Soy spent flakes

Figure 3. Elastic and loss moduli of four soy products. SSF = Soy Spent Flakes, DSF = Defatted Soy Flour, SPC = Soy Protein Concentrate, SPl = Soy Protein Isolate. Arrows indicate the regions of glass transition. Measured at 0.05% strain and 0.16 Hz. (Reproduced from reference 17.)...

One part of commercial defatted soy flakes was extracted with ten parts of dilute NaOH (pH 9-10). After removal of spent flakes, the total extract was adjusted to pH 4.5 with dilute HCl to precipitate the curd. The curd was washed three times with H2O, resuspended at pH 7.0, and freeze dried. Intrinsic viscosity, optical rotation, and differential scanning calorimetry (DSC) measurements show the soluble fraction of curd to be native. 

Shen (1994a,b) treated protein extract slurry with P-glucosidase, pH 6-8, to produce aglycones, then separated the soluble protein extract with the insoluble spent flakes, which was an aglycone-enriched soy fiber. The dried fiber fraction contained 1-2 mg genistein/g and 0.7-1.7 mg soy hber/g. 

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