| The paper has carried out the native ghee purification and its comprehensive utilization research completely.In this article,a new technics was founded using the protein and fragrance material of the native ghee fully in order to avoid the environment pollution caused by the waste which is produced in the traditional technics process.At the same time,we deeply studied butter monoglyceride - diaceltyl tartaric acid ester of monodiglyceride(DATEM)-casin Tibet ghee microcapsule emulsified system and found that the emulsified liquid prepared by this system was stable,and there was no reformation(O/W→W/O)in the spray-drying process,and had no emulsion breaking phenomenon even in the high concentration common-salt(5%)and high consistency tea juice(including 1%substance distilled from black tea).Because of the reason why the malt dextrin(or corn syrup)wall material used to produce the traditional pulverous grease could cause cavities and cracks phenomenon when spray-drying,we refered a assumption of appending sele-reparing substances in the malt dextrin(or corn syrup).What's more,three samples were made already,and it is hopeful that they will be used in the manufacture of Tibet ghee powder after we gave them a elementary research including their character,performance,dosage and so on.By researching and optimizating Tibet ghee microencapsul technology,we knew the appropriatest parameters such as the temperature of ghee emulsion (70-75℃),the homogeneous pressure(35～40Mpa),the temperature of entering wind(160-190℃)and emerging wind(90-100℃)in the spray- drying process.we also investigated the ghee'granularity by Laser particle analysis.By investigating the ghee microcapsules' quality,the results showed that:the oil amount on the surface was in low(1.52%),but had a high rate of embedded(96.6 percent),the powder was exquisite and uniform,its color was ivory,the smell was pure,with a little ghee's aroma.During 200 days storage time the changes of peroxide value and acid about the ghee and the ghee microcapsule products showed that:the peroxide value in the 200 days was from rosing to dropping and rancidity had happened and had la taste.But ghee powder which dealed with microcapsule had little rise during those days.The truth which acid value of ghee rose 19.21 units and the ghee microcapsule product only rose 5.30 units indicated that ghee microcapsules had a long life because the propertie of microcapsules' film material was so good that they can protect the core material of ghee effectively for stopping contacting with the oxygen,water and others in the air.Elements analysis had been conducted and it was not difficult to find the nutrient contents in the ghee and the ghee microcapsule were abundant.Several ways were adopted to detect the elements including in the perfume which volatilizezing form ghee and the results showed there wre 52 kinds of compounds in it.These detecting methods were headspace sample,ghee direct sample and using the steam to distill the ghee fragrance and then united them with gas chromatography-mass spectrum.By using the infrared spectrometry to investigate the interaction between protein and carbohydrate in the process of forming the micro capsule wall structure, it finally indicated:the association function exists between the protein molecule and the environmental dextrin's hydroxyl,which is goog for maintaining the integrity of the microcapsule structure;but as to mcro-encapsuled ghee,the infrared characterful peaks did not change,which showed that it had little effect on the core material,for another word,its primary features were maintained.We choosed isothiocyanate-fluorescein as a fluorescent probe,and used it to mark casein protein in alkaline conditions,and used UV and fluorescence spectrometry to study the spectrum changes of interactions between the casein protein which is marked or not marked and fluorescein isothiocyanate,And adopted a confocal laser scanning microscope to scan the ghee microcapsules which was marked,the results showed that:the probe was a very good one.Green fluorescence is found between the core material and the wall material and the microcapsule surface,so we could conclude that the casein protein assembled in the membrane surface of oil-water interface and micro-capsules.Using the scanning electron microscope and confocal laser scanning microscope,we could get the ghee microcapsule apparent morphological analysis result,which indicates the microcapsule surface is smooth,dent,cavity, intact,crack,and had no corrugation,and the wall structure was compact.At the same time,the microcapsule ghee interior ultra structure which had two forms,namely single nucleus and the polynuclear which could be detected through confocal laser scanning microscope.Through atomic force microscope determination we got the ghee microcapsule's roughness was 7.651-8.693 nm.By using emulsion-solvent-difusion to preparate ghee-PLGA nano-capsules,the average particle diameter was 0.20μm,the first diameter was 77-100 nm.Increasing the ghee's amout was good to raising oil content of core material;Increasing the PLGA's amout and the concentration of polymer led to bigger capsule size.Under the premise of guaranteeing the ghee embedding rate,we try our best to increase the proportion of the oil phase in order to obtain smaller particle size.Bigger domestic water phase may lead to the ghee diffuse from inter- emulsification,and then embedding rate was reduced.Along with the enlargement of the water volume,the capsule granularity would increase.The infrared spectrum of PLGA analysis indicated that oxygen atom in the C=O groups formed hydrogen bond with the carboxyl ghee and polyvinyl alcohol of the side-hydroxy to make PLGA's C=O stretching vibration absorption displaced.The ghee which was mainly wrapped in the nanometer capsule to form shell structure. The nano-capsules was mainly to form anti-micelles and there were at least three kinds of water in them,such as bounding water,free water and free moisture, moreover,the proportion of them would change along with the reaction parameter changing. |
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