Enzyme-resistant starch and method for its production
A process for producing an enzyme-resistant starch uses an aqueous feed composition that comprises (i) starch that contains at least about 50% by weight amylose, (ii) water, and (iii) alcohol. The concentration of starch in the feed composition is between about 5% and about 50% by weight, and the pH of the feed composition is between about 3.5 and about 6.5. In a first heating step, the feed composition is heated to a temperature between about 130-170° C. for about 0.1-3.0 hours. The feed composition is cooled to a temperature between about 4-70° C. for about 0.1-6.0 hours. In a second heating step, the feed composition is heated to a temperature between about 110-150° C. for about 0.1-10.0 hours. The starch is separated from the majority of the water and alcohol and is dried.
1. A method of making an alpha-amylase resistant starch, comprising:
heating starch comprising at least about 65% by weight amylose in aqueous alcohol to a temperature above its gelatinization temperature, thereby destroying its native molecular structure;
maintaining the mixture at or above the gelatinization temperature for about 60-480 minutes; and
cooling the starch.
2. The method of claim 1 , further comprising separating the starch from the alcohol and treating the starch by increasing its moisture content to about 10-40% by weight and heating it at a temperature of about 90-150° C. for about 0.5-5.0 hours to impart alpha-amylase resistance.