Physical Properties and Eating Qualities of Newly Developed Waxy Rice

Abstract

Cooking and processing properties of four kinds of newly developed waxy rice, Oumochi 349, Odorokimochi, Kantomochi 171 and Komochi 360 were studied. Samples were tested for their physical properties and eating qualities as flour, rice cakes and steamed rice. To investigate the influenceof one-year storage on cooking properties, waxy rice samples harvested in 1994 and 1995 were compared. The pasting properties of flour were determined with a Rapid Visco Analyser (RVA) and the textural properties of gel with a Tensipresser. Rice cakes were prepared in a rice cooker, and the textural change with storage time was studied. Sensory evaluation of rice cakes and steamed rice was done by a scoring method. RVA curves differed among the samples. Pasting viscosity of Odorokimochi was as high as that of Himenomochi, and that of Mochiminori was as low as that of Hiyokumochi. Firmness and stickiness of the gel showed a positive relationship with viscosity. As a rice cake, Odorokimochi was highest in firmness, followed by Himenomochi, and the firmness increased drastically with time. The rice sample harvested in 1994 was higher in pasting viscosity as flour and firmness as rice cake than that form 1995. Hence, there was a one-year storage influence on the cooking properties of waxy rice. Sensory evaluation of rice cake and steamed rice showed the same tendency. Hiyokumochi was preferred in all profiles and the sensory score for Odorokimochi was between those for Hiyokumochi and Oumochi 349.