During their handling and processing, milk and dairy products are subjected to stringent analytical controls to guarantee their composition and quality.
Commission Regulation (EC) No 273/2008, of 5 March 2008, lays down parameters to determine the reference limits and methods for the chemical, physical and microbiological analysis, and for the organoleptic evaluation, of milk and dairy products.
It also states that other methods can be used, as long as they are properly calibrated and are regularly checked against the reference method. One of the determining parameters is fat content.
Fat content determination is of great importance because:
- This parameter impacts on the price paid per liter of milk.
- It is used to determine if a sample of milk or cheese complies with established legal values.
- It is necessary to know its value to classify the milk for the preparation of derivatives.
There are different methods for determining the content of fat in milk and cheese.
Two typical methods for determining the content of fat in milk and cheese are:
- Mojonnier method Is a gravimetric method that uses organic solvents to extract fat. Subsequently the solvent is evaporated and the fat is determined by weighing the dry fatty extract.
- Gerber method Volumetric method that uses chemical reagents (sulfuric acid, detergents) to achieve the breaking of the emulsion and the fat separation. Then the fat content is measured in a special flask (butyrometer).
PanReac AppliChem has the reagents required for these methods. In the table below you will find the reagents involved in these analysis depending on the type of sample (Milk or Cheese) and type of method used (Gravimetric (Mojonnier)) or Butyrometric (Gerber for milk or Van Gulik for cheese).
|Description||Order No.||Quantity||Gravimetric method||Butyrometer method||Gravimetric method||Butyrometer method|
|(ISO 1211)||(Gerber method) (ISO 2446)||(ISO 1735)||(Van Gulik method) (ISO 3433)|
|Ammonia 25% (as NH3) (Reag. USP, Ph. Eur.) for analysis||121129||1000 mL, 2.5L, 5L||x|
|Amyl Alcohol according to NF V 04-210 for analysis||125715||1000 mL||x|
|Diethyl Ether stabilized with ~6 ppm of BHT (Reag. Ph. Eur.) for analysis, ACS, ISO||132770||1000 ml, 2.5L, 5L||x||x|
|Ethanol 96% v/v for analysis, ACS||131085||1000 mL, 2.5L, 5L||x||x|
|Hydrochloric Acid 25% for analysis, ISO||133378||1000 mL, 2.5L, 5L||x|
|Isoamyl Alcohol according to Gerber for analysis||121079||1000 mL, 2.5L||x|
|Petroleum Ether 40-60°C for analysis, ACS, ISO||131315||1000 mL, 2.5L, 5L||x||x|
|Sulfuric Acid 90-91%
according to Gerber for analysis
|121010||1000 mL, 2.5L, 5L||x|
|Sulfuric Acid 62% (d=1,522) according to Van Gulik for analysis||173253||1000 mL, 5L||x|