GELATINIZATION BEHAVIOR OF GRAINS AND FLOUR IN RELATION TO PHYSICO-CHEMICAL PROPERTIES OF MILLED RICE (ORYZA SATIVA L.)

ABSTRACT

Physico‐chemical properties of milled rice grains of 13 japonica varieties were evaluated. The rice varieties differed in appearance. One sample had long grains (6.61 mm), two had short grains (5.27–5.32 mm) and the rest had grains of medium length (5.52–6.55 mm). The shape (length/width) of grains varied from bold (1.58–1.9) to medium (2.06–2.37). The protein content was high in all samples (7.82 to 9.72% on dry mass). Almost all, with exception of one cultivar (Osogovka), which had intermediate amylose content (23.3%), were low amylose varieties (12–19.4% amylose). Their minimum cooking time varied from 17.5 to 22.5 min. Significant correlations (P < 0.05) were established between some physico‐chemical characteristics of evaluated rice cultivars. Elongation during minimum cooking time was correlated with protein content (r = 0.6899), shape (?0.7137), thickness (0.7234) and width (0.9134) of grains. The rice flour paste viscosity correlated significantly with shape (0.6148) and length (0.7353) of grains. On the basis of the established results, it was concluded that appearance of milled rice could be used as indicator for predicting gelatinization behavior: elongation ratio (length after minimum cooking time/length of the grains) of the rice grains and viscosity of rice flour during cooking.

PRACTICAL APPLICATIONS

Results from this research constitute a useful tool to predict the gelatinization behavior of milled grains and flour of japonica rice varieties, on the basis of grain appearance. The appearance is critical in acceptability of rice varieties by the consumers. The possibility to predict rice grain behavior during cooking on the basis of its appearance could be an additional attribute or market value for consumer choice. The results could be used in selection of rice variety for rice grits or flour production and use in special applications.

     

新兴城市背景下的绿道 乌托邦还是创新良机

以保加利亚的索菲亚市绿道为对象,旨在探讨绿道在新兴城市下的发展潜力。通过整合案例研究、当地规划、统计数据和法律框架等规划初期所需的理论知识与索菲亚区域内的实时现状,提出从绿色射线到特色绿轴的总体规划和"8+1战略方针",并指出对规划途径的反思和革新,都将有助于新兴城市发展趋势的本质转变,使其向着更为负责和可持续的方向发展。