Petroleum ether 40-60 °C, 25 l, tinplate

Acid Value Determination

The acid number characterises the acidic components of the fats. For this purpose, the sample is dissolved in a solvent and titrated against phenolphthalein with potassium hydroxide solution. Only free fatty acids are recorded. The fatty acids bound in the glycerides are not determined.

Determination of Fat

Fat analysis is used to determine the fat content and fat composition of foodstuffs. Individual components or total fats levels can be calculated depending on the purpose of testing. Different components are subject to different procedures by law, such as the Gerber method or the Van Gulik technique.

• Add sample to 60 ml water

• Subsequently add, while mixing after each step:

a) 5 ml Carrez-I-solution, Art. No. 9944

(or 7,2 g zinc sulphate heptahydrate, Art. No. K301 ad 100 ml)

b) 5 ml Carrez-II-solution, Art. No. 9950

(or 3,6 g potassium hexacyanoferrate(II), Art. No. P745 ad 100 ml)

• Adjust pH to 7,5 - 8,5 by adding NaOH (0,1 M) Art.No. K020

• Fill volumetric flask up to mark, mix, and filter