Investigation On In Vitro Digestive Dissolution Characteristics Of Fat-soluble Vitamins In Phytosterols Oil Products

β-sitosterol and γ-oryzanol phytosterols conjugates can be used as texture agents to build a network structure,thereby producing margarine.But the impacts of phytosterols on the nutritional physiological properties including in vivo digestive dissolution characteristics of fat-soluble nutrients(such as VA,VE,p-carotene),still remains poorly understood.Therefore,we investigated the release characristics of three vitmins from phytosterols margarine through an in vitro digestion model in this paper,as well as clarified the sustained-release mechanism.Moreover,the influences of phytosterols oil products on the physiological nutrition function of rats were further exploredThrough in vitro digestion model,phytosterols margarine possessed obvious effects of sustained-release on three fat-soluble vitamins,and the effects enhanced with the increasing concentration of phytosterols.When phytosterols concentrations added from 0%to 8%,the release amount of VA,VE and β-carotene from margarine during 2h decreased by 44.20%,25.92%,25.02%,respectively.There was a difference in release rates among three vitamins,that was VE>VA>β-carotene.The release amounts of VE,VA and P-carotene from margarines containing 4%of phytosterols during 2h reached 46.53%,29.13%,26.02%respectively.Results of model fitting for Ritger-Peppas revealed that sustained-release complianced with non-Fick diffusion.Investigation on diffusion coefficient has shown that the concentrations of vitamins and phytosterols resulted in the difference of diffusivities,the higher the concentration of vitamins was,the faster the diffusion was;the higher the concentration of phytosterols was,the smaller the diffusion coefficient was.Three fat-soluble vitamins exhibited different diffusivities,that was VE>VA>β-carotene.At a 4%concentration of phytosterol,diffusion coeffcients of VE,VA,β-carotene were(3.49 ± 0.22)×10-5,(0.88 ± 0.06)×10-5,(0.49 ± 0.04)×10-5 mm2/s,respectively.Overall,the concentration gradient of fat-soluble vitamins and phytosterols were the driving forces of fat-soluble vitamins diffusion from margarine.Studies on erosion constant have shown that,as the’ concentration of phytosterol in margarine increased,the erosion constant decreased.It had reduced by 0.14h-1 during one month storage among margarine with 0%—8%of phytosterols.Erosion constant decreased with the prolongation of storage time.Margarine containing 4%of phytosterol storaged in one month showed an erosion constant which was 0.13h-1 larger than that storaged in three months.Erosion constant increased with the rising of storage temperature,compared with margarine storaged at 37℃,the erosion constant of margarine stogared at 4℃ reduced by 0.21h-1.Margarine adding different emulsifiers showed different erosion constants:distilled molecular glyceride<polyglycerol ester<Span 60<mono-di glyceride.Animal experiment results showed that body weight of rats in the experimental group,whose feed contained phytosterols margarine,were lower than that of control group,and the high-dose group showed the lowest weight,which indicated that increasing dose of phytosterols inhibited the accumulation of fat tissue.In addition,serum total cholesterol,triglycerides and LDL levels in rats all increased as the concentration of phytosterols reduced,which indicated the magarine had a good efficacy on anti-atherosclerosis.The other nutritional physiology results showed that phytosterols margarine will not have adverse effects on animal organisms.