| As a processing method,germination treatment can significantly increase the content of active substances,nutrients as well as processing properties in the miscellaneous grains,it can also produce a unique flavor and taste.Currently,germination cereal and bean are used as fresh food and beer production,which is a single form and the waste of resources.Therefore,on the basis of systematic research on mung bean and highland barley starch,protein and its quality,it is necessary to increase production and application and develop new products.In this paper,germinated mung bean and highland barley were used as raw materials,the mung bean was germinated at 25 ~oC for 12,24,36,48,60 and 72 h;the highland barley was germinated at 25~oC for 12,24 and 36 h,and dried by a blast drying(AB)and an infrared drying(ID)method(the moisture content of the dried highland barley was 10%±1 as the end point),respectively.We studied the basic composition,microstructure and quality characteristics of mung bean and highland barley after germination,the microstructural and physicochemical properties of their starch and the microstructure and function properties of their protein.Additionally,the microstructure,cooking characteristics and texture characteristics of noodles after adding germinated grain flour were studied as well.The main conclusions are as follows:(1)With the increase of germination time,the content of starch,amylose,ash and crude fat in mung bean gradually decreased,while the protein content increased,the total antioxidant capacity first increased and then decreased.The b~*,?E,the water absorption index,oil binding ability and water retention capacity gradually increased;the brightness,the a~*,peak viscosity,breakdown,final viscosity,setback,peak time and peak temperature gradually decreased,while the water solubility index showed no significant change before and after germination.After germinating,most of the mung bean had dents on the surfaces with fragments.The small molecular weight of the sprouted mung bean starch had a lower tailing time than the native,which meant the small molecular starch of mung bean was first hydrolyzed after germinating.The crystallinity,transparency,T_o,T_p,T_c and?T of the germinated mung bean starch were higher than the native.With the prolongation of germination time,the pasting characteristics and enthalpy values of mung bean starch gradually decreased,and the setback value gradually increased.The change in the structure of the mung bean protein after germination for 72 h affected the functional properties,the emulsification,foaming,water absorption and oil absorption of the mung bean protein were enhanced after germination,and the emulsion stability became lower.The molecular weight and crystal form of the mung bean protein before and after germination did not change significantly.(2)The content of tannin and amylose and the value of L~*from highland barely did not change significantly after germination.As the germination time prolonged,the protein content,the value of b~*and?E,total antioxidant capacity,bulk density,water solubility index and water retention capacity increased gradually,while the content of starch,ash and crude fat,a~*value,pasting properties,water absorption index and oil absorption capacity decreased gradually.After germination,most of the highland barley starch granules had dents and holes on the surface.It has been found that germination reduced the molecular weight,crystallinity,swelling power and transparency of highland barley starch,while significantly increased water holding capacity,solubility and thermal properties.With the increase of germination time,the initial temperature,denaturation temperature and final temperature of the highland barely protein gradually decreased.The content of?-sheet,?-helix,random curl and?-turn had no significant different between the native and the germination.The content of?-sheet and random curl increased first and then decreased with the increase of germination time.The crystal form and molecular weight of the highland barely protein did not change obviously before and after germination,and the diffraction angle still showed positions of 9°and 20°.The drying method significantly affects the quality of germinated green barley powder,starch and protein.(3)Adding 10%,20%and 30%germinated mung bean powder to the wheat flour,respectively,the color of the noodles was deeper and the color was biased towards green and blue compared with the noodles without adding germinated mung bean powder.After adding germinated mung bean power,the cooking time,cooking loss rate and water absorption rate of the noodles prolonged,increased and decreased,respectively.The qualitative characteristics of raw noodles and cooked noodles decreased with the increase of the amount of germinated mung bean powder added.The texture parameter value of raw noodles was mostly higher than that of cooked noodles,and the cohesive force was less than that of cooked noodles.The noodles prepared by mixing 10%,20%and 30%germinated barely powder in wheat flour,and as the amount of addition increased,the brightness of the noodles became lower,and the color was biased toward green and blue.At the same time,due to the addition of the sprouted highland barely powder,the best cooking time shortened,the cooking loss rate increased,and the water absorption rate decreased.The hardness,cohesiveness,elasticity,firmness and resistance to stretch of raw noodles were generally higher than those of cooked noodles.Germination treatment had different effects on starch,protein and its quality including structural,physicochemical and functional properties,but it did not change the crystal form of starch.Drying method also affected the physical and chemical properties and functional properties of cereals.Making noodles can improve the nutritional value of noodles,but it would reduce the quality of noodles.The research will provide a basis for improving the quality of the network structure of noodles. |
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