Preparation And Properties Of Antarctic Krill Oil Microcapsules

The Antarctic krill oil has high nutritional value and good health care function,has great development potential and broad market prospects,but it is rich in unsaturated fatty acids,easy oxidation effect of Antarctic krill oil quality,its application has been limited.The Antarctic krill oil products in order to form a single,comprehensive development and utilization of Antarctic krill oil,rich in the form of its products,the microencapsulation.Select the appropriate package wall live krill oil can be from viscous oily material into powder with good fluidity,small particles formed 5~200?m,which can protect the Antarctic krill oil is not oxidized,or masking shrimp flavor,and convenient transportation and storage,and broaden the application of Antarctic krill the field,rich product form.This study was prepared by spray drying of Antarctic krill oil microcapsule,and its properties were studied,the optimized process is simple and feasible,low cost,suitable for large-scale industrial production,this study can provide a theoretical reference for the industrialized production process.Research objective1.Preparation of Antarctic krill oil microcapsules by spray drying was studied.2.The basic properties of the microcapsules of Antarctic krill oil was studied.3.The release kinetics and oxidative stability of Antarctic krill oil microcapsules were elucidated.Research contents1.This study selected glycerol monostearate and sucrose fatty acid ester as emulsifier,modified starch,soy protein isolate,Arabia gum and maltodextrin as wall material,the emulsion stability as the evaluation index,using single factor experiment to determine the emulsifier and wall material with the quantity and proportion,then orthogonal experiment optimization the ratio of wall material.To determine the suitable wall material ratio,process equipment of Antarctic krill oil microcapsule embedding rate effect,the response of inlet air temperature,feed rate,homogenization pressure parameter optimization experiment.2.The properties of the Antarctic krill oil microcapsules prepared using the best process were investigated,including physicochemical properties,thermogravimetric analysis,scanning electron microscopy,particle size distribution,and lipid composition and fatty acid composition of Antarctic krill oil before and after spray drying.3.The storage experiment of Antarctic krill oil microcapsules was carried out,and the retention rate of the Antarctic krill oil microcapsule core material was used as evaluation index to study the release kinetics of the microcapsule core material under different temperatures and humidity conditions;the embedding rate was an evaluation index,and the influence of different packaging conditions on the microencapsulation efficiency was studied.Using the peroxide value as an evaluation index,the oxidation kinetics of the microcapsules was studied and the shelf life was predicted.Research conclusion1.Orthogonal test was used to optimize the preparation process of Antarctic krill microcapsule emulsion.The best formula was:emulsifier 1%,acacia 10%,modified starch 15%,soybean protein isolates 15%and maltodextrin dosage 60%,it is verified that emulsion stability reaches 91.22%under this condition.The response surface methodology was used to optimize the spray drying preparation process.The best preparation process was:homogeneous pressure 34Mpa,inlet air temperature 165°C,and feed volume 12.5m L/min.Under these conditions,the microcapsule loading was verified to be 25%,the best embedding rate reached 82.26%.2.The basic physicochemical indexes of the Antarctic krill oil microcapsules are as follows:water content 1.89±0.28%,ash content 2.04±0.34%,bulk density 0.35±0.37mL/min,and angle of repose 38.50±0.42o.The hygroscopicity of microcapsules first increases with time and then tends to be stable at a later stage.The product's particle size is concentrated in 15~30?m,and it is in a normal distribution.The shape particles are rounder and nearly spherical,and the surface is smooth,dense and crack-free.The content of polyunsaturated fatty acids such as astaxanthin,EPA and DHA in Antarctic krill oil slightly decreased after microencapsulation,but overall,there was no significant change in lipid composition and fatty acid composition,indicating that the entire process did not destroy Antarctic krill oil functional ingredients demonstrate the feasibility of the process.3.Under different temperature and humidity conditions,the retention rate of Antarctic krill oil microcapsule core material decreased significantly with the increase of temperature and humidity.Avrami's formula is used to fit the release kinetics of the microcapsule core material.The fitting R~2 is greater than 0.98.Therefore,this formula can be used to explain the release rule of the microcapsule core material under different temperatures and humidity conditions.In the storage stability experiment,the embedding rate of the microcapsules gradually decreases with the prolongation of the storage time,and the vacuum packing can delay the decreasing rate of the embedding rate.The peroxide value of Antarctic krill oil and microencapsulated products increased with storage time;the increase of peroxide value after vacuum packaging treatment slowed down;the increase of peroxide value after microencapsulation decreased significantly;microcapsules the vacuum packaging treatment after the treatment can effectively increase the oxidative stability of the krill oil and can effectively prolong the storage time of the microcapsules.The oxidation kinetics of krill oil and microencapsulated products were fitted.The results showed that the first-order kinetic equation R~2 was greater than 0.98.Combined with the empirical formulas of Arrhenius and Vant'Hoff,the shelf life of krill oil and microcapsule products was studied.The results show that the storage time of the microencapsulated krill oil can be prolonged from 180 days to 336 days at room temperature,and the shelf life can reach 412 days after vacuum packaging.This study selected four types of wall materials and used spray drying technology to microencapsulate Antarctic krill oil,which can effectively improve its storage stability,facilitate processing,transportation and storage,and also improve product safety,fluidity,and water solubility.The scope of application of Antarctic krill oil has been expanded to provide a certain reference for deep processing of Antarctic krill oil and development of the industry.