To determine the saponification value and ester value in oil, wax, and fat and the saponification value formula.
APPARATUS:
a). Heating Mantles Condenser supports.
b). Flask 250ml(Erlenmeyer)fitted with water cooled condenser.
c). Burette (Class A).
d). Volumetric Pipette-25ml (Class-A).
e). Dispensing device.
f). Analytical balance
REAGENTS & SOLUTIONS
b). Neutralized Ethanol (95%).
c). Sulphuric Acid 1N.
d). Phenolphthalein.
Saponification Value Procedure
a). Accurately weigh 1.0 gm of the sample into a 250 ml(Erlenmeyer) flask.
b). Using a Class A pipette, add 25ml of methanolic KOH.
c). Using a dispensing device, add 25ml of neutralized ethanol.
d.) Shake well the contents of the flask until all solid matter dissolves & place the flask on the heating mantle & place the condenser on the flask.
e). Reflux the contents for one hour.
f). Remove the flask from the heating mantle & add three drops of Phenolphthalein.
g). Titrate the hot solution with 1.0 N Sulphuric Acid with vigorous swirling until the pink color just disappears.
h.) Read the burette reading & record the ml of 1.0 N Sulphuric Acid used for each sample & blank.
CALCULATIONS
Saponification Value Formula
\[Saponification Value = {(Blank - Sample) * (Normality) * (56.1)} / Weight\]
PRECAUTIONS
a). The period for reflux should remain the same for each sample. You must write the proper period.
b). The amount of Sample should not exceed 1.5gm. This is the perfect quantity for determination.
c). The temperature should also remain constant and heating mantle should be of the same capacity.
  Method of Neutralization of Ethanol (95%)
1. Take Ethanol in a 250ml conical flask and add 2-3 drops of Phenolphthalein indicator.
2. Now take 0.1N aqueous KOH solution in a burette(Class A).
3. Now start adding 0.1N aqueous KOH solution through the burette to the 250ml conical flask till the content changes there physical appearance i.e. from colorless to faint pink.
ESTER VALUE TESTING METHOD
Ester Value formula = Saponification Value – Acid Value
>Sulphur Testing Process | Sulphur content test method
>Titer test | Determination of titer value of oils and fat
Determination of saponification value of Soap and fatty Acid
The saponification value is the number of milligrams of KOH required to saponify 1.0 grams of sample.
Scope:- This method applies to the fatty acid of all soaps and soap products containing synthetic detergents.
Apparatus
(i) Erlenmeyer flask, corning alkali resistant and Kimble resistant or equivalent to 250 or 300 ml.
(ii) Air condensers, minimum 650 mm long.
(ii) Water bath or a hot plate with variable heat control.
Solutions /Reagents
(a) Accurately standardized 0.5N HCL.
(b) Alcoholic KOH solution ( The make KOH solution, place a few gm (6-10) KOH in a 2- lit. flask and add from 1 to 1.5 liters of 96% ethyl alcohol and boil on a water bath under a reflux condenser for 30 - 60 min. Distilled and collect the alcohol. Dissolve 27 gm of KOH low in carbonate in 1.0 liter of the distilled alcohol, keeping the temp. below 15.5 C while the alkali is being dissolved. This solution should remain clear.
(c) Phenolphthalein Indicator.
The procedure of saponification value
Weight a sample of such size that it will yield 5.0 gm of fatty acids. The sample may be placed directly in the Stokes flask, extraction cylinder, or into a volumetric flask. If the latter, make up to volume with distilled water mix thoroughly, and transfer with a pipet a quantity such that it will yield 5. gm of fatty material into an extraction cylinder or Stokes flask.
Weight a fatty sample of such size that the back titration is 45 to 55% of the blank. This is usually 3.0 - 4.0 gm. Add 50 ml of the alcoholic KOH with a pipet and allow the pipet to drain for a definite period.
Prepare and conduct blank determinations simultaneously with the sample.
Connect an air condenser and boil gently but steadily until the sample is completely saponified. This usually requires 30 min. to not rise to the top of the condenser has cooled somewhat but not sufficiently to jell, wash down the inside of the condenser with a little distilled water. Disconnect the condenser, add 1.0 ml of indicator, and titrate with 0.5 N HCl until the pink color has just disappeared.
Calculation
Saponification Value = (titration of blank - titration of sample)*28.05 / weight of a sample