Study On The Extraction Of Protein From Barley Malt Roots And Its Functional Properties

Barley malt roots are the by-product of the beer industry,accounting for about 3% of the raw materials.Malt roots of a higher protein content,and also contains vitamins,minerals and other nutrients.Currently,Barley malt roots mainly used as feed.In order to take full use of the resources,barley malt roots as a raw material were systematic studied on the aspect of basic nutritional component in this paper.The optimum technology condition for preparing malt roots protein by alkali extraction and acid precipitation was studied through Single factor and orthogonal test based on protein extraction rate.Four Proteins were isolated from malt root protein by Osborne method.The relative quantity of major subunits and molecular weight distribution of the malt roots proteins were investigated by SDS-PAGE and comprehensive study on the Basic properties and functional properties.The main research conclusions are as follows:(1)The basic ingredients of malt roots were determined and the results indieated that there was higher content of protein took up 29.2% of the total weight.The contents of ash,moisture,fat and crude fiber in malt roots were 29.2%,6.9%,6.42%,1.4% and 10.7%.(2)The orthogonal test results showed that the optimum conditions are as follows,extraction pH of 9.0,material-liquid ratio of 1:25,extraction time of 60 min and temperature of 30?.The extraction rate of protein was 63.5% under the optimal conditions.The Isoelectric point of malt roots protein was pH 4.1?(3)The malt root protein purity was 72.6%.The content of fat,ash,moisture and crude fiber were respectively as follows:0.5%,6.8%,7.3%,2.1%?(4)The contents of albuminin in malt root protein were 45.79%,globulin17.46%,Prolamin 5.69% and glutelin 11.47%?(5)SDS-PAGE analysis showed that the malt root protein subunits are mainly concentrated in the 30 kDa ~ 40 kDa.There are also two electrophoretic bands,The molecular weights were 56 kDa,24kDa.(6)Through comprehensive test,The malt root protein solubility,water holding capacity,foaming capacity and foam stability,emulsifying and emulsion stability,oil absorption,and gel were diverse at different protein solubility,temperature,pH,and ionic strength.The results showed that malt root protein with good physicochemical properties and functional properties.The malt roots protein was a promising source of plant proteins.