| Defatted flax cake meal is often used as a low-value protein supplement in animal feed or fertilizer.It contains 35 to 40%crude protein and is a very high-quality protein resource.Linen cake meal has a high phenolic content of flaxseed residues.Linen cake meal in the flaxseed shell part also exists in high viscosity and is rich in flaxseed gum.Therefore,in this study,flaxseed meal was used as the raw material for the extraction of experimental materials,and the extracted protein and polyphenols were covalently conjugated using the alkali method to make complexes and to verify their characterization and functional properties,and the protein and polyphenol complexes and different ratios of flaxseed gum were used to prepare emulsions loaded with lycopene,and finally the decomposition rate,lipid oxidation and bioavailability of lycopene in the emulsions were measured.The findings were as follows:(1)The purity of flax protein prepared by alkali solubilization and acid precipitation method was 86.6%,the crude fiber content was 3.74%second only to the protein content,and the phenolic content of protein and flaxseed polyphenol complex(FPI-FPP)after alkali conjugation was 92.56 mgGAE/g;the amino acid content of FPI-FPP was reduced in the experimental group compared with the blank content;Fourier transforms infrared spectra The results showed that the maximum absorption wavelengths of FPI-FPP amide A,amide Ⅰ and amide Ⅱ bands were red-shifted or blue-shifted;polyacrylamide gel electrophoresis showed bands at 70 kDa and the top of the lane of FPI-FPP that were not present in FPI.the clearance of DPPH and ABTS of FPI-FPP was significantly higher than that of FPI(P<0.05),with 10 mg/mL concentrations of 95.68%and 95.68%,respectively.The results showed that the FPI-FPP complex was successfully produced and its antioxidant properties were significantly improved.(2)Scanning electron microscopy results showed that FPI-FPP exhibited a flatter and more uniform surface relatively flat but porous on the surface;non-covalent interactions had a slight effect on the solubility of FPI,and the shift of the isoelectric point may explain the increase in solubility,and the average particle size of FPI-FPP as a percentage of volume was 830.07 nm.The particle size of the complex FPI-HT was the largest and most dispersed.The surface contact angle of FPI-FPP was 55.5°,and the experimental results indicated that the emulsification activity and stability of the protein complex emulsions were enhanced.(3)The emulsion index,droplet size and ζ-potential of emulsions with different oil phase fractions were analyzed,and the emulsion index decreased significantly(P<0.05)from 82.17%to 22.63%as the oil phase fraction increased from 10%to 30%.The droplet size distribution of the miscible emulsions had the lowest particle size of 10.23 μm at 0.5%FG concentration,and the potential of FPI-FPP miscible emulsions with different concentrations of FG was-24.5 mV without the addition of FG and 27.3 mV with 0.5%FG.The droplet sizes of all emulsions were significantly higher at 90℃ heat treatment and at 60 The droplet size of the emulsions with 0.3%and 0.5%FG was not significantly different compared to 30℃,with droplet sizes of 13.27 μm and 10.97 μm,respectively.The experimental results showed that the addition of FG could effectively improve the physicochemical stability of the emulsions.(4)The emulsions were bright yellow in the 10%low oil phase fraction emulsion system,and the difference in Δb*values exhibited by the FPI-FPP complex emulsions from 11.59 at day 0 to 11.15 on day 14 was not significant,and the brightness of FPI emulsions and FPI-FPP emulsions decreased with storage time.the FPI-FPP emulsions were more efficient in protecting LP than FPI emulsions,and the retention of LP after 18 d after storage,the retention rate of LP was 87.61%significantly higher than that of FPI(P<0.05).The release of free fatty acids from FPI and FPI-FPP after 120 min of enteral digestion was 71.2%and 72.5%,respectively,and the bioavailability of FPI-FPP emulsion was 46.52%,which was significantly higher than that of FPI emulsion at 26.8%.The experimental results showed that the emulsions prepared by FPI-FPP and FG could effectively improve the storage stability and bioavailability of LP. |
