Extraction And Microcapsule Preparation Of Anthocyanin From Lycium Ruthenicum Murr

Lycium ruthenicum Murr contains abundant anthocyanins.Anthocyanin has the functions of anti-oxidation,anti-radiation,anti-inflammation,anti-aging and lowering blood lipid,etc.It has a broad application prospect in the food industry.However,the stability of natural anthocyanins is poor,resulting in certain limitations in the application of food.Anthocyanin stability is affected by a number of environmental factors,such as pH,light,temperature,oxygen,and enzyme activity.How to improve the stability of anthocyanins during processing and storage has become a challenge for the application of anthocyanins in the food industry.Microencapsulation technology can protect anthocyanins and improve their stability.In this paper,anthocyanins were extracted from Lycium ruthenicum Murr by double hydro-ultrasonic technology and microcapsules were prepared by spray drying.The effects of different wall materials on microcapsules were studied,and the most suitable wall materials for microcapsules of Lycium ruthenicum Murr anthocyanin were selected.The preparation technology of microcapsules was optimized,and the physical and chemical properties of microcapsules were analyzed.The main findings are as follows:(1)Lycium ruthenicum Murr was used as raw material to extract anthocyanins by double aqueous phase-ultrasonic method and optimize the process,and to study the antioxidant capacity of sorghum anthocyanins.Response to surface analysis was used to study the effect of the interaction of the respective variables on the anthocyanin content.The antioxidant capacity was studied by using DPPH removal efficiency as an evaluation index.The optimum conditions for anthocyanin extraction were ethanol mass fraction of 26%,ammonium sulfate mass fraction of 21%,extraction time of 36 min,extraction temperature of 56 ?,and anthocyanin content of 17.98 mg/g.However,the anthocyanin content extracted by conventional acidification ethanol method was 13.86 mg/g.The extraction effect of dual aqueous phase-ultrasonic method is better than that of traditional acidification ethanol method.In addition,the anthocyanins extracted by the dual aqueous phase-ultrasonic method had fewer impurities and higher purity.The IC50 of anthocyanins and BHT were 0.394 mg/m L and 1.282 mg/m L,respectively.An-thocyanins had better DPPH scavenging effects than commercial antioxidants(BHT).In summary,the two-aqueous phase-ultrasonic method can improve the extracting amount and reduce impurities.Anthocyanins have strong antioxidant capacity and are better than commercial antioxidants(BHT).It provides a new extraction method for the extraction of Lycium ruthenicum Murr.(2)In order to improve the stability of anthocyanin from Lycium ruthenicum Murr,the wall materials used for the microcapsules most suitable for scutellarin were screened.Using spray drying method,taking black anthocyanin as core material,glutinous rice starch(RS),modified glutinous rice starch(MRS),modified starch composite maltodextrin(MRS-MD),modified starch composite gelatin(MRS-GL),modified starch composite gum arabic(MRS-GA)for the preparation of five kinds of microcapsules for wall materials.The effects of different wall materials on microcapsules were analyzed by measuring the microcapsule embedding efficiency,studying storage stability,observing appearance and simulating gastrointestinal digestion.The results show that different wall materials can affect the embedding efficiency,storage stability,appearance and morphology and sustained release characteristics of microcapsules.The embedding efficiency of microcapsules with MRS-GL as the wall material is the highest(83.7%);the degradation rate of microcapsules with MRS-GL and MRS-GA as the wall material is relatively small and conforms to the secondary degradation kinetic model,and their storage stability good and can effectively prevent the influence of external environmental factors on anthocyanins;some microcapsules with MRS-GL,MRS-GA,and MRS-MD as wall materials appear as smooth spheres;and MRS-MD can improve flowers The bioavailability of anthocyanins reduces the degradation of anthocyanins by intestinal fluid,which can ensure its absorption and utilization in the human body.There is a certain correlation between the appearance and appearance of microcapsules,the efficiency of embedding efficiency and the stability of particles.(3)Meanwhile,embedding rate,DPPH scavenging activity,anthocyanin content and water activity were used as evaluation indexes to optimize the spray drying process of microcapsule.Besides,physical and chemical properties of microcapsules were analyzed,such as the structure,crystallinity,surface morphology and thermal properties of microencapsulated particles were comprehensively studied by means of infrared spectroscopy,X-ray diffraction,scanning electron microscopy and DSC.It was found that the best preparation technology of microcapsule was as follows: wall material concen-tration 6%,temperature 157 ?,injection pump speed 6%.Under this condition,the embedding rate,DPPH clearance rate,anthocyanin content and moisture activity of the microcapsule were 93.4%,45.41%,63.01 mg/L,and 0.49,respectively.The core material was successfully embedded in the middle wall of the microcapsule,and the starch-anthocyanin-gelatin polymer was formed.Microencapsulation is an effective technique to improve the stability of anthocyanin,which provides some references for the application of anthocyanin in food industry.