A method for determining degree of gelatinisation of rice starch or rice flour, based on the amyloseliodine blue value after dispersion in alkali, has been deueloped. The method can be used to follow the course of cooking of rice under different conditions, and has been checked against a novel infrared technique for relating degree of gelatinisation to the phenomenon of hydrogen bonding.(Zusammenfassung siehe Seite 100; RksumC 2 la page 100)

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The extent of gelatinisation achieved by heating rice at various moisture contents was determined by an X‐Ray diffraction technique and a method involving the differential alkali solubility of amylose in raw and gelatinised starch. The results obtained by these methods agreed closely (γ = 0.980) confirming that the alkali solubilisation technique gave a measure of starch crystallinity. Above 20% moisture content the extent of gelatinization was governed by the amount of water present. Gelatinisation was not completed unless the moisture content exceeded 40%, which corresponds to the typical moisture level of rice which has been soaked and steamed as in the parboiling process.

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