Studyof Wheat Glutenon Protein Glycosylation

This paper used wheat gluten as protein material,fructose,glucose,maltose,dextran as glycosyl donors and under the dry condition of glycosylation to improve its functional properties.1.The effects of reaction time(d), temperature(℃) and the ratio of gluten to sugar(%)on the reaction degree, the solubility, emulsifying property and emulsifying property of the reaction products were studied.And on the preparation of which products had the best grafting degree, solubility, emulsifying and foaming process conditions wereoptimized.The results are as follows,(1)Theoptimalreaction conditions for the best glycosylation grafting degree are: To fructose, the reaction temperature is 53℃, gluten/fructose(W/W)is 110%, reaction time is2.5d(60h); To glucose,the reaction temperature is 53℃, gluten/glucose(W/W)is 205%,reaction time is 4d(96h); To maltose, the reaction temperature is 60℃, gluten/maltose(W/W)is125%, reaction time is 2.5d(60h); To dextran, The reaction temperature is 62℃, dextran/gluten(W/W)is 260%, reaction time is 13d(312h).(2)The optimal reaction conditions for the best solubility are: To fructose, the reaction temperature is 50℃, gluten/fructose(W/W)is 115%, reaction time is 1.25d(30h); To glucose,the reaction temperature is 50℃, gluten/glucose(W/W)is 190%, reaction time is 1.13d(27h);To maltose the reaction temperature is 51℃, gluten/maltose(W/W)is 270%,reaction time is1.92d(46h); To dextran the reaction temperature is 59℃, dextran/gluten(W/W)is 280%,reaction time is 12d(288h).(3)The optimal reaction conditions for the best emulsification are: To fructose, the reaction temperature is 51℃, gluten / fructose(W/W)is 140%, reaction time is 1.88d(45h); To glucose, the reaction temperature is 49℃, gluten/glucose(W/W)is 160%, reaction time is3.33d(80h); To maltose the reaction temperature is 51℃, gluten/maltose(W/W)is 290%,reaction time is 3.25d(78h); To dextran,the reaction temperature is 60℃, dextran/gluten(W/W)is 295%, reaction time is 12d(288h).(4)The optimal reaction conditions for the best foamability are: To fructose, the reaction temperature is 49℃, gluten/fructose(W/W)is 2.29d(55h), reaction time is 1.88d(45h); To glucose, The reaction temperature is 43℃, gluten/glucose(W/W)is 270%, reaction time is3.13d(75h); To maltose, the reaction temperature is 48℃, gluten/maltose(W/W)is 125%,reactiontime is 2.75d(66h); To dextran, the reaction temperature is 61℃,dextran/gluten(W/W)is 210%, reaction time is 16d(384h).2.In order to research the stability of functional properties of glycosylation products, the effects of pH and temperature on the functional properties of the grafted productswas studied.The results show that,Glycation products have a strong ability of acid, alkali and suffering fromhigh temperature.Especially near the pH of 7 which is far higher than that of natural gluten.3.In order to reveal the mechanism of improving the functional properties of the wheat gluten modified by the glycosylation reaction,the correlation between the glycosylation reaction degree and gluten index function characteristics were studied. Found that the grafting degree and solubility, emulsibility, foaming ability were significant correlation. At the same time, by using FTIRglycation products structure wasalso studied. Results showed that the two stage structure of glycosylation proteins is changed. By scanning the microscopic structure of the glycosylation surface through SEM, we can see that the molecular volume is increased a lot.