Lipid rafts may affect the coalescence of milk fat globules through phase transition after thermal treatment

This study aimed to investigate changes of fat globules and their membranes, and further analyze evolution of lipid profile of lipid rafts in membranes during heat processing of cow milk. Size of fat globules increased from 3.16 mu m to 3.70 mu m and zeta-potential decreased from -0.53 mV to -0.38 mV after thermal treatment, suggesting that fat globule membrane was destroyed and fat globule occurred coalescence. Glycemphospholipids and cholesterol in fat globule membrane decreased while sphingomyelin increased after thermal treatment. Results of lipidomics show that total of 38 species of 5 lipids molecule showed ability to differentiate the samples. At high temperatures, highly unsaturated glycerophospholipids and sterol lipids were lost from rafts, meanwhile, sphingomyelin and ceramide increased in this region. Significant change of lipid profile in the raft region during thermal treatment suggested a potential relationship between lipid rafts and fat globule coalescence behavior.

Automated summary

This study investigated changes in fat globules and their membranes during heat processing of cow milk. The study found that the size of fat globules increased and their membrane was destroyed, leading to coalescence. Additionally, the study showed that phospholipids and cholesterol decreased while sphingomyelin increased after thermal treatment. Furthermore, lipidomics analysis revealed significant changes in the lipid profile of the raft region, suggesting a potential relationship between lipid rafts and fat globule coalescence.