Physicochemical Properties of Iranian Rice During Storage

Three varieties of Iranian rice were evaluated in the paddy (Tarom, Khazar, Fajr) for the cooking, textural, and pasting physicochemical properties during 18 months of storage under ordinary conditions. Testing was done for were amylose, cooking time, elongation, water uptake, and solid loss. A texture analyzer and Rapid Visco Analyzer were employed to determine hardness and pasting properties. All experiments were repeated every three months for 18 months and in three replications. Amylase was determined only for the first month. Solid loss decreased significantly over the 18 month for all varieties. The hardness of the cooked rice increased for all varieties, but was only significant for Khazar. The most significant change in the pasting properties was that the peak viscosity increased initially there was decreased. There was an initial increase in breakage followed by a decrease. In Tarom and Khazar varieties, the setback initially increased and then decreased and, in Fajr, it was initially constant and then decreased.