Total fat determination in milk and by-products is of considerable relevance for the dairy industries, to estimate milk quality, define its commercial value, as well as highlight any alterations obtained by removing fat while selling it as whole milk. In whole milk, the quantity of fat contained has not been altered. In skimmed milk, the fat is practically removed.
VELP has used its almost 40 years of experience working closely with its customers, to develop analytical solutions to suit every need.
Today, VELP technologies enable easy and automated routine testings and provide accurate results in fat determination, as well as nitrogen/protein, non-casein nitrogen, whey protein, and lipid oxidation studies.
In this analysis, performed on cow whole milk samples, the results were obtained by integrating the SER 158 Automatic Solvent Extractor and the HU6 hydrolysis unit.
Preliminary hydrolysis is necessary to get a reliable total fat milk determination, compliant with most industrial methods and standards. A direct solvent extraction would not be enough because a part of the lipids is chemically bound to other sample components.
The preliminary hydrolysis process with 4 N hydrochloric acids enables fat molecules release, before proceeding with filtration and washing. Then, the hydrolyzed sample is ready to be transferred, within the same crucible, to the SER 158 Automatic Solvent Extractor for the final extraction process.
The results obtained with the analysis, are reliable and reproducible according to the expected values, with a low relative standard deviation. This means that the automatic solvent extractors of the SER 158 series are an accurate and precise solution for fat determination and extractable matter according to the Randall method.