Routine Determination of Milk Fat Composition for Nutritional and Technological Purposes

Abstract

78 individual milk samples (IS) were taken in the Czech Fleckvieh and Holstein dairy cow herds and 33 bulk milk samples (BS) were taken in 13 Holstein dairy cow herds to compare two methods for the determination of fatty acids (FAs) – routine/indirect (infrared (IR) spectroscopy, MIR-FT) and reference/direct (gas chromatography, GC). The IS results show that the fatty acids C16:0 and C18:1 and the group of saturated (SFA) and unsaturated (UFA) FAs can be determined using routine method with a relatively high reliability (correlations (r) 0.7543, 0.7607, 0.8424 and 0.9492; P < 0.001). In case of polyunsaturated FAs is the r lower (0.2891; P < 0.05). In BS the tightness of relations is stronger in the case of the SFA and UFA (r 0.7094; 0.9389; P < 0.001), while for the group of TFA (trans isomers of unsaturated FAs) and PUFA (polyunsaturated FAs) are lower r (0.5897 and 0.5931; P < 0.001 respectively). Routine method for fatty acids profile determination is efficient for selection of raw milk to guarantee the production of specific dairy products with increased content of healthful fatty acids.

Keywords

• dairy cow
• milk sample
• gas chromatography
• infrared spectroscopy
• analytical result reliability
• correlation