The key difference between lactic acid and mandelic acid is that lactic acid is not suitable for sensitive skin, whereas mandelic acid is the best option for sensitive skin.
Lactic acid and mandelic acid have common application as an ingredient in skincare products. These two compounds can be applied to different skin types, which makes them different from each other.
CONTENTS
1. Overview and Key Difference
2. What is Lactic Acid
3. What is Mandelic Acid
4. Lactic Acid vs Mandelic Acid in Tabular Form
5. Summary – Lactic Acid vs Mandelic Acid
What is Lactic Acid?
Lactic acid is an organic compound having the chemical formula CH3CH(OH)COOH. In its solid state, this compound is a white powder, and it is miscible with water. Upon its dissolving in water, lactic acid forms a colourless aqueous solution. We can name it an alpha-hydroxy acid because it has a hydroxyl group adjacent to the carboxyl group. This compound is useful as a synthetic intermediate compound in some organic synthesis industries. It is also named milk acid because milk is rich in lactic acid.
The lactic acid compound is a chiral compound. It contains two enantiomers known as L-lactic acid and D-lactic acid. The racemic lactic acid is an equal mixture of these two enantiomers. This racemic mixture is miscible with water and ethanol.
Figure 01: The Chemical Structure of Lactic Acid
We can produce lactic acid through the fermentation of milk because milk is rich in lactic acid. Often, the product of this fermentation is racemic lactic acid. But some bacterial species solely tend to produce the D-lactic acid. However, the fermentation by anaerobic respiration in animal muscles forms the L-lactic acid. Therefore, this compound constantly is formed in animals from pyruvate during the action of the enzyme lactate dehydrogenase. This production can occur during normal metabolism and exercise.
There are pharmaceutical and cosmetic applications of lactic acid, which include the production of water-soluble lactates from insoluble active ingredients, as an ingredient in topical preparations and cosmetics for the adjustment of acidity, etc. Moreover, it has applications in cleaning products manufacturing because it is useful as a descaling agent for the removal of hard water deposits.
What is Mandelic Acid?
Mandelic acid is an organic compound having the chemical formula C6H5CH(OH)COOH. It is an aromatic alpha hydroxy acid. This compound occurs as a white crystalline solid substance that is soluble in water and polar organic solvents. This substance is a useful precursor to various drugs. Moreover, it occurs as a racemic mixture due to the chirality of the compound. We call this racemic mixture paramandelic acid.
Figure 02: The Chemical Structure of Mandelic Acid
We can produce this acidic compound by the acid-catalyzed hydrolysis of mandelonitrile. Mandelonitrile is the cyanohydrin of benzaldehyde. We can prepare mandelonitrile by reacting benzaldehyde with sodium bisulfite to give an adduct formed from mandelonitrile and sodium cyanide which we can then hydrolyze.
When considering the uses of Mandelic acid, it is used as an antibacterial agent for treating urinary tract infections, as an oral antibiotic, as a component in face peels, for the production of drugs such as cyclandelate and homatropine, etc.
What is the Difference Between Lactic Acid and Mandelic Acid?
Lactic acid and mandelic acid are organic compounds having acidic properties. These are useful ingredients in skincare products. The key difference between lactic acid and mandelic acid is that lactic acid is not suitable for sensitive skin types, whereas mandelic acid is the best option for sensitive skin when these compounds are used in skincare products. Moreover, lactic acid has an aliphatic structure, whereas mandelic acid has an aromatic structure.
The following infographic lists the differences between lactic acid and mandelic acid in tabular form for side by side comparison.
Summary – Lactic Acid vs Mandelic Acid
Lactic acid and mandelic acid have common application as an ingredient in skincare products. The key difference between lactic acid and mandelic acid is that lactic acid is not suitable for sensitive skin whereas mandelic acid is the best option for sensitive skin when these compounds are used in skincare products.
Reference:
1. “Mandelic Acid.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine.
Image Courtesy:
1. “7 Milchsäure” By Schemiker (talk) – Own work (Public Domain) via Commons Wikimedia
2. “Kwas migdałowy” By Arrowsmaster – Own work (Public Domain) via Commons Wikimedia