Structure And Characterization Of Structured Camellia Oil System Stabilized By Tea Pholyphenol Ester Particles

In this paper,tea polyphenols palmitate(Tp-palmitate)nanoparticles were obtained by thermal dissolution-rapid freezing.The Picerking emulsion was prepared by using this particle as stabilizer.The effects of the volume ratio of oil to water phase and the concentration of Tp-palmitate particles on the emulsion type,particle size,microstructure and rheological properties were investigated.A stable oleogel system was constructed by using emulsion template method combined with Tp-palmitate and citrus pectin.The effects of volume ratio of oil to water and pectin concentration on the properties of emulsion templates,dried samples and oleogel products were explored.The oxidation stability of oleogel products was characterized by DPPH clearance rate,acid value,peroxide value and accelerated oxidation test.The application of oleogels in cake was preliminarily studied.The microstructure,rheology and texture of cake batter and product were investigated and analyzed.The specific conclusions are as follows:(1)Construction and characterization of Tp-palmitate particle-stabilized Pickering emulsified camel ia oil system.The ?w of Tp-palmitate is greater than 130° and the Tppalmitate particles of about 300 nm can be formed in camel ia oil by t thermal dissolution-rapid freezing.The W/O Pickering emulsion was prepared by using this particle as stabilizer.The effects of the volume ratio of oil to water and the concentratio n of Tp-palmitate particles on the properties of the emulsions were investigated.The results show that when the oil-water ratio is greater than 7:3,the emulsion has fine appearance,uniform particle size and high stability.With the increase of Tp-palmita te concentration,the droplet size decreases,the stability increases and the gel properties increase.When the oil water ratio is 8:2 and the Tp-palmitate particle concentration is 2.5%(m/v),the emulsion obtained is semi-solid paste,and has good stability and gel properties.(2)Construction and characterization of oleogel stabilized by Tp-palmitate and pectin compound.The emulsion-template method was used to establish the olegel system based on camel ia oil.The effects of volume ratio of oil to water and pectin concentration on the properties of emulsion templates,dried samples and oleogels were investigated.The results showed that the viscosity and elastic modulus of emuls io n template increased with the increase of oil volume and pectin concentration.The hardness of dried samples increased with the increase of Pectin concentration,and decreased with the increase of oil content.The oleogel exhibited strong oil holding capacity,good temperature stability,certain structural recovery and strong gel properties,and the gel strength increased with the increase of Pectin concentration.The gel concentration decreased with the increase of oil phase content.When the ratio of oil to water is 6:4,the concentration of Tp-palmitate is 2.5%,and pectin concentration is 3.5%,a better quality product can be obtained.(3)The study on the oxidative stability of oleogels stabilized by Tp-palmitate and pectin composite showed that the DPPH removal rate of the gel could reach 125.28% of the commercial camel ia oil.The growth rate and total amount of peroxide value,panisamine value,total oxidation value and carbonyl value during the heating process were lower than that of the camel ia oil under the same condition,showing good oxidation stability.(4)Preliminary study on the application of oleogels stabilized by Tp-palmitate and pectin in cake shows that compared to butter,the cake batter with oleogels has a slightly larger mechanical strength and lower gas holding capacity,and the internal structure of the cake product is slightly firm and slightly rigid.