The key difference between palmitic acid and stearic acid is that palmitic acid is more cholesterol-raising than stearic acid.
Palmitic acid and stearic acid are the most commonly consumed saturated fatty acids in the Western diet, but they also can contribute to the raising of cholesterol levels in our body.
CONTENTS
1. Overview and Key Difference
2. What is Palmitic Acid
3. What is Stearic Acid
4. Palmitic Acid vs Stearic Acid in Tabular Form
5. Summary – Palmitic Acid vs Stearic Acid
What is Palmitic Acid?
Palmitic acid can be described as a type of saturated fatty acid having the chemical formula C16H32O2. Another name for this compound is hexadecanoic acid. Palmitic acid is the most common saturated fatty acid that occurs in animals, plants, and microorganisms. It mainly occurs as a component in the oil taken from the fruit of oil palms, which makes up about 44% of total fats. Further, food sources such as meat, cheese, butter, and other dairy products also contain palmitic acid, around 50-60% of total fats. Furthermore, palmitates can be described as the salts and esters of palmitic acid.
Figure 01: Palmitic Acid
The molar mass of palmitic acid is 256.43 g/mol. This substance appears as white crystals. Palmitate anion can be described as the observed form of palmitic acid at pH 7.4, which is the physiological pH level.
When considering the applications of palmitic acid, it is useful as a surfactant agent to produce soap, cosmetics, industrial mold release agents, etc. The form of palmitic acid used in these applications is sodium palmitate. Sodium palmitate can be obtained through the saponification of palm oil. Moreover, its inexpensive nature makes it a good choice for the food industry to add texture and mouthfeel to processed food.
What is Stearic Acid?
Stearic acid can be described as a saturated fatty acid having the chemical formula C17H35CO2H. This compound has a carbon chain with 18 carbon atoms. The IUPAC name of stearic acid is octadecanoic acid. It appears as a white waxy substance. The salts and other derivatives of stearic acid are named stearates. Stearic acid has a pungent oily odor.
Figure 02: Stearic Acid
We can obtain this acid through the saponification of fats and oils. The triglycerides in the fat and oil undergo saponification in the presence of hot water. The resultant compound mixture should be distilled to obtain pure acid. However, commercially available stearic acid is actually a mixture of stearic acid and palmitic acid.
When considering the uses of stearic acid, it is important as a surfactant and as a softening agent due to the presence of a polar head group that can get attached to metal cations. It also has a nonpolar chain, which makes it possible to dissolve in organic solvents.
What is the Difference Between Palmitic Acid and Stearic Acid?
Palmitic acid and stearic acid are very important organic compounds. These are the most commonly consumed saturated fatty acids in the Western diet. The key difference between palmitic acid and stearic acid is that palmitic acid is more cholesterol-raising than stearic acid. The chemical formula of palmitic acid is C16H32O2, and the chemical formula of stearic acid is C17H35CO2H.
The below infographic presents the differences between palmitic acid and stearic acid in tabular form for side-by-side comparison.
Summary – Palmitic Acid vs Stearic Acid
Palmitic acid is a type of saturated fatty acid having the chemical formula C16H32O2, while stearic acid is a saturated fatty acid having the chemical formula C17H35CO2H. These are the most commonly consumed saturated fatty acids in the Western diet. The key difference between palmitic acid and stearic acid is that palmitic acid is more cholesterol-raising than stearic acid.
Reference:
1. “Stearic Acid.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine.
Image Courtesy:
1. “Palmitic acid” By BartVL71 – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Stearic-acid-3D-Balls” By Matt18224 – Own work (CC0) via Commons Wikimedia