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Jai Ganesh

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Malic Acid

Malic Acid

Gist

Malic acid (C4H6O5) : Malic acid is found in apples, which is where its name comes from. It is also naturally present in other fruits like cherries, grapes, apricots, and watermelons, as well as in some vegetables such as carrots and broccoli.

* Apples: The name "malic" is derived from the Latin word malum, meaning apple, as it is the fruit where this acid is most abundant.
* Other fruits: It's also found in cherries, grapes, apricots, and watermelons.
* Vegetables: Some vegetables, including carrots and broccoli, also contain malic acid.
* Role in fruit: Malic acid is responsible for the sour taste in many fruits.

It is a dicarboxylic organic acid naturally found in fruits, known for its sour taste and tartness.

It is used as a food additive to enhance flavors, an ingredient in some medical and dental products, and in technical applications like metal cleaning. Malic acid is also produced by all living organisms during cellular metabolism.

Summary

Malic acid is an alpha hydroxy acid found in certain fruits and wines. It's used in foods and cosmetics, and sometimes as medicine.

Malic acid is sour and acidic. This helps to clear away dead skin cells when applied to the skin. Its sourness also helps to make more saliva in people with dry mouth. Malic acid is also involved in the Krebs cycle. This is a process the body uses to make energy.

People commonly use malic acid for dry mouth. It is also used for acne, fibromyalgia, fatigue, wrinkled skin, and many other conditions, but there is no good scientific evidence to support these uses.

Malic acid is an alpha hydroxy acid. Don't confuse it with other alpha hydroxy acids (AHAs).

Uses & Effectiveness:

Possibly Effective for

Dry mouth. Using a mouth spray or sucking on a lozenge containing malic acid seems to improve symptoms of dry mouth.
There is interest in using malic acid for a number of other purposes, but there isn't enough reliable information to say whether it might be helpful.

Side Effects

When taken by mouth: Malic acid is commonly consumed in foods. Malic acid is possibly safe when used as a medicine for up to 6 months.

When applied to the inside of the mouth: Malic acid is possibly safe when used in a mouth spray or lozenge for up to 6 months.

When applied to the skin: There isn't enough reliable information to know if malic acid is safe. It might cause side effects such as skin and eye irritation.

Details

Malic acid is an organic compound with the molecular formula HO2CCH(OH)CH2CO2H. It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms (L- and D-enantiomers), though only the L-isomer exists naturally. The salts and esters of malic acid are known as malates. The malate anion is a metabolic intermediate in the citric acid cycle.

Biochemistry

L-Malic acid is the naturally occurring form, whereas a mixture of L- and D-malic acid is produced synthetically. 

Malate plays an important role in biochemistry. In the C4 carbon fixation process, malate is a source of CO2 in the Calvin cycle. In the citric acid cycle, (S)-malate is an intermediate, formed by the addition of an -OH group on the si face of fumarate. It can also be formed from pyruvate via anaplerotic reactions.

Malate is also synthesized by the carboxylation of phosphoenolpyruvate in the guard cells of plant leaves. Malate, as a double anion, often accompanies potassium cations during the uptake of solutes into the guard cells in order to maintain electrical balance in the cell. The accumulation of these solutes within the guard cell decreases the solute potential, allowing water to enter the cell and promote aperture of the stomata.

In food

Malic acid was first isolated from apple juice by Carl Wilhelm Scheele in 1785. Antoine Lavoisier in 1787 proposed the name acide malique, which is derived from the Latin word for apple, mālum—as is its genus name Malus. In German it is named Äpfelsäure (or Apfelsäure) after plural or singular of a sour thing from the apple fruit, but the salt(s) are called Malat(e). Malic acid is the main acid in many fruits, including apricots, blackberries, blueberries, cherries, grapes, mirabelles, peaches, pears, plums, and quince, and is present in lower concentrations in other fruits, such as citrus. It contributes to the sourness of unripe apples. Sour apples contain high proportions of the acid. It is present in grapes and in most wines with concentrations sometimes as high as 5 g/L. It confers a tart taste to wine; the amount decreases with increasing fruit ripeness. The taste of malic acid is very clear and pure in rhubarb, a plant for which it is the primary flavor. It is also the compound responsible for the tart flavor of sumac spice. It is also a component of some artificial vinegar flavors, such as "salt and vinegar" flavored potato chips.

The process of malolactic fermentation converts malic acid to much milder lactic acid. Malic acid occurs naturally in all fruits and many vegetables, and is generated in fruit metabolism.

Malic acid, when added to food products, is denoted by E number E296. It is sometimes used with or in place of the less sour citric acid in sour sweets. These sweets are sometimes labeled with a warning stating that excessive consumption can cause irritation of the mouth. It is approved for use as a food additive in the EU,[13] US and Australia and New Zealand (where it is listed by its INS number 296).

Malic acid contains 10 kJ (2.39 kilocalories) of energy per gram.

Additional Information

Malic acid benefits can include acne treatment, and skin care such as exfoliation and hydration. It is an alpha hydroxy acid, found naturally in fruits and wines and used as an ingredient in medications and skin care products. Some people use it to treat symptoms of a dry mouth due to medications, and there's some research evidence that it can help.

Malate, the ionized form of malic acid, plays a small role in the Krebs cycle, the primary way our bodies generate energy. It has been used to treat chronic fatigue and fibromyalgia. More research is needed to identify and understand the health benefits of malic acid.

In the United States, the Food and Drug Administration (FDA) does not regulate dietary supplements the way it regulates prescription medications. As a result, some supplement products may not contain the ingredients listed on the label. When choosing a supplement, look for products independently tested or certified by organizations such as the National Sanitation Foundation (NSF), United States Pharmacopeia (USP), or ConsumerLab. For personalized guidance, consult your healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.

Uses of Malic Acid

Malic acid shows promise in treating certain health conditions and there's some research to suggest that oral and topical use may help. However, data from high-quality clinical trials is lacking and more evidence is needed to confirm claims about malic acid and recommend its use.

Skin Care

Malic acid is an alpha hydroxy acid, which is said to be a natural exfoliator. It may be used to smooth wrinkles and fine lines, improve skin texture, cleanse pores, and improve overall skin. Because of this, various skin care products contain malic acid.

Malic acid also is used to balance skin pH. It is considered safe for use but can irritate skin in some people.4

Kidney Stones

Researchers have studied malic acid for its potential role in preventing and treating kidney stones, a common but painful condition that occurs when mineral deposits form in the urinary tract.

Malic acid is known to inhibit the development of kidney stones. The researchers concluded that malic acid supplementation might help treat calcium kidney stones. A 2024 study of malic acid, citric acid, and other components in an herbal tea made from Bryophyllum pinnatum leaves found it offered benefits in treating kidney stones.

The findings follow other studies that suggest benefits for kidney stones. A 2016 review on the importance of a healthy diet to prevent kidney stones suggested pears, which contain malic acid, could be a potential treatment option.

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