Q. 15.24 - An Introduction to General, Organic, and Biological Chemistry

Question

Linoleic acid is an $18$-carbon unsaturated fatty acid with two double bonds that occur in many vegetable oils including safflower oil $(75\%)$ and poppyseed oil $(75\%)$. Draw the line-angle formula for glyceryl trilinoleate (trilinolein).

Step-by-Step Solution

Answer

Linoleic acid is an unsaturated fatty acid with 18 carbons that can be found in a variety of vegetable oils, including sunflower and poppy seed oil. 

Step 1: Introduction

• Lipids are hydrophobic esters of intermediate to long-chain fatty acids.
• Saturated and unsaturated fatty acids are the two forms of fatty acids.
• Unsaturated fatty acids have a long chain of carboxylic acids with double or triple bonds in their structure. 
• The fatty acid chain is said to be saturated when it contains all of the single bonds in its structure. 

Step 2: Explanation

• Fats, waxes, sterols, and triglycerides are examples of naturally occurring lipids. 
• Triglycerides are lipids that have glycerol linked to three fatty acids.
• Fats and oils are examples of triglycerides. 
• Long, unbranched carbon chains with a carboxylic acid group at one end make up fatty acids. 
• Unsaturated fatty acids have one or more carbon-carbon double bonds, whereas saturated fatty acids have only single carbon-carbon bonds.

Step 3: Determine the line-angle formula for glyceryl trilinoleate (trilinolein).

• Sunflower oil and poppy seed oil contain linoleic acid, an unsaturated fatty acid with 18 carbons. 
• Glyceryl trilinoleate (trilinolein) has the following line-angle formula: