Study On The Fat Mimetic Of Wheat Gluten Protein

Protein fat mimetic is one kind of fat mimetic,which is prepared by physical or chemical modifications on proteins.It can not only imitate the unique taste and flavor of fat,but also provide only half of the calories provided by the fat.It can participate in the body's normal metabolic process,to provide the body with a variety of essential amino acids,making it more nutritious and safer.In the food industry,wheat gluten protein has good functional properties,and has the characteristics of the unique flavor of grain,thus it has been widely used.Wheat gluten protein,due to its amino acid composition and interaction,has a poor hydrophobic effect,which reduces the solubility.In this thesis,wheat gluten was compound modified through deamidation and acylation.First of all by selecting the acylation level as an indicator,different gradient level of acylation were obtained through single factor experiment of reaction temperature,pH,and material ratio.And the functional properties of these proteins were measured,including emulsifying ability,emulsion stability,foaming capacity,foaming stability,water holding capacity,oil absorption capacity,and nitrogen solubility index.The optimal acylation level of WGP was calculated and selected according to a weighted average.And a comparison was carried out between the optimal sample and ovalbumin,unmodified protein,as well as single modified WGP.Secondly,the structure of the protein was characterized by Fourier infrared spectroscopy(FTIR)analysis,scanning electron microscopy(SEM)analysis,differential scanning calorimetry(DSC)analysis.Finally,the optimal modified protein was applied to the cake,replacing part of the butter.Physical and chemical analysis,texture analysis and sensory analysis of the cake were performed,to investigate whether the modified protein could be a good alternative to butter in cake.The results showed that the optimal record appeared at aeykation level 73.61%.The emulsifying ability,emulsion stability,foaming capacity,foaming stability,water holding capacity,oil absorption capacity,and nitrogen solubility index were 52.42 m2/g,17.93 min,171.43%,7.10%,6.77(g/g),3.94(g/g),26.75%,respectively.Its weighted average improved:241.49%compared to the unmodified WGP,43.14%to deamidated WGP,10.43%to succinylated WGP.The smulsifying ability of compound modified WGP was even 23.17%higher than that of ovalbumin.Wheat gluten protein mimetic(WGPFS)was a good mimetic for fat in pound cake.Cake under 20%of replacement could be accepted,and the optimal replacement ratio was 10%.The research results show that WGPFS has the potential to replace fat in pound cake.