Malic acid is a natural organic acid molecular formula is C₄H₆O₅ found in certain fruits and vegetables, especially green apples, of which it was named. It belongs to the family of α-hydroxycarboxylic acids since both the hydroxyl and its carboxyl are bonded to the same carbon atom. It is mainly used as a food additive. It occurs in apple and hence its name ( L. malus, apple).
Preparation of Malic Acid.
Preparation from Maleic acid. Maleic acid (obtained from benzene) upon treatment with hot dilute sulphuric acid under pressure gives malic acid.
Preparation from Succinic Acid. Careful monobromination of succinic acid and subsequent treatment with moist silver oxide forms malic acid.
Properties Of Malic Acid.
Physical Properties Of Malic Acid. Malic acid forms colorless crystals, mp 100°C, having a sour taste. It is very soluble in water and alcohol; slightly soluble in ether. It contains an asymmetric carbon atom and shows optical isomerism, the natural product is laevorotatory.
Chemical Properties Of Malic Acid. Malic acid is secondary alcohol and a dicarboxylic acid and gives reactions accordingly.
(1) Reduction. When reduced with Hl, it yields succinic acid.
(2) The action of Heat. Malic acid, when strongly heated, splits out a molecule of water from adjacent carbons to yield maleic acid and fumaric acid.
At 300°C, fumaric acid rearranges to give maleic acid which dehydrates to maleic anhydride.
Uses of Malic Acid.
Malic Acid is used.
- As acidulant in soft drinks and food-stuffs.
- In medicine as purgative and as a remedy for sore throat.
- When applied to the skin, malic acid is said to reduce the signs of aging, remove dead skin cells, help in the treatment of acne and promote hydration of the skin.
- Malic acid is also used to increase sporting performance when taken as a supplement. Sometimes it is combined with creatine supplements to improve the absorption of creatine from the body. Proponents claim that malic acid can promote energy production, increase exercise resistance and help fight muscle fatigue.
Malic Acid Benefits.
Skin pH Balance and Hydration.
Malic acid is also a humectant. Helps moisture retention to help your skin stay hydrated.
A 2014 study on aloe vera hydrating effects used malic acid, glucose and a chemical compound in aloe vera (acemannan) as indicators for fresh gel. Another small study also saw improvements in scales from old wounds following the application of malic acid and vaseline ointment, according to the National Institutes of Health (NIH).
You knew; A healthy pH level for the skin should be slightly acidic. Try to keep your skin’s pH level around 4 5 to 5. 5. Malic acid is often used as a component of cosmetics to balance pH levels. According to Bartek, a manufacturer that manufactures cosmetics and chemicals, malic acid is more balanced than other fruit acids. It has a better buffer capacity than other AHAs such as citric and lactic acid.
The better memory capacity means you can use more malic acid without overturning acidic skin balance or pH levels. If your skin’s pH level is unbalanced, then your skin’s protective barrier can become destabilized and more prone to dryness or acne.
Cleans and revitalizes the skin.
The malic acid in skin care products is celebrated for its ability to brighten the skin and smooth its texture. That’s why it’s a common ingredient in anti-aging creams.
According to a brain-skin binding study, higher stress can exacerbate skin conditions such as eczema, acne and premature aging. And while wine can help reduce stress, the external use of malic acid may be healthier.