Draw structures showing the reaction of glycerol with myristic acid to form the triglyceride trimyristin. Would you expect this triglyceride to be a fat or an oil?

Understanding the esterification reaction is central to grasping how glycerol and fatty acids come together to form triglycerides like trimyristin. An esterification reaction is a chemical process where an alcohol and a carboxylic acid combine to form an ester and water. This reaction typically requires an acid catalyst and heat to proceed.

In the synthesis of trimyristin, glycerol, which contains three alcohol groups, reacts with myristic acid, which has a carboxylic acid group. When they come together, each of the hydroxyl (-OH) groups from glycerol links with the carboxylic acid (-COOH) group of myristic acid. This connection releases a molecule of water and forms an ester linkage, known chemically as an ester bond. The reaction is as follows:
\[\begin{equation}3\text{ RC(O)OH } + \text{ HOCH}_2-\text{CHOH}-\text{CH}_2\text{OH} \rightarrow \text{ RC(O)OCH}_2-\text{CH(OOCR)}-\text{CH}_2\text{OOCR} + 3\text{H}_2\text{O}\end{equation}\]
Through this reaction, one molecule of glycerol and three molecules of myristic acid yield one molecule of trimyristin and three molecules of water. The esterification is a key reaction in creating a variety of fats and oils found in nature and in the food industry.

Fats are a form of lipids and are composed of glycerol and fatty acids. They are categorized as saturated or unsaturated based on the chemical structure of the fatty acids.

Saturated fats have fatty acid chains with no double bonds between the carbon atoms. These straight chains stack neatly and result in a solid structure at room temperature. Saturated fats are typically found in animal fat and are thought to contribute to increased cholesterol levels in the blood.

Unsaturated fats, on the other hand, have one or more double bonds in their fatty acid chains, which introduce kinks or bends preventing tight stacking. These loose arrangements make unsaturated fats liquid at room temperature, like vegetable oils. Unsaturated fats are further categorized into monounsaturated fats (with one double bond) and polyunsaturated fats (with multiple double bonds). These fats are considered more health-friendly as they can help to reduce bad cholesterol levels.

The two primary building blocks of fats are glycerol and fatty acids. Glycerol is a simple compound, also known as glycerine or propane-1,2,3-triol, and it features three hydroxyl (-OH) groups. Fatty acids have a long hydrocarbon chain which is hydrophobic (water-repelling) and a carboxyl (-COOH) group which is hydrophilic (water-attracting).

Glycerol can bond with up to three fatty acids to form a triglyceride, which is the main form of stored fat in animals and plants. The nature of the fatty acids (whether they are saturated or unsaturated) determines the physical properties of the resulting triglyceride. Since trimyristin is composed of glycerol and myristic acid, which is a saturated fatty acid, it is solid at room temperature. This composition defines trimyristin as a saturated fat.