Soap is produced by a saponification or basic hydrolysis reaction of a fat or oil. Currently, sodium carbonate or sodium hydroxide is used to neutralize the fatty acid and convert it to the salt. Introduction Types of Soap Contributors. Although the reaction is shown as a one step reaction, it is in fact two steps.
The difference in solubility along the molecule enables its cleaning ability. In water, the long carbon chains of the soap molecules will be attracted to one another and reorganize to avoid the polar water molecules.
This orients the polar carboxylate heads towards the water molecules, forming a spherical structure known as a micelle. The center is hydrophobic, and the exterior is hydrophilic, allowing micelles to be soluble in aqueous solutions.
The micelle properties of soap are essential to its cleaning ability. Simply rinsing grease or oil off a surface cannot remove it.
This is because grease is hydrophobic and not water-soluble. However, when soap is used, the grease enters the interior of the micelle. The exterior of the micelle is hydrophilic, so it can be rinsed away with water. A significant drawback to soap is its intolerance to hard water. Hard water is an aqueous solution containing magnesium, iron, and calcium ions in the form of minerals.
In the presence of metallic cations, soap molecules will interact with the molecules and cause them to fall out of solution, forming a salt precipitate more commonly referred to as soap scum.
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Show More. Views Total views. Actions Shares. No notes for slide. Lipid hydrolysis 1. Hydrol ysis 2. Lipids give flavor and taste to the foods, and also serve as a heat transfer medium. E Chervreul who found that fats and oils consisted of esters of fatty acidsand glycerol.
The industrial lipid processing started in the middle of the 19th century. The production of margarine was developed in the beginning of the 20th century. Chemical analysis of fats and oils is done using a procedure years old but the modern lipid analysis started by introduction of gas-liquid chromatography and 20 yearslater of HPLC.
Hydrolysis is the breakdown of a substance by the addition of water. Fats and oils are hydrolyzed by moisture to yield glycerol and 3 fatty acids. This leads to hydrolytic rancidity of food product characterized by unpleasant flavor and aroma thereby making it undesirable forconsumers. Chemically fats are esters, so they are liable to hydrolysis. This reaction is catalyzed by lipase enzyme or can occurvia non-enzymatic hydrolysis. Partial hydrolysis of triglycerides will yield mono- and di- glycerides and free fatty acids.
Complete Hydrolysis Partial Hydrolysis 8. When hydrolysis is carried to completion with water in the presence of an acid catalyst, the mono-, di-, and triglycerides will hydrolyzeto yield glycerol and freefatty acids. With aqueous sodium hydroxide, glycerol and the sodium salts of thecomponent fatty acids soaps areobtained.
Types of Foods prone to lipid instability issues eEdible oils Shortening such as margarine and butter Fried foods such as potato chips, Essential oils e. Acid Value: It is defined as the amount mg of KOH required to neutralize the fatty acids in 1 gram of fat. FFA are fatty acids which havebroken away from oil moleculesor triacylglycerols. However, before their assimilation by bacteria, they need to be degraded. The degradation of lipids such as triglycerides is accomplished by extracellular hydrolyzing enzymes, called lipases esterases , that cleave the ester bonds in this molecule by the addition of water to form the building blocks glycerol an alcohol and fatty acids.
In this experimental procedure, tributyrin agar is used to demonstrate the hydrolytic activities of the exoenzyme lipase. The medium is composed of nutrient agar supplemented with the triglyceride tributyrin as the lipid substrate. Tributyrin forms an emulsion when dispersed in the agar, producing an opaque medium that is necessary for observing exo- enzymatic activity.
Following inoculation and incubation of the agar plate cultures, organisms excreting lipase will show a zone of lipolysis, which is demonstrated by a clear area surrounding the bacterial growth. This loss of opacity is the result of the hydrolytic reaction yielding soluble glycerol and fatty acids and represents a positive reaction for lipid hydrolysis.
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