Food Grade 99% Malic Acid CAS 6915-15-7

What is Malic acid? How does it work?

Malic acid, also known as hydroxysuccinic acid or 2-hydroxysuccinic acid, has the chemical formula C4H6O5 (HO2CCH(OH)CH2CO2H) and a molecular weight of 134.09. It is a dihydroxycarboxylic acid naturally found in almost all fruits and many vegetables—abundant in fruits such as apples, apricots, blackberries, blueberries, cherries, grapes, peaches, pears, and plums. It is also the main organic acid in grapes and most wines (its concentration in wine can sometimes reach 5 g/L). Chemist Scheele first isolated malic acid from apple juice in 1785, and its English name comes from the Latin word “mālum” (apple).Malic acid is a common food-grade acidity regulator and acidulant. The acidity of malic acid is about 1.1-1.2 times that of citric acid, but its taste is milder and its acidity is more persistent and not sharp. It is known as "the most refreshing food acid". Malic acid is a classic acidulant and flavor enhancer in the food industry, used in everything from sour candies and fruit juices to winemaking and salt and vinegar flavored potato chips. Malic acid has two optical isomers, L- and D-. L-malic acid is a natural product and the synthetic products are racemates.

Basic information : Chemical formula C4H6O5, molecular weight 134.09; IUPAC name 2-hydroxybutanedioic acid; CAS number 6915-15-7 (DL-racemic) / 97-67-6 (L-malic acid) / 636-61-3 (D-malic acid); EC number 230-022-8; UNII 817L1N4CKP; EPA DSSTox DTXSID0027640; ChEBI 6650; Food additive number E296 (EU), INS 296 (Australia and New Zealand); Synonyms: Hydroxybutanedioic acid, 2-hydroxysuccinic acid, malic acid, DL-malic acid.

Structurally and in manufacturing, malic acid contains one chiral carbon, two carboxyl groups, and one hydroxyl group, classifying it as an α-hydroxy dicarboxylic acid. Industrially, racemic malic acid is produced from maleic anhydride via a dehydration reaction (US production capacity was approximately 5,000 tons/year in 2000, according to Ullmann's Encyclopedia of Industrial Chemistry); L-malic acid is produced from fumaric acid via microbial fermentation. Food-grade products require high purity and compliance with food additive standards in various countries, and are in the form of white crystalline powder or granules.

Physically , malic acid is a colorless to white crystalline powder with a pure sour taste: density 1.609 g/cm³; melting point approximately 130℃ (DL type, decomposes); extremely soluble in water (558 g/L @20℃), soluble in ethanol; pKa1 3.40, pKa2 5.20 (two-stage dissociation); flash point approximately 203℃; energy approximately 10 kJ/g; aqueous solution is acidic.

Chemically , malic acid is an α-hydroxy dicarboxylic acid that is chemically active, containing two carboxyl groups that can dissociate in a stepwise manner to yield an acid buffer, hydroxyl and carboxyl groups that can be esterified, form salts (malates) and chelate metal ions (α-hydroxy acid structures are excellent metal chelating agents), react with carbonates such as sodium bicarbonate to release carbon dioxide (leaching effect), dehydrate upon heating to yield maleic acid and fumaric acid, and participate in Maillard reactions and flavor formation.

From the perspective of its mechanism of action, food-grade malic acid plays an irreplaceable role in the food industry due to its five properties: strong acidity, mild and lasting taste, acid buffering, metal chelation, and metabolic activity.

Sourness and mouthfeel mechanism : Malic acid provides strong sourness through two-stage dissociation (pKa1 3.40), with an intensity of about 1.1-1.2 times that of citric acid. However, due to its high sourness threshold and slow release, it has a mild mouthfeel, a long-lasting sourness without being sharp, and a refreshing taste without the "sharpness" of citric acid. It is the best-tasting acidulant.

Acid buffering mechanism : The dissociation equilibrium of carboxyl groups constitutes a pH buffering system, which can stabilize food acidity, assist in preservation and antibacterial action (lowering pH to inhibit microorganisms), and enhance the perception of some flavor components.

Metal chelation mechanism : α-hydroxy acid structures have the ability to chelate metal ions such as calcium, magnesium, iron, and copper. They are used in the chelated form of mineral supplements (calcium malate/magnesium), to inhibit browning of fruits and vegetables (chelating metal ions that catalyze enzyme activity), and to enhance antioxidant and preservative effects.

Acid-base gas production mechanism (leaving) : Malic acid reacts with sodium bicarbonate to release carbon dioxide in a measured amount, providing a leavening effect in baked goods, while also producing a refreshing sour taste.

Metabolic activity mechanism (nutritional function) : L-malic acid is a natural intermediate in the tricarboxylic acid cycle (citric acid cycle), participates in human energy metabolism, can promote energy production and relieve exercise fatigue, and is the biochemical basis for the functionality of sports nutrition and dietary supplements.

In summary , food-grade malic acid (E296) is a versatile food acid used in everything from sour candies and winemaking to baking and sports supplements. Its core features are a mild, long-lasting sour taste and metal chelation, making it suitable for a wide range of applications including beverages, confectionery, brewing, baking, meat products, dairy products, condiments, sports nutrition, dietary supplements, and canning. Its safety has been assessed and approved by JECFA/EFSA/FDA, making it a top-tier acid in the food acidulant family, excelling in both taste and function.

What are all the uses of Malic acid?

1. Beverage acidity regulators and acidulants (core application in the beverage industry)

Application area: Beverage manufacturing.

Corresponding products: Fruit juice drinks such as apple juice and orange juice, carbonated soft drinks, tea drinks, sports drinks, energy drinks, flavored water, plant protein drinks, concentrated fruit-flavored drinks, plum juice, etc.

Why it works for this purpose: Malic acid provides a refreshing, long-lasting, and non-sharp sour taste (the sourness intensity is about 1.1-1.2 times that of citric acid), which can highlight the natural fruit acid flavor of juice. At the same time, its buffering system stabilizes the pH of beverages and helps prevent spoilage and inhibit bacteria. It is the preferred acidulant for adjusting the acidity and enhancing the flavor of beverages (E296 is approved for use in beverages in the EU, the US, Australia and New Zealand).

2. Acidulants for candies and jellies (confectionery industry)

Application areas: Confectionery and gelatin confectionery industry.

Corresponding products: sour hard candy, sour plum candy, fruit juice gummies, gel gummies, jelly, jelly cups, chewing gum, bubble gum, sour candy coating, compressed candy, throat lozenges, etc.

Why it can be used for this purpose: Malic acid has a high sour taste and a slow and long-lasting release, making it an ideal acid source for sour candies. It is often used in combination with citric acid or as a substitute for the weaker-tasting citric acid (Wikipedia clearly states that malic acid is used in sour candies in combination with or as a substitute for citric acid). High concentrations of malic acid coating can produce a strong sour sensation, which is why sour candy packaging includes warnings about oral irritation from excessive consumption.

3. Acidity Adjustment in Fruit Wine and Brewing Industry (Brewing Industry)

Application areas: Wine and fruit wine production.

Corresponding products: wine acidity regulators, cider (cidar) brewing aids, fruit wine acidity regulators, fermented wine pH controllers, tartaric acid substitutes, wine flavor balancers, etc.

Why it can be used for this purpose: Malic acid is the main natural organic acid in grapes and wine (concentration can reach 5 g/L), which determines the acidity and freshness of the wine. During winemaking, the sharp malic acid is transformed into soft lactic acid through malolactic fermentation (MLF). Acidity regulation and flavor balance are both based on malic acid. Malic acid and its salts are also used to supplement acid in years with insufficient acidity.

4. Leavening agents, acidifiers, and acidity adjusters for baked goods (baking industry)

Application areas: Baking and puffed food industry.

Corresponding products: bread leavening agents and acidifiers, cake leavening systems, biscuit leavening agents, shortbread acidity regulators, puffed food acidifiers, fermented pasta improvers, pastry acidity regulators, etc.

Why it can be used for this purpose: Malic acid reacts with sodium bicarbonate to release carbon dioxide, which makes the dough fluffy and produces a refreshing sour taste, improving the flavor of the product; its sour taste is mild and long-lasting, and it is stable at high baking temperatures, making it a common acid component in compound leavening agents and baking acidity regulators.

5. Processing aids for meat and aquatic products (meat processing industry)

Application areas: Meat and aquatic product processing.

Corresponding products: Sausage pH adjuster, ham curing acidity adjuster, dried meat flavor enhancer, braised food acidity adjuster, fish product color protectant, shrimp water retention acidity adjuster, meat product antioxidant enhancer, etc.

Why it works for this purpose: Malic acid lowers the pH of meat products, inhibits the growth of harmful microorganisms, and improves water retention; its α-hydroxy acid chelating structure can chelate metal ions, and works synergistically with antioxidants such as vitamin E to delay the oxidation and rancidity of fats and oils, extend shelf life, and at the same time impart a refreshing sour taste to improve flavor.

6. Acidity adjustment and flavor enhancement in dairy products (dairy industry)

Application area: Dairy industry.

Corresponding products: yogurt acidity regulators, fermented milk flavor enhancers, cheese acidity regulators, dairy beverage acidifiers, ice cream acidity regulators, fruit-flavored yogurt ingredients, cheese curd acidity control agents, etc.

Why it works for this purpose: Malic acid regulates the acidity and pH of fermented dairy products, and works synergistically with lactic acid bacteria fermentation to enhance the refreshing fruity acidity, improve the flavor profile and refreshing taste of yogurt, cheese and ice cream, and its buffering properties prevent excessive acidification from affecting the texture.

7. Acidulants in seasonings and sauces (seasoning industry)

Application areas: Condiments and compound seasonings.

Corresponding products: salad dressing acidifiers, ketchup acidity regulators, barbecue sauce flavoring agents, vinegar flavoring powder (salt and vinegar flavored potato chip seasoning powder), compound seasoning acidifiers, dipping sauce acidity regulators, braising sauce flavoring acid, pickle flavoring acid, etc.

Why it works for this purpose: Malic acid provides a lasting sour taste and enhances the perception of saltiness and spices. It is a key acid source for artificial vinegar flavorings such as "salt and vinegar" potato chips (Wikipedia clearly states that malic acid is one of the sour components of salt and vinegar potato chips). Its solid powder form is convenient for use in seasoning powder formulations.

8. Sports drinks and sports nutrition supplements (sports nutrition field)

Application areas: sports nutrition and functional foods.

Corresponding products: sports drink acidulants, electrolyte effervescent tablets, sports powders, energy supplements, anti-fatigue products, creatine-based sports supplements with acid, sports gels, recovery drinks, etc.

Why it can be used for this purpose: L-malic acid is a natural intermediate in the tricarboxylic acid cycle, which participates in energy metabolism and promotes fatigue recovery (D-malic acid and malate are commonly used in sports supplements); its sour taste can mask the unpleasant taste of electrolyte and amino acid supplements, while also regulating the pH of the preparation solution, making it a multifunctional component of sports nutrition products.

9. Dietary supplements and mineral chelates (health food sector)

Application areas: Dietary supplements and health foods.

Corresponding products: Magnesium malate, Calcium malate, Potassium malate, Complex mineral tablets, Fatigue recovery supplements, Calcium supplements for people with osteoporosis, Oral health lozenges, Energy metabolism support products, Chelated mineral powder, etc.

Why it can achieve this purpose: The α-hydroxy acid structure of malic acid can form stable chelates with minerals such as magnesium, calcium, and potassium, improving the bioavailability of minerals and reducing gastrointestinal irritation. This is the functional basis of well-known chelated mineral supplements such as magnesium malate. At the same time, it participates in energy metabolism and supports exercise recovery and fatigue relief.

10. Acidity Adjustment in Canned Food and Fruit/Vegetable Processing (Food Preservation Field)

Application areas: Canned food and fruit and vegetable processing.

Corresponding products: acidity regulators for canned fruits, acidulants for canned vegetables, acidity regulators for jams, acidity protectants for concentrated fruit juices, color protectants for fruits and vegetables, acidity regulators for candied fruits, bactericidal acidity control agents, acidity regulators for pickled vegetables, etc.

Why it works for this purpose: Malic acid lowers the pH of canned goods and fruit and vegetable products, creating an acidic environment that inhibits heat-resistant bacteria such as Clostridium botulinum, reducing the intensity of sterilization, and assisting in preservation; its chelating effect inhibits the activity of polyphenol oxidase, prevents browning of fruits and vegetables and protects their color, while improving the balance of sweet and sour and flavor.

11. Industrial Cleaning and Metal Surface Treatment Agents (Industrial Cleaning Field)

Application areas: metal cleaning, surface treatment and water treatment.

Corresponding products: environmentally friendly metal cleaning agents, rust removers, boiler and heat exchanger descaling agents, electroplating complexing agents, metal polishing liquids, electronic component cleaning agents, circulating water scale inhibitors, ceramic surface treatment agents, etc.

Why can it be used for this purpose? The α-hydroxy acid structure of malic acid is biodegradable and can chelate metal ions such as calcium, magnesium, and iron. It is an environmentally friendly cleaning agent and descaling agent component that can replace strong acids and phosphorus-based chelating agents. It can gently dissolve rust and scale, complex metal ions to prevent redeposition, and has low corrosiveness and easy wastewater treatment.

12. Feed acidifiers (feed industry)

Application areas: Livestock and poultry feed and breeding.

Corresponding products: feed acidifiers, piglet feed acidifiers, poultry drinking water acidifiers, aquatic feed acidifiers, feed pH adjusters, intestinal health feed additives, anti-mold feed adjuvants, etc.

Why it works: Malic acid lowers the pH of feed and the gastrointestinal tract of animals, inhibits harmful bacteria such as Escherichia coli, promotes the growth of beneficial bacteria and the activity of digestive enzymes, improves the digestion and absorption and intestinal health of young animals such as piglets, and provides energy metabolism substrates (intermediates of the tricarboxylic acid cycle). It is a commonly used organic feed acidifier.

13. Reagent-grade chiral resolving agents and organic synthesis building blocks (in the fields of detection and scientific research laboratories)

Application areas: Organic synthesis and analytical chemistry laboratories.

Corresponding products: chiral resolving agents, buffer solution components, chiral synthetic building blocks, raw materials for the synthesis of L-malic acid derivatives, chemical analysis reagents, scientific research and teaching reagents, enzyme research substrates, etc.

Why it can be used for this purpose: L-malic acid is a natural chiral source. Its carboxyl and hydroxyl groups can form salts with racemic amines to achieve chiral resolution. The two carboxyl groups and one hydroxyl group structure of malic acid is a common building block for synthesizing chiral derivatives and chelates. At the same time, its dissociation equilibrium makes it a commonly used reagent in laboratory buffers and biochemical research.

Summarize

Malic acid (C4H6O5, E296, CAS 6915-15-7) is a multifunctional food acid used in everything from sour candies and sodas to winemaking, from baking to sports supplements. With its five properties of strong acidity, smooth and lasting flavor, acid buffering, metal chelation, and metabolic activity, it has thirteen mature applications across various sectors, including beverage acidity regulation, candy and jelly acidifiers, fruit wine acidity regulation, baking leavening, meat processing aids, dairy flavor enhancement, condiment and sauce acidifiers, sports nutrition supplements, dietary supplement mineral chelation, canned fruit and vegetable processing, industrial cleaning and metal surface treatment, feed acidifiers, and reagent-grade chiral resolving agents. Beverage acidity regulation and sour candies are the two core mass-market sectors, while sports nutrition and chelated minerals represent high-value-added functional directions.