Reichert-Meissl number

Volatile Acid Number. The volatile acid number or the Reichert-Meissl number denotes the number of c.c. of N/10-alkali required to neutralise the volatile acids, soluble in water, obtained from 5 grams of butter fat, previously melted and filtered. It is determined exactly as described in flit- chapter headed Tatty Substances (Vol. I, p. 377). 

Reichert-Meissl number. A measure of volatile, soluble fatty acids derived under arbitrary conditions. 

Oleomargarine and other butter-substitutes are made from mixtures of animal and vegetable oils. The olein from tallow, lard, or cottonseed oil is frequently used. These are colored and mixed with a small proportion of butter, or churned with milk in order to give the product the appearance and taste of butter. Oleomargarine can be distinguished from butter by the determination of the Reichert-Meissl number of each. That of the former is seldom more than 1, while that of butter is from 22 to 30. 

The concentration of butanoic add in milk fat is the principle of the widely used criterion for the detection and quantitation of adulteration of butter with other fats, i.e. Reichert Meissl and Polenski numbers, which are measures of the volatile water-soluble and volatile water-insoluble fatty adds, respectively. 

Cocoa fat and lipids In AOAC methodologies, the composition of fat and fatty acids in cocoa fat extracts are analyzed and characterized by physicochemical methods, including refractive index, melting point, saponification value and unsaponifi-able material, iodine number, Reichert-Meissl and Polenske values. 

Reichert-Meissl value n. The number of ml of MIO potassium hydroxide solution required to neutralize the free volatile and soluble fatty acids in 5g of the sample under test. 

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