The Preparation Of L-se-methylselenocysteine Solid Dispersion And Application In The Milk

L-Se-methylselenocysteine is a kind of organic selenium. It is a white crystallinepowder, with a garlic-like odour. It is solubled in water, slightly solubled in methanoland ethanol. It has antioxidant, anti-cancer, enhance immunity, prevention ofcardiovascular disease, detoxification, antiviral activity.The preparation process of the L-SeMC solid dispersion was optimizated. Thefactors which affected the stability were examined. The in vitro release of soliddispersion was investigated, and the formula was adjusted based on milk taste. Sothose can provide a reference for the development and utilization of selenium-richfoods. The main contents and results were as follows:The effects of L-SeMC and ninhydrin color reaction conditions were examined.The optimum reaction conditions were as follows: the phosphate buffer pH was8.0,heating time was15min, cooling time was15min, and the concentration of ninhydrinwas1.2%. L-SeMC concentration at19.2~38.5mg/L had good linear relationship (R2＝0.9972)．The average recovery was101.4%, RSD=1.6%(n=3). The results showedthat the stability of the high, medium and low concentrations in60min were good.The RSD of precision was less than5%.The internal emulsification condensation method, the saturated aqueous solutionof β-CD method and the melt method embedding L-SeMC were contrasted byL-SeMC loss rate (%). The melting method was choosed as the production method.The evenness was affected by binders ratio at most, melting temperature followed, thelast was binders and excipients powder proportion. The optimized processingparameters were got by the response surface optimization. The processing parameterswere binders and excipients powder proportion:5:4, binders ratio:2:5, meltingtemperature:100℃. Under the optimized technology the evenness reached2.25The solid dispersion X-ray diffraction results showed that L-SeMC hadcharacteristic diffraction peak in the28°; the carrier mixture had characteristicdiffraction peaks respectively in4°,9°,13°,22°; the characteristic diffractionpeaks of L-SeMC and carrier mixture also obvious in physical mixture; but in the solid dispersion the characteristic diffraction peak of L-SeMC disappeared, and thecarrier mixture characteristic diffraction peaks at22°was also split into three, itmeans L-SeMC as amorphous form dispersed in the carrier.The effects of relative humidity, temperature, light and oxygen were examined.The solid dispersion was more sensitive to temperature; followed by light impact,oxygen and humidity. So the solid dispersion should be packed by foil bag vacuum,storage at room or cold temperature. After3months of accelerated test, the seleniumretention rate in the solid dispersion was72%, only59%in the physical mixture.The pH of the artificial intestinal fluid was8.0. The positive phase dialysismethod was used to research release kinetics study of solid dispersion. The releasemodel of L-SeMC solid dispersion was matched with Retger-peppas equation:Q=32.60733t0.42344(R2=0.98669).The factors of L-SeMC solid dispersion which affect on taste were adjusted bysensory experiment. The optimized processing parameters were monoglycerides andsugar esters ratio:2:4, binders and excipients powder ratio:1:1, maltodextrin andβ-CD ratio:2:7. The evenness was3.26less than15. The stability results showed thatpacked Selenium-enriched milk was stored at room temperature for6months. Thedispersion, odor and taste remained good. After6months of storage the seleniumretention rate was95.4%.