Development And Research Of Oxidation Stable New Products Of DHA Algal Oil

DHA(Docosahexaenoic acid)is an omega-3 unsaturated fatty acid that is very important to the human body.DHA cannot be synthesized in the human body and must therefore be acquired from the food.Algal oil has become a high-quality source of DHA due to its sustainability,high yield and low environmental impact.However,DHA algal oil is highly susceptible to environmental influences and oxidizes,leading to the loss of nutrients,which limits its application in the food field.In this study,the emulsion is selected as the carrier system to embed DHA algal oil,and the effect of different concentration of sweet orange essential oil(SOEO)on the oxidation stability of algal oil emulsion and the change of the interface environment are explored,and the problem of oxidation stability is solved by the synergistic effect of SOEO and antioxidants.Based on this,two new DHA algal oil products-DHA algae oil oral liquid and DHA algae oil solid granules were developed,and their physical and chemical properties and storage stability were investigated.The main findings are as follows:Using the emulsion as the carrier system,sodium caseinate(Na CS)as the emulsifier,and natural orange essential oil(SOEO)as the antioxidant,the effect of the concentration of the essential oil on the physicochemical properties of the algal oil emulsion was investigated.The influence of SOEO concentration on the interface environment of protein-stabilized algal oil emulsion and the influence of essential oilprotein interactions on the oxidation stability of emulsified algal oil(O/W)were explored.The results shown that adding different concentrations of SOEO had no effect on the microstructure and physical stability of the algal oil emulsion.The addition of SOEO improved the oxidation stability of the algal oil emulsion and the adsorption of interfacial protein.The lipid oxidation values of algal oil emulsions with 0 and 10%SOEO were 198 and 100 mmol/kg algal oil after 16 days of accelerated oxidation,respectively.The absorbed protein level was higher in the algal oil emulsion containing10% SOEO(70%)than in 0% SOEO(57%).The interfacial protein load and oxidation stability increased and then decreased as the SOEO concentration in the oil phase of the emulsions was raised,with maximum values being observed around 10% SOEO.The above results indicate that the presence of SOEO enhanced the interfacial thickness,possibly by interacting with the casein molecules.A thicker protein layer may have helped to retard the oxidation of the omega-3 oils inside lipid droplets.Emulsion was selected as the carrier of DHA algal oil,the emulsifiers and antioxidants were selected to develop algal oil oral liquid.The free fatty acid release rate(FFA release rate),bioacceptability and storage stability of algal oil oral liquid were investigated at room temperature for 6 months.The results show that the preparation method of a stable algae oil oral liquid product is as follows: Na CS is used as emulsifier;oil content is 10%;EDTA,TBHQ and orange essential oil are compounded as antioxidants;bus sterilization is used as a sterilization method;vacuum emulsification is selected the reaction kettle is a way of emulsification and homogenization.In addition,the FFA release rate and bioacceptability rate of algal oil oral liquid was 78.79%and 90.57%,respectively.Algal oil oral liquid had good physical stability,oxidation stability and high retention rate of DHA(97.0%)when stored at room temperature for6 months.Based on the above experiments,it can be seen that the samples still have good stability after being stored for 6 months under normal temperature conditions.Based on the development of the formulation of DHA algal oil oral liquid,the DHA algae oil solid granules is prepared by spray drying method for microencapsulation.The core-to-wall ratio is 1:1.5,and the solid content is 50%.The algal oil solid powder has good solubility(96.22%),rehydration and oxidation stability;surface oil content(0.78%)is compliant with the industry standard SC-T 3505-2006(?1%);and it has a high embedding rate(98.20%).The appearance of the products is spherical,the surface of the oil droplets is smooth and tight,and there is no leakage and dryness.The recovery emulsion has good performance,uniform color,no precipitation and impurities,and no fat film on the liquid surface.Based on the above experimental results,the results shown that the embedding of DHA algae oil solid granules product was relatively successful and has good stability.