Research On Properties Of High-Moisture Textured Soy Protein

China is the hometown of the soybean, also is the great nation of soybean food producing and expending. The soybean protein has the very high nutritional value, the compositions of the amino acid balance basically except the methionine and the cystine to be slightly lower than than the recommended value of FAO(the United Nations Food and Agriculture Organization), are complete proteins. The Tenth Five-Year Plan of China National Food Industry explicitly pointed out that:"Emphatically develops the newly emerging soybean food which has broad market or big potential market, such as soybean milk, soybean milk powder, soybean isolate protein, soybean concentrate protein, textured soybean protein and so on."Defatted soy flour was extruded in a twin-screw laboratory DSE-25 scale extruder. The effects of process parameters include feed moisture content(FMC), barrel temperature(BT), feed speed(FS) and screw speed(SS) on physico-chemical properties, texture properties of extruded products were studied. Based on single-factor experiment, binary quadric orthogoral regression rotational combination experiment was used to optimize process parameters. We obtained the optimum product from the optimum process parameters. The optimum product was used to analyze its drying, re-hydrating, cooking, freeze-defrosting, frying, flavour and pigment absorbing, storaging properties. etc. The result indicated that:1 A continuous increase in FMC increased L value, content of available lysine(A-lys) and texture index(TI); but decreased chewness, shear force(SF), pressure and torque; oil absorbtion capacity(OAC) increased when FMC raised from 35% to 45%, but decreased when FMC raised from 45% to 50%; there was a little change of water-holding capacity(WHC) and nitrogen solubility index(NSI).A continuous increase in BT(zone 3) increased OAC, NSI and TI; but decreased A-lys, pressure and torque; L value appeared to decreased when BT was changed from 120℃to 130℃, but decreased from 130℃to 160℃; WHC and chewness decreased when BT was increased from 120℃to 140℃, but increased when BT was increased from 140℃to 160℃;...