| 摘要 |
A process for purifying amylose comprises forming a solution of impure amylose in water, treating the solution with a water-insoluble, amylose-inert, sorbent filter aid, separating the filter acid from the solution, and recovering the amylose from the separated solution. The amylose may be amylose resulting from the fractionation of starch, whole starch composed of at least 50% amylose derived from e.g. highamylose corn, degraded amylose produced by hydrolyses or hydrolytic oxidation or amylose derivatives e.g. hydroxyethyl amylose. Specified filter aids are diatomaceous earths, fibrous asbestos, fibrous wood cellulose, activated carbon, and clays. The amylose solution may be formed by heating amylose and water to 150 DEG F. or above, e.g. 250 DEG F.-350 DEG F. for 1-30 minutes, suitably by mixing an amylose-water mixture with high-pressure steam, or by using an autoclave or a coiled heat-exchanger. The solution may be made in presence of the filter and e.g. 1-15% by weight based on the amylose, the filter aid then being separated by filtration or centrifugation, or the solution may be passed through a bed of filter-aid. The purified amylose may be recovered by spray- or roll-drying, or by precipitation with an organic water-miscible liquid. |
