| 摘要 |
PROBLEM TO BE SOLVED: To prevent the breakage of flock in a filtration stage and remove the subject protein in extremely high efficiency by adding a positively charged silica sol to a liquid containing a protein. SOLUTION: A silica sol having positive electric charge is added to a protein- containing liquid such as Sake (refined Japanese rice wine), Mirin (sweet Sake used as a seasoning), wine, beer, food vinegar, soy sauce and fruit juice. The positively charged silica sol may be added in combination with a negatively charged silica sol. The positively charged silica sol is a colloidal silica sol having positive electric charge on the surface of the particles. The particle surface of colloidal silica has negative charge because the colloidal silica is an acidic oxide, however, a positive charge can be applied to the negatively charged colloidal silica by coating the surface of the particle, e.g. with fine metal oxide particles having positive charge (preferably alumina). |
