Stickiness is a major textural characteristic of cooked rice and an important criterion in cultivars classification. Many reports on instrumental evaluation cooked rice stickiness are based on variants of the texture profile analysis (TPA), a method that has fundamental methodological flaws and creates logical inconsistencies. Notable among these is that cooked rice tested as a flat cylindrical specimen having a larger diameter is always harder and stickier than when tested as a narrower specimen. Recent novel improvements have been the use of a universal testing machine (UTM) to record the force and calculate the work needed to separate a pre-compressed pair of individual cooked rice kernels, or to separate a single pre-compressed cooked kernel from the flat surface to which it is attached, while accounting, in both cases, for the contact areas. It is proposed to modernize an older manual method to measure the attractive force between two uncompressed cooked rice kernels directly with a tensiometer by replacing it with a UTM and expressing the result in term of a cohesion index, the dimensionless ratio between the net separation force and an individual cooked kernel’s weight. Rough calculations based on published data indicate that cooked rice of cultivars known to be sticky would have an index on the order of 15 while those known as non-sticky about 3 only, where the actual values will depend on the cooking procedure and the dry rice’s history. Also proposed is a similar adhesion index to characterize the attractive interaction of cooked rice with any surface of interest.

粘性是米饭的主要质地特征，也是品种分类的重要标准。关于仪器评价米饭黏稠度的许多报告都是基于质地轮廓分析（TPA）的变体，该方法具有根本的方法学缺陷并造成逻辑上的不一致。其中值得注意的是，作为直径较大的扁平圆柱状样品测试的米饭始终比作为较窄的样品测试的米饭更硬，更粘。最近的新颖改进是使用通用测试机（UTM）来记录力并计算分离预压缩对的单个米粒或分离单个米粒所需的功从与之相连的平坦表面预压缩煮熟的玉米粒，在两种情况下都要考虑到接触面积。提议对旧的手动方法进行现代化改造，以张力计直接测量两个未压缩的米粒之间的吸引力，方法是将其替换为UTM并用内聚指数，净分离力与单个煮熟的仁的重量。根据已发布的数据进行的粗略计算表明，已知为黏性的栽培稻米的指数约为15，而被称为非黏性的水稻稻米的指数仅为3，而实际值将取决于烹饪过程和干米的历史。还提出了类似的粘附指数，以表征煮熟的大米与任何感兴趣的表面的吸引力相互作用。