Research On The Palm Oil Microcapsule Technology And The Character Of The Microcapsule

The microencapsulated powder of palm oil was prepared by using soybean proteinisolation and maltodextrin as wall materials and different melting point palm oil as corematerials in this article. The process was realized by spray drying, the preparation conditionsof emulsion and factors that influence the efficiency of microcapsules in the process of spraydrying were mainly researched, and the process parameters at each stage were also optimized.The indicators of microcapsule products were measured, their performance were tested, andtheir storage stability was preliminary explored.In the preparation of emulsion, we choose sucrose ester and monoglyceride as compoundemulsifier. According to the required HLB value of the formation of the oil-in-water type(0/W) emulsion and the ability of emulsifier emulsion, we could determine the radio of thesucrose ester and monoglyceride was7:3. By single factor experiment and orthogonalexperiment, we could get the optimum technological conditions for palm oil emulsionpreparation. The optimum process conditions are: emulsifier2.5%(W/W), emulsifyingtemperature70℃, high-speed shears dispersion time4min. The stability of the emulsionprepared under this process conditions with the palm oil and soybean protein andmaltodextrin was99.0%, and after the emulsion was placed in60℃water bath for8h thestratified phenomenon didn’t occur; the emulsion was stable, emulsion droplets form haduniform configuration and were well-distributed under polarizing microscope, the rheologicviscosity is moderate.The technology of spray drying microcapsule was mature and well-equipped.Instantaneous drying process does not destroy the product composition. Through theoptimization of single factor experiment and orthogonal experiment, the best spray dryingprocess conditions are: the ratio of wall material and core material was1.5:1, the radio ofcomposite wall material of soybean protein isolated (SPI) and maltodextrin (MD) was1:1, thetotal solids concentration of emulsion was25%(W/V), the homogeneous pressure ofemulsion was40MPa, the wind temperature in spray drying was180℃. Drying processsmoothly carried on and collect products were in good condition, the color of microcapsule was pure, and moisture content was low.The physical and chemical properties of the microcapsule products determination resultsshowed that the oil content of microcapsule products was38.21%, the embedding rate was82.3%; protein content was24.68%, the nutritional value was high; light density, flowproperty was good, free fall accumulation into cone gravity Angle was36.1°, the solubilitywas75.8%; according the microcapsule figure by SEM, the particle microstructure wascomplete, the shapes were the globose or ellipsoid, the surface structure was smooth; Theresults of laser particle size measurement showed that the particle size was small, more than80%of the particle size ranged between5～25μm. The TGA showed that the microcapsulehad good thermal stability, high temperature had little influence on the quality ofmicrocapsules, microcapsules had a good oxidation resistance, so the protective effect of corematerial was significant, the POV of oil increased in a small degree, delaying the rate of oiloxidative rancidity, and the embedding effect of solid fat was ideal, the oil retention rateunder preservation was high. According the FTRI analysis, there was not interrelationbetween wall materials and core materials. Finally through the GC detection, it didn’t containtrans fatty acids.