Composition and Fatty Acid Distribution of Bovine Milk Phospholipids from Processed Milk Products

Abstract

The aim of this work was to assess the accuracy of different extraction methods of phospholipids and to measure the effect that processing has on phospholipid composition. Four methods of extracting phospholipids from buttermilk powder were compared to optimize recovery of sphingomyelin. Using the optimal method, the phospholipid profile of four dairy products (raw milk, raw cream, homogenized and pasteurized milk, and buttermilk powder) was determined. A total lipid extraction by the Folch method followed by a solid-phase extraction using the Bitman method was the most efficient technique to recover milk sphingomyelin. Milk processing (churning, centrifuging, homogenization, spray-drying) affected the profile of milk phospholipids, leading to a loss of sphingomyelin and phosphatidylcholine after centrifugation for cream separation. We also observed a corresponding decrease in the saturation content of the raw cream phospholipids, and a loss of phosphatidylethanolamine after spray-drying to produce buttermilk powder.

Comparison of dairy phospholipid preparative extraction protocols in combination with analysis by high performance liquid chromatography coupled to a charged aerosol detector

“…As mentioned (Section 3.1), this absence has been noted by other authors and has been associated with the presence of ammonia in the extraction procedure. The use of heat to evaporate the solvents also contributes to hydrolysis and oxidation of the PLs (Gallier, Gragson, Cabral, Jimenez-Flores, & Everett, 2010a). Hence, a cold extraction such as that provided by the Folch methodologies is preferred.…”

“…Aeration or agitation, such as that which occurs during the butter-making process, leads to emulsion inversion following complete disruption of MFGM. This creates a phase separation of lipids, butter, and water soluble components of the MFGM, which includes PLs, being recovered in the buttermilk (Gallier et al, 2010a(Gallier et al, , 2010b. Cold storage of cream (fat crystallisation) prior to agitation may also contribute to specific migration of PLs to the serum phase, buttermilk (Dewettinck et al, 2008).…”

“…Surface-bound MFGM material present in the milk is released into the serum or skimmed milk phase upon centrifugation (Gallier et al, 2010a;Gallier, Gragson, Jim enez-Flores, & Everett, 2010b;Plantz, Patton, & Keenan, 1973;. Aeration or agitation, such as that which occurs during the butter-making process, leads to emulsion inversion following complete disruption of MFGM.…”

β-Casein–phospholipid monolayers as model systems to understand lipid–protein interactions in the milk fat globule membrane

“…Buttermilk powder was provided by Land O'Lakes, Inc. (Arden Hills, MN, USA). The phospholipid mixtures from RM, RC, PM and BP were obtained as described in Gallier et al (2010a). The phospholipid extracts and the physical properties of the phospholipid monolayers were characterized in previous publications (Gallier et al, 2010a,c).…”

“…In this study, the partitioning of b-casein between the liquid-ordered and the liquid-disordered phases of supported monolayers of natural complex mixtures of phospholipids extracted from raw milk (RM), raw cream (RC), processed milk (PM) and buttermilk powder (BP) was examined after sub-phase addition of the protein. The mixtures of phospholipids from the four dairy products are representative of the phospholipid composition found in the milk fat globule membrane at different stages of milk processing (Gallier, Gragson, Cabral, Jiménez-Flores, & Everett, 2010a). It is essential to investigate if the proteins adsorb at the interface as a separate protein monolayer and therefore exist in protein domains without lipids, or if the proteins associate with the lipids and therefore penetrate the lipid domains.…”