The Research Of Microencapsulated ω-3/ω-6 Fatty Acids And Its Applied To Middle-aged Formula Milk Powder

Polyunsaturated fatty acids were one of the main characteristic nutrients of middle aged and elderly people formula milk powder,including ω-3 and ω-6 PUFAs,which had multiple benefits as anti-oxidative,prevented cardiovascular disease,anti-atherosclerosis and cognition improvement.It was significant to formulate the ratio of ω-3/ω-6 to obtain functional lipids and studied their functions.This research took polyunsaturated fatty acids as raw materials,the purpose was to prepare,evaluate the properties and storage stability of microcapsules by a wet process.The main research contents and results of this paper were as follows:(1)The whey protein and maltodextrin(MD)were used as the composite wall materials,with spray drying process to prepare functional lipids microcapsules,which can improve grease stability and mask its bad odor.It was characterized by size,microencapsulation efficiency,mononuclear structure,etc.The results showed that microcapsules were milky in color and the optimum technological conditions of microencapsulation was core-wall ratio at 1:4,emulsification temperature at 50℃,homogeneous pressure at 40 MPa,air inlet temperature at 180℃,which obtained a higher microencapsulation efficiency of 95.15% and a uniform spherical shape with smooth surface.FTIR spectra of the capsule proved the presence of PUFAs in all encapsulated samples and the chemical structure of the core did not change.Moreover,it had good thermal stability at below 100℃.(2)During accelerated storage at 60℃,The microencapsulation had a slower oxidation rate,which significantly increased the oxidative stability of the core material and prolonged the storage time.The solid phase microextraction(SPME)was used to extract the volatile components from the samples and analyzed by gas chromatography-mass spectrometry(GC-MS).Combined with principal component analysis,the results show that PCA divided microcapsules of different storage periods into two sample groups according to the degree of oxidation,and 1-Octen-3-ol,(E)-2-Octenal,Hexanal,2-pentyl-Furan,2-Heptenal,2,4-Decadienal,(E,E)-2,4-Heptadienal were the main contributor flavors in infants nutrient packages.As well as the results of Colorimeter and the Electronic tongue technique are similar to SPME-GC-MS.(3)The optimum parameter condition for preparing ω-3/ω-6 fatty acid enriched middle-aged formula milk powder by wet process was: solid concentration at 50%,air inlet temperature at 180℃,feed flow rate at 1000 mL/h.Under those conditions,the middle-aged formula milk powder had a good sensory quality.Polyunsaturated fatty acids had functions and can be microencapsulated to enhance stability.Microencapsulation improved the application of PUFAs in the food field,and the results in this paper provided a theoretical basis for further broadening the development of functional products.