Study On The Effects Of Heat Moisture Treatment On Germinated Wheat And Starch Composition

In this paper,with Zhengmai 366 as raw material,based on the physicochemical properties of wheat flour and wheat kernel which germinated in different degree,the germinated wheat kernel and its flour were HMT at different conditions(moisture,temperature,time of different levels).The effects of two methods on physicochemical property,falling number,content of damage starch,solubility,swelling power,pasting property,thermal property,structure property(surface of starch granule,crystalline texture)were analyzed and discussed.The optimum condition of HMT was acquired.The wheat starch was treated by HMT and its physicochemical property,structure property were studied.Wheat flour and starch treated by above three methods were added to primary wheat flour.The feasibility research was studied by application on noodle.Main conclusions of study are as follows:After germination,increasing of seed internal activity resulted in a hydrolysis of large molecular carbohydrate and protein,increase of damage starch content,but the crude protein content unchanged;Decrease of protein quality resulted in poor gluten and development time and stability time decreased.It was found that the hydrolysis of starch led to the deterioration of flour pasting properties and the peak viscosity,peak viscosity,gelatinization temperature and peak time were decreased.Wheat kernel was treated by HMT.After milling,the physicochemical of germinated wheat flour was studied.The results showed that compared with control,appropriate treatment could improve quality of wheat.The optimal condition: moisture content 25%,temperature 100℃,time 60 min.But very few parameters,such as peak viscosity,gelatinization temperature and falling value,were still lower than those of the original wheat,and HMT could improve the properties of wheat starch.Wheat flour germinating was treated by HMT and the physicochemical of germinant wheat flour was studied.The results showed that HMT could effectively passivate inactivated wheat amylase,reduce the damaged starch content in germinated wheat powder,significantlyimprove the gelatinization properties of germinated wheat flour,prompting disintegration of the double helix and increase of starch crystalline region,amorphous region arranged more orderly,but also the formation of more crystalline structure,and make the original crystal structure tends to be perfect,the optimum processing conditions :moisture content 25%,temperature 100 ℃,time 60 min.But the heat treatment will lead to flour whiteness and color variation,protein denaturation.Wheat starch germinating was treated by HMT and the physicochemical of germinated wheat flour was studied.The content of damage starch,solubility and swelling potential,pasting properties,structure analysis(particle surface morphology,crystalline structure),thermal properties and FTIR were analyzed.The HMT has great modification effect on high damage starch(high degree of germination of wheat flour isolated starch).HMT may be increase the thermal motion of the starch molecules,The hydration of starch molecular hydrogen bond was significantly enhanced and modified by heat treatment is greater than the damage of thermal damage.Solubility and swelling power had significant increase.Pasting parameter of wheat starch rose.The optical conditions were 25%,temperature 100 ℃,time 60 min.Under these conditions,the maximum crystalline degree reached 19.64%.The diffraction peak intensity increased significant.After treatment with HMT,the surface of starch granules was not smooth,and the starch molecules were broken during the process of heat treatment.The infrared spectrum analysis showed that the heat and moisture treatment promoted the association of hydrogen and oxygen bonds in the damaged starch granules,which may lead to the formation of a new crystalline region,which makes the free chemical bond bind with each other.The DSC parameters were significantly improved after HMT,and the thermodynamic properties and thermal stability were improved significantly.The feasibility research was studied by application on noodle.Different levels of sample were added to commercial wheat flour.Results showed that luster of noodle added wheat starch was the best,noodle added wheat flour which was treated by HMT took second place,noodle added germinated wheat flour was the worst.Texture analysis show that quality of noodle added wheat starch by HMT is the highest.The sensory evaluation of heat treatmentwheat starch noodle was higher than two other wheat f lour noodle.The rate of cooing loses:wheat kernel by HMT>wheat flour by HMT>wheat starch by HMT.There was no difference compared with T0.