Effect Of Interaction Between Functional Components And Milk Protein In Lipid-lowering Milk On Lipid-lowering Effect

Dairy products are an important part of the dietary nutrition structure of Chinese residents.They contain high-quality protein,various trace elements and biological active ingredients,including a variety of active ingredients for beneficial lipid metabolism,such as milk calcium,whey protein,polar lipids and Conjugated linoleic acid and the like.In addition,the dairy product is a high-quality carrier of the active ingredient,and the active ingredient contained in the milk can synergize with the post-added active ingredient to regulate the blood lipid or protect the added active ingredient,so the milk is often used to develop functional dairy products..However,the composition of the milk is complex,and the milk protein is susceptible to a variety of active ingredients,which has an unknown effect on the hypolipidemic effect.Basic research related to this aspect is still relatively lacking.Many of the lipid-lowering dairy products have unclear functions and inaccurate positioning,which has greatly affected people's acceptance of hypolipidemic dairy products.Therefore,this topic selects common polyphenols and dietary fiber to explore its effect on the ex vivo digestibility of milk protein;and the effect of milk protein and sterilization conditions on the bioavailability of polyphenols;in addition,the in vitro evaluation of hypolipidemic The method of ability to explore the effect of the interaction between the combination of lipid-lowering active ingredients added to the lipid-lowering milk and milk protein on its hypolipidemic effect.The main findings are as follows:1.The active ingredients with lipid-lowering ability are selected,which are polyphenols EGC and EGCG,and dietary fiber ?-glucans,all of which are 0-8.0 mg/m L.A mixed system with milk protein was prepared to study the effect of lipid-lowering active ingredients on the ex vivo digestibility of milk protein.The results showed that the three active ingredients all reduced the vitro digestibility of milk protein.When the EGC concentration was greater than 2.0 mg/m L,the ex vivo digestibility of milk protein decreased significantly.When the concentration of EGCG was greater than 0.5 mg/m L,the protein The in vitro digestibility was significantly reduced,indicating that EGC is more suitable as an active ingredient added to dairy products than EGCG.2.The milk-polyphenol(EGC)and milk protein-polyphenol(EGC)simulated mixed system were prepared,and the milk base was heated and mixed with polyphenols,and the milk base and polyphenol were mixed first and then heat-sterilized.In this way,the effects of milk protein and pasteurization conditions(heating)on the bioavailability of EGC were explored.The results show that at room temperature,the combination of milk protein and EGC will reduce the content of free EGC.Under pasteurization conditions,the content of EGC in each sample was significantly lower than that of the control group.Under the method of mixing polyphenols after heating the milk base,the EGC content of the casein-polyphenol simulation system group is 9.57% higher than that of the common heating mode;the milk-polyphenol group is 10.7% higher than the common heating mode.Explain the effects of different heat treatment sequences on the bioavailability of polyphenols.The heating of the milk base can reduce the loss of polyphenol activity.After the simulated digestion,the EGC content in the casein-polyphenol mixed system It should be higher than the control group,in which the milk base was mixed with polyphenols after heating treatment,which was higher than 22.4% of the control group,and was 7.8% higher than the control group under the common heating mode.It is shown that casein can protect the activity of EGC during the simulated digestion process.3.Taking the lipid-lowering active ingredients EGC,oat ?-glucan and phytosterol ester commonly used in blood fat-lowering cow milk as the research object,the effects of the interaction of active ingredients and milk proteins on the blood lipid-lowering ability of the active ingredients in vitro were investigated.The results showed that whey protein and casein can reduce the inhibitory effect of lipid-lowering active ingredients on pancreatic lipase activity,reduce its antioxidant capacity and inhibit the solubility of cholesterol micelles,indicating that the active ingredients in milk fat-reducing milk and milk protein interact with each other.The effect will affect its ability to lower blood fat.In addition,the active ingredient mixture better maintains its ability to lower blood lipids after interaction with milk proteins than a single functional ingredient.