| 摘要 |
PURPOSE:To obtain the subject peptide having low color-developing deterioration tendency and utilizable in the field to require color deterioration resistance, e.g. protein-enriched drink and cosmetic base, by washing a vegetable protein near the isoelectric point and hydrolyzing the protein with an endoprotease. CONSTITUTION:Separated soybean protein is dissolved in water, pH of the solution is lowered to 4.5, the precipitate is separated by centrifugal separation to remove the soluble fraction, water is added to the residual insoluble fraction, the pH of the suspension is adjusted to isoelectric point or thereabout with 20% sodium hydroxide solution and the vegetable protein is washed. A proteinase containing endoprotease is added to the washed vegetable protein, incubated at 50 deg.C for 5hr and centrifuged to remove the insoluble substances. The obtained supernatant is heated at 80-85 deg.C for 20min to effect the inactivation of the enzyme and the sterilization of the liquid. The product is freeze-dried to obtain the objective vegetable protein peptide containing <=1% free sugar and <=2% free amino acid and having low color-developing deterioration tendency. |
