Effect Of Emulsifiers On Milk Fat Globule Membrane During Processing

As a functional biomolecule and a biologically active milk fragment beneficial to health,milk fat globule membrane have attracted many scientists' interests.Milk fat globule membrane(MFGM)is a natural emulsifier to ensure the physical stability of fat globules in milk.However,the MFGM was damaged to a great extent during the processing.The purpose of this research is to explore how to improve the stability of it in the process of processing.By comparing the microstructures,rheological properties and physical stability of MFGM in milk with food emulsifier and milk without food emulsifiers.Several commonly used food emulsifiers(lecithin,trehalose,xanthan gum,CMC,locust bean gum)were explored.Improving the stability of adipose globular membranes in the process of processing provide theoretical guidance for how to better retain MFGM in the process of processing,and provide new ideas for developing the nutritional and functional characteristics of it to a greater extent.By measuring the stability,the effect of emulsifier on the stability of fat globule emulsion under different processing conditions was studied.The processing conditions of HTST(72 ?-750C,15s20s)resulted in an increase in the stability index of the fat globule emulsion(from 5.9 to 34.8),and the decrease of stability.The addition of emulsifier significantly reduced the stability index of the fat globule emulsion.The better emulsifier was xanthan gum and trehalose.The effect of locust bean gum was worse,in which lecithin reduced by 25.5,trehalose reduced by 29.6,xanthan gum reduced by 31.6,locust bean gum reduced by 13.6,CMC reduced by 26.8.Under the condition of LTLT(62??65? 30min),the stability of emulsion was improved by adding emulsifier.The addition of emulsifier prevented the accumulation of fat globules and the rupture of fat globule membranes to a certain extent.Adding trehalose and lecithin:Trehalose 2:3 fat globule emulsion sample had better heat resistance effect,lecithin decreased by 0.02,trehalose decreased by 1.99,lecithin:Trehalose 3:2 decreased by 0.25,lecithin:Trehalose 2:3 decreased by 1.33.Under freezing conditions,the stability of different fat globule films was basically the same as time.Under acidic LTLT condition,the stability index of the fat globule emulsion added with lecithin decreased by 0.34 compared with that without adding.The emulsion added trehalose decreased by 1.15.The stability index of the fat globule emulsion added with lecithin:Trehalose 2:3 was higher and the stability was poor.It showed that the lecithin and trehalose did not have the effect of compound improvement under acidic LTLT condition.