| Public health problems caused by high-fat foods have become a hot spot in the society.Research on fat substitution has become a hot direction in the field of food science.Soy protein isolate(SPI)and egg white protein(EWP)are the representative vegetable protein and animal protein.The protein compound of SPI and EWP was investigated in this paper.The optimum proportion of SPI and EWP was determined by texture profile analysis(TPA),rheology analysis and chroma analysis.The micronization technique are used to obtain desired particle size under 10 μm,which will provide the expected fat mimicking organoleptic properties.The main results of this paper are as follows:1.The gel formation temperature of the protein compound of SPI and EWP and the effect of p H value on the gel formation temperature were determined by Differential Scanning Calorimetry(DSC).The result showed that the proper gel formation temperature was 95℃ and with the increase of p H value,gel formation temperature of the system increased.The tests of solubility and gelling properties indicated that 10% to20% protein concentration was needed in gel formation.There were significant differences in texture properties(P<0.05)between the three gel samples.When the protein concentration was 10%,the samples were consistent with the requirements in hardness,guminess and chewiness,and needed the least energy consumption.Above all single factor experiments,the conditions for the gel formation were determined as follows: the temperature was 95℃,the protein concentration was 10%,the p H value was7.Five samples with different proportion of SPI and EWP(SPI:EWP were 1:3,1:2,1:1,2:1,3:1 respectively)were detected by TPA,rheology analysis,water-keeping ability,chroma analysis and scanning electron microscope(SEM).The particle size and rheological properties of the fat analogue after micronization were also determined.The optimal protein compound proportion was 1:1(w/w)and it had high water-keeping ability and proper texture and rheological properties,the dense gel network was formed under scanning electron microscope(SEM).The micronization condition were speed10000 r/min and time 3 min respectively,the average size of protein particles was about4.53 μm.Finally,the fat analogue was prepared by freeze-drying.2.Compared to full-fat sample and low-fat sample,three addition amount of fat analogue were applied in dumpling and the mimicking effects were evaluated by sense evaluation analysis,TPA and chroma analysis.The best ratio of the fat analogue in dumpling were 5%.In sensory evaluation,5% protein compound gained the highest scores among three fat analogue samples.The scores of three fat analogue samples were higher than low-fat sample,closed to full-fat sample.The differences among three analogue samples in yield,density and p H value were not significant(P<0.05).Three addition amount(5%,7.5% and 15%)were all accepted in dumpling.3.Full-fat sample,low-fat sample and three addition amount of analogue samples applied in pork cake are compared,the results showed that adding 15% analogue sample had the best sensory effect,even as good as the full-fat sample.The differences among three fat analogue samples in yield and p H value were not significant.Three addition amount of the fat analogue(10%,15% and 20%)were all accepted in pork cake. |
PDF Full Text Request