What is saponification of fats

Fatty acids made up of ten or more carbon atoms are nearly insoluble in water, and because of their lower density, float on the surface when mixed with water. Unlike paraffin or other alkanes, which tend to puddle on the waters surface, these fatty acids spread evenly over an extended water surface, eventually forming a monomolecular layer in which the polar carboxyl groups are hydrogen bonded at the water interface, and the hydrocarbon chains are aligned together away from the water.

This behavior is illustrated in the diagram on the right. Substances that accumulate at water surfaces and change the surface properties are called surfactants. Alkali metal salts of fatty acids are more soluble in water than the acids themselves, and the amphiphilic character of these substances also make them strong surfactants.

The most common examples of such compounds are soaps and detergents, four of which are shown below. Note that each of these molecules has a nonpolar hydrocarbon chain, the "tail", and a polar often ionic "head group". The use of such compounds as cleaning agents is facilitated by their surfactant character, which lowers the surface tension of water, allowing it to penetrate and wet a variety of materials.

Very small amounts of these surfactants dissolve in water to give a random dispersion of solute molecules. However, when the concentration is increased an interesting change occurs. The surfactant molecules reversibly assemble into polymolecular aggregates called micelles.

By gathering the hydrophobic chains together in the center of the micelle, disruption of the hydrogen bonded structure of liquid water is minimized, and the polar head groups extend into the surrounding water where they participate in hydrogen bonding.

These micelles are often spherical in shape, but may also assume cylindrical and branched forms, as illustrated on the right. Here the polar head group is designated by a blue circle, and the nonpolar tail is a zig-zag black line. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products.

List of Partners vendors. Share Flipboard Email. Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph. She has taught science courses at the high school, college, and graduate levels. Facebook Facebook Twitter Twitter. Updated January 08, Key Takeaways: Saponification Saponification is the name of the chemical reaction that produces soap. In the process, animal or vegetable fat is converted into soap a fatty acid and alcohol.

The reaction requires a solution of an alkali e. The reaction is used commercially to make soap, lubricants, and fire extinguishers. Featured Video. The experiment was repeated using microwave.

The corresponding efficiencies and energy consumptions were calculated. As a result of the Saponification process, the fatty acids are hydrolyzed in presence of an alkali so as to form salts of alkali and alcohol. Upon cooling of the dissolved mixture, solid soap was observed the end of the process. Energy consumed by each process is tabulated below. One way to test the formation of soap is by dissolving the solid in water and checking foam formation. It can also be confirmed by performing pH test, which involves dissolving the soap in a freshly prepared water and isopropyl alcohol mixture.

The dissolved soap solution can be tested with phenolphthalein indicator and the soap formation is indicated by the color of the solution. A dark pink and clear solution indicates presence of excessive caustic solution, the one with colorless or yellowish clear solution indicates a fairly neutral pH, hazy solution indicates untreated oil, hazy and pink solution indicates the reaction was complete.

A clear, pale pink solution indicates good results. Figure 9. Table 4. The energy consumed for saponification of 10g of animal fat. The Saponification process using conventional heating took four times as much time to complete than the microwave process, and consumed more energy.

The quality of soap was also tested. From the Fig. In Fig 9 b we see a hazy pink solution with yellow droplets in it, indicating the presence of unreacted oil. The solution also appears dark in color indicating the presence of excessive caustic soda.