutritional balance of animal diets (Merck Index and HSDB record it as a chicken feed additive and nutrient). Metal glycine salts (copper glycine, zinc glycine, etc.) are bioavailable supplements of trace elements in animal feed (as recorded in Wikipedia) and are widely used in livestock, poultry and aquatic feeds.

8. Food buffers and pickling processing aids (gel and pickled food industry)

Application areas: Processing of gelled and pickled foods.

Corresponding products: pH buffer for jelly, pH regulator for pudding, pickling aid for kimchi, pH stabilizer for preserved vegetables, preservative for pickled products, buffer for beverages, acidity regulator for jam, buffer for canned food, etc.

Why it can be used for this purpose: Glycine is an amphoteric amino acid (pKa1 approximately 2.35, pKa2 approximately 9.78, isoelectric point approximately 5.97). It has good buffering capacity near its isoelectric point, which can stabilize the pH value of jellies, puddings, beverages and pickled foods (FDA/EPA data also lists it as a pH regulating agent for food), and provides a mild antiseptic and preservation aid for pickling systems.

9. Glyphosate herbicide synthesis intermediates (agrochemical industry)

Application areas: Pesticide synthesis and agrochemical industry.

Corresponding products: intermediates for the synthesis of glyphosate technical grade, intermediates for glyphosate isopropylamine salt formulations, raw materials for herbicide production, intermediates for Roundup herbicides, intermediates for glyphosate-resistant genetically modified herbicides, etc.

Why it can be used for this purpose: Glycine is a key synthetic intermediate in the production of glyphosate (Wikipedia clearly states that glycine is an intermediate in the manufacture of products such as glyphosate). Glyphosate is the most widely used herbicide in the world, and glycine has therefore become an important bulk chemical raw material in the agrochemical industry.

1.0 . Cyanide-free electroplating complexing agent (electroplating industry)

Application areas: Electroplating and metal surface treatment.

Corresponding products: cyanide-free alkaline copper plating complexing agent, cyanide-free nickel plating complexing agent, electroplating solution pH buffer, metal complexing brightener, plating complexing aid, chemical plating complexing agent, etc.

Why it can be used in this application: The amino and carboxyl groups of glycine can form stable complexes with metal ions such as copper and nickel (PubChem records its industrial use as a plating agent and chelating agent), replacing cyanide as a complexing agent for cyanide-free electroplating, achieving environmentally friendly electroplating and improving the quality of the coating.

1.1 . Buffer solutions and analytical reagents (laboratory and analytical chemistry fields)

Application areas: Biochemistry, molecular biology and analytical chemistry laboratories.

Corresponding products: SDS-PAGE electrophoresis buffer (Tris-glycine buffer) components, protein electrophoresis buffers, biochemical buffers, analytical reagents, titration aids, cell culture medium buffer components, analytical buffers, chromatography buffers, etc.

Why it can be used for this purpose: Glycine has good amphoteric buffering capacity around its isoelectric point of 5.97 (Merck Index records its use as an organic chemical buffer and reagent), Tris-glycine is the standard buffer system for SDS-PAGE protein electrophoresis, and glycine buffer is widely used in biochemical and analytical experiments.

1.2 . Cosmetic skincare and haircare additives (cosmetics industry)

Application areas: Skin care and hair care products.

Corresponding products: moisturizing buffer in skin care water, skin conditioning agent in face cream, moisturizing agent in serum, antistatic agent in shampoo, conditioning agent in hair conditioner, buffer in facial cleanser, moisturizing ingredient in face mask, buffer in sunscreen, etc.

Why it can be used for this purpose: Glycine is an amino acid component of the human body's natural moisturizing factor (NMF), which has moisturizing and skin conditioning effects. It also acts as a buffer to stabilize the pH of the formula and as an antistatic agent to improve the combability of hair (the EU Cosmetic Ingredients Catalogue records its use in antistatic, hair conditioning, buffering and skin conditioning). It is widely used in skin care and hair care products.

Summarize

Glycine (C2H5NO2, E640/INS 640, CAS 56-40-6) is a multifunctional amino acid with six major properties: "flavor enhancement and sweetness modification, bitterness masking, chelation and preservation, pH buffering and adjustment, nutritional supplementation, and complexation coordination." It has mature applications in beverage flavor enhancement and sweetness improvement, candy and chewing gum sweetness improvement, seasoning and soup flavor enhancement, meat and seafood flavor enhancement, oil and fat antioxidant and preservation, nutritional fortification and dietary supplementation, pet food and feed additives, food buffering and pickling aids, acid resistant agents, glyphosate herbicide intermediates, cyanide-free electroplating complexing agents, buffer solution analytical reagents, chelated fertilizers and foliar fertilizers, and cosmetics, skincare, and haircare products. Among these, beverage sweetness improvement, seasoning flavor enhancement, and glyphosate intermediates are its three core areas, while cyanide-free electroplating is a high-value direction.