Placing pasteurisation before or after microfiltration impacts the protein composition of milk fat globule membrane material

Abstract

Milk fat globule membrane (MFGM) is a value-added ingredient with numerous applications. During industrial isolation, the choice of processing steps is known to influence the intactness and bioactivity of the resulting MFGM-containing material. The present study demonstrates that pasteurisation at 80, 85 or 88 °C had a different impact on the protein composition of MFGM material, depending on whether it was performed before or after microfiltration of raw milk. MFGM isolates from milk pasteurised before microfiltration had a significantly higher content of β-lactoglobulin, but a lower level of periodic acid Schiff base 6 and 7, compared with MFGM isolated from milk pasteurised after microfiltration. The β-lactoglobulin content in MFGM material increased progressively with pasteurisation temperatures. Pasteurisation after filtration did not alter the protein composition of MFGM material significantly compared with an unpasteurised control. The results point towards improved process requirements for a more gentle isolation process for MFGM-enriched fractions.