Tartaric Acid in Food & Beverage Products

What is Tartaric Acid?
Use of Tartaric Acid in the Food and Beverage Industry
Industry Applications in the Food Industry
Product Examples
Properties of Tartaric Acid
Typical Formulations
Tartaric Acid Formulation Considerations
Safety & Regulatory Considerations
Fun Facts About Tartaric Acid
Additional Resources

Tartaric acid is a naturally occurring organic acid found in various fruits, plants, and wine. It’s used commercially in the food industry as a flavoring agent and an additive. Tartaric acid exhibits a slightly astringent and refreshing sour taste that contributes a strong tart flavor to food and beverages.

What is Tartaric Acid?

The chemical name of tartaric acid is 2,3-dihydroxybutanedioic acid, and its chemical formula is C₄H₆O₆. It is a diprotic acid acting as a weak acid in solution. Tartaric acid is present in the form of 3 stereoisomers: dextro, levo, and meso. Dextro and levo are optically active, and meso is optically inactive.

Although tartaric acid was first isolated by the alchemist, Jabir Ibn Hayyan, Swedish chemist Carl Wilhelm Scheelea was credited for its discovery in 1769. Experiments with tartaric acid date back to the Romans and the Greeks, who observed “tartar” as a partially purified form of acid.

Chemical structure of tartaric acid. Source: Wikipedia

How is Tartaric Acid Produced?

Tartaric acid naturally occurs in plants like grapes, apricots, apples, bananas, avocados, and tamarinds. It can be isolated from these sources. Also, it is one of the primary acids found in wine. It is produced commercially by chemically treating potassium tartrate, a by-product of the wine industry.

Use of Tartaric Acid in the Food and Beverage Industry

Tartaric acid is added to foods to give them a tart and tangy flavor. It also acts as an acidulant in multiple food applications, lowering the pH of food products. This functionality also contributes to its preservative capabilities. In baking, tartaric acid is used to impart leavening to baked goods. It is also used in candy and frozen desserts, as well as in non-alcoholic and alcoholic beverages and confectionery items.

Tartaric acid is an essential additive in wine due to its prominent role in maintaining its chemical stability and color. It is used to prepare more balanced wines from a taste perspective, resulting in an increase in acidity and a decrease in pH content. It lowers the pH of fermenting wort to prevent bacteria in brewing as well and acts as a preservative after fermentation.

Industry Applications in the Food Industry

Tartaric acid is a multipurpose food additive that serves a variety of functions, including:

Acidulant
Flavoring agent
Preservative (antimicrobial agent)
Flavor enhancer
Raising agent
Sequestrant
Antioxidant
pH control agent

Function	Applications
Acidulant, Preservative, Flavor Enhancer	Powder mixes, Jams, Jellies, Sauces
Acidulant, pH Regulator, Flavor Enhancer	Candies, Gummies, Soft Chews, Frozen Desserts
Leavening agent, Acidulant, Flavor Enhancer, Antioxidant	Cake, Bread
Acidulant, Flavor Enhancer, Effervescent	Carbonated Beverages, Acidified Beverages, Fruit Juices, Marmalades, Carbonated Water
pH Regulator, Stabilizer	Wine, Brewing

Product Examples

Type	Examples
Convenience Foods	Powder Mixes, Jams, Jellies, Sauces
Confectionery	Candies, Gummies, Soft Chews, Frozen Desserts
Bakery	Cake, Bread
Alcoholic Beverages	Wine, Brewing
Non-Alcoholic Beverages	Carbonated Beverages, Acidified Beverages, Fruit Juices, Marmalades, Carbonated Water

Properties of Tartaric Acid

Molecular Weight	150.09 g/mol
Melting Point	171°C
Density	1.79 g/cc
Appearance	Crystalline white solid
Solubility	Freely soluble in water and ethanol
Heat of Solution	-14.42 KJ/mol

Typical Formulations

Candy

A dry, free-flowing candy mix powder was prepared from the following components. Tartaric acid is used as a flavoring agent in this formulation. The resulting product is a relatively dry and crumbly mix. The mix is then heated at 250° F for 30 minutes or until all ingredients are melted. The resulting candy melt is then cooled in a refrigerator.

Ingredient	% Composition (Sugar Basis)
Fructose	100
Tartaric Acid (alone or in combination with other acids)	3.0
Color	0.02
Flavor (fruit flavors)	0.2
Propylene glycol	1

Source: Google Patents

Effervescent Powder

An effervescent powder that can be used for obtaining an instant sparkling beverage was made according to the following formulation. The resulting product can be used in powder, granule, or tablet form — it self-cools and releases gas when dissolved in liquids suitable for ingestion, for example, water, natural fruit juices, etc. The formulation may contain other additives, like sweeteners, sugars, anti-humectants, colorants, flavorings, etc.

Ingredient	Parts
Sodium Bicarbonate	2
Citric Acid	1
Tartaric Acid	3

Source: Google Patents

Jelly

Papaya jelly was made using papaya fruit pulp and the following components.

Ingredient	% Pulp Basis
Papaya Pulp (adding sugar/ liquid glucose)adjusted to 80-81 TS	100 %
Citric Acid: Malic Acid: Tartaric Acid (40:35:25)	1.2 %
Sodium citrate: Sodium Tartrate (1:1)	0.3 %

Source: Research Gate

Tartaric Acid Formulation Considerations

Tartaric acid’s properties have several important implications for the formulation, as described in the table below.

Physical Forms

The pKa values for tartaric acid are: pKa₁=2.98 and pKa₂=4.34. The 1 mM solution of tartaric acid has a pH of 3.18. Adding tartaric acid to food products lowers the system’s pH, imparting many other benefits, including increased shelf life. By lowering the pH of a solution, the tartaric acid acts as an effective antimicrobial agent by creating an environment too acidic for most microorganisms to grow.

Dosage

The dosage of tartaric acid in formulations ranges from 0.05% to 0.5% (or more), depending on the product and the desired effect. However, it is generally used with other acids, such as citric acid and malic acid, to obtain the desired flavor profile as an additive in food products.

Effects on pH Properties

The pKa values for tartaric acid are: pKa₁=2.98 and pKa₂=4.34. The pH of 1 mM solution of tartaric acid has a pH of 3.18. The addition of tartaric acid to food products lowers the pH of the system imparting many other benefits including increased shelf life. By lowering the pH of a solution, the tartaric acid acts as an effective antimicrobial agent by creating an environment too acidic for most microorganisms to grow.

Effects on Shelf Life

Tartaric acid provides multiple benefits in terms of shelf life, including increased shelf stability, color stability, and preservation. Tartaric acid acts as a chelating agent and produces canned fruit products. Chelates are formed when an organic acid binds with a metal, preventing its reaction with another chemical. Chelating agents prevent enzymatic browning by forming a complex free metal and inhibitors through an unshared pair of electrons in their molecular structures.

Effects on Sensory Properties

Tartaric acid functions as a sequestrant. It aids in its activity as an antioxidant. It has also been reported to have anti-hypertensive potential. Tartaric acid and dietary fibers have been reported to synergistically improve digestive health. It was reported to show antihyperglycemic and antidyslipidemic effects and improve glucose tolerance.

Biological Activity

Tartaric acid exhibits a slightly astringent and refreshing sour taste. It has a more robust, sharper taste than citric acid. Tartaric acid hits the tip and front quarter of the tongue. It is expected to give the classic overt, mouthwatering, and jaw-clenching experience often described as acidity in wine.

Sources

The pKa values for tartaric acid are pKa₁=2.98 and pKa₂=4.34. The 1 mM solution of tartaric acid has a pH of 3.18. Adding tartaric acid to food products lowers the system’s pH, imparting many other benefits, including increased shelf life. By lowering the pH of a solution, the tartaric acid acts as an effective antimicrobial agent by creating an environment too acidic for most microorganisms to grow.

Comparison with Other Acidulants

Tartaric acid has the edge over other acidulants for food applications because it is a natural acid with an astringent flavor. As a diprotic acid, it can donate two protons per molecule, making it more effective as an acidulant than monoprotic acids. Tartaric acid is the most water-soluble of the solid acidulants.

Generally, tartaric acid is used in smaller doses than other acidulants, as it is more potent. For example, citric acid is usually used in a 1-2% concentration, while tartaric acid is used in a 0.1-0.2% concentration.

Safety & Regulatory Considerations

FDA Information	L (+) -tartaric acid (E334) is a food additive in the EU. The Scientific Committee for Food established an acceptable daily intake of 30 mg/Kg body weight/day.
EU Information	In the EU, L (+) -tartaric acid (E334) is a food additive. The Scientific Committee for Food established an acceptable daily intake of 30 mg/Kg body weight/day.

Safety & Toxicity of Tartaric Acid

Overconsumption could lead to increased thirst, vomiting, diarrhea, abdominal pain, and gastrointestinal inflammation.

Identification Numbers

CAS Number	L (+) tartaric acid: 87-69-4D (-) tartaric acid: 147-71-7Mesotartaric acid: 147-73-9
EC Number	201-766-0
E No. (Food Additive)	E 334
INS No. (Food Additive)	INS 334
JECFA Number	621

Fun Facts About Tartaric Acid

Tartaric acid has been used for centuries in winemaking. The ancient Greeks and Romans were aware of its presence in wine sediments, known as tartar, and used it for medicinal purposes.
Tartaric acid may appear as “wine diamonds” found in the cork of a wine bottle.
Tartaric acid is used to make solutions for determining glucose in the medical industry.
Tartaric acid has been used in traditional medicine for its laxative properties. It is sometimes included in pharmaceutical formulations and oral care products.