Experimental Study on the Internal Stress Cracking of Rice Kernel (Part 1)

On the Method for Measuring Cracked Rice Percentage

Abstract

In order to investigate the stress cracking of rice grain during moisture adsorption and desorption (drying) processes, an examining method of rice cracking was discussed.
The experimental retults obtained were summarized as follows:
(1) The total number of severely and slightly cracked rice was little influenced by each of inspectors trained several times. The number of severely cracked rice, treated as one of damaged rice by the official inspection of Japan, was remarkably influenced by the inspectors.
(2) A x-ray technique for the examination of rice cracking could be applied effectively as well as the visual technique.
(3) After drying, the cracked rice percentage increased with preserving time of rice in an air tight container and reached the final percentage at a constant temperature within a couple of days. The final percentage depended upon the preserving temperature.
In this paper a method for measuring cracked rice percentage was proposed based on the above experimental results.