Effect of impact-activating-disintegration treatment on grain protein fraction of autumn rye
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This paper studies the distribution of rye protein fractions according to their mass and amino acid composition while milling by machines with different work tools. The research was conducted on the autumn rye of harvest year 2017 with kernel moisture con tent of 8%. Cereals were milled in the machine of an impact - activating - disintegrating type DEZI - 15 with three - row and five - row rotors which rotate at 120 s - 1 , and in the laboratory mill with a knife - rotor work tool. The milling grain size was determined by a diffraction - type grain analyser Malvern Mastersizer 2000. The average grain size obtained from three - row disintegrating rotor was 167 μm , from the five - row rotor 158.1 μm , and from the laboratory knife - rotor mill 384 μm , respectively. The free amino aci ds composition in flour samples was investigated using the size exclusion chromatography method (SEC - method). The polypeptide composition of total grain protein has been determined by One - dimensional SDS - acrylamide gel electrophoresis. According to the ele ctropherogram results obtained from all the the content of high - protein fraction of 200 kDa . The glutelin fraction with molecular weight of 116.25 kDa is definitely observed in the sample obtained from the three - row disintegrating rotor. Whereby the lowest glutelin content has been detected in the flour sample obtained from the five - row disintegrating rotor. Fractions with molecular weight of 60 – 75 kDa – globulin fractions – come up frequently in the sample obtained from the three - row disintegrating rotor. Prolamine fractions of 45 – 47 kDa are clearly observed in the flour sample obtained from the laboratory knife - rotor mill. The albumin fraction with molecular weight of 17 – 28 kDa are mostly observed in the samples obtained by three - row and five - row disintegr ating rotors. Few LMW fractions (from 6.5 to 15 kDa ) are found in samples obtained using the impact - activating - disintegrating technique, mostly in the sample milled in the laboratory knife - rotor mill. Based on the data of free amino acid content in sample investigated it can be concluded that the impact - activating - disintegrating techniques does not cause reduction in protein biological value. The albumin rich flour milled in the disintegrator can be used for production of functional food. Due to the low con tent of glutelin protein fraction the flour obtained from the five - row disintegrating rotor offers the greatest promise for production of gluten - free foods.