Abstract
The determination of fat in foods can be performed by the saponification method. The procedure of this method is as follows:
After the addition of 10ml. of 33% KOH solution and 40ml. of 96% EtOH to W g. of sample, the mixture is boiled for 30 min., then cooled, and the soap formed by the saponification is decomposed with 17 ml. of 25% HCI, and the free fatty acids are then extracted with 50 ml. of petroleum naphtha, and 25 ml. of this naphtha solution are titrated with a standard NaOH solution. When T is the volume of N/10 NaOH used for the titration, the fat content (%) can be calculated by the following formula:
T×284×2×1.04×100/W×10.000=5.907T/W For the determination in samples with high a starch content, KOH used for the saponification must be dissolved in EtOH.
