Method for inhibiting the deterioration of eating-quality characteristics of foods containing gelatinized starch
An object of the present invention is to provide a method for inhibiting the deterioration of eating-quality characteristics of a food containing gelatinized starch and to keep their eating-quality characteristics as just prepared after a relatively prolonged storage under freezing, refrigerating, chilling or room temperature. The present invention achieves the above object by a method of permeating of maltose and/or α,α-trehalose or saccharides comprising the same and other oligosaccharides in a prescribed ratio into the above food containing gelatinized starch by admixing the saccharide to the food and holding them at relatively high temperature for a prescribed period.
1. A method for producing a cooked rice, comprising the steps of:
(a) boiling a raw rice,
(b) keeping the resulting boiled rice to 70 to 90° C., and
(c) adding a solution of a saccharide mixture comprising (i) maltose, (ii) α,α-trehalose, and (iii) one or more saccharides selected from the group consisting of maltotetraose containing maltooligosaccharides and α-maltosyl α,α-trehalose, said mixture being in an amount of 5 to 15% (w/w) of the weight of said raw rice, on a dry solid basis, to said boiled rice, said solution having been heated at a temperature of 70 to 90° C.,
so that said saccharide mixture permeates into said boiled rice,
said saccharide mixture comprising maltose and α,α-trehalose at a total content of 30 to 70% (w/w), on a dry solid basis, and the weight ratio of said maltose to said α,α-trehalose is 7:3 to 2:3,
whereby a cooked rice, in which the retrogradation and hardening of the resulting gelatinized starch are inhibited without increasing sweetness, is produced.
2. A cooked rice prepared by the method of claim 1 .
3. The method of claim 1 , which further comprises, after the step (c), a step of keeping said boiled rice added with said saccharide mixture at a temperature of 70 to 90° C. for 25 minutes or more.
4. The method of claim 1 wherein at least one maltotetraose-containing oligosaccharide is a maltotetraose-rich oligosaccharide.
5. The method of claim 1 wherein (iii) comprises a maltotetraose-rich syrup.