The processes of rough rice milling for increase head rice yield are depending on several factors. The paddy rigidities are the one of these is effect to head rice yield. In the past research papers were showed that the qualities of milling were measuring from head rice yield and rigidities of rough rice were rerated to head rice yields. In this research aim to test the rigidities of the white rice with the bending test and showing the relation between white rice rigidities and head rice yield. The PTT1 RD41 RD31 and RD49 rice varieties were used in the experiment. The result showed that the high relation between the brown rice yield and head rice yield with determination coefficient was 0.81and the brown rice yield was heavy weight more than the head rice yield about 20%. The determination coefficient between the white rice rigidities and head rice yield was 0.16 showed that the less relation.

This research report is manipulated that summarized the moment of research project in the subject of “The optimal image processing for paddy studies: Variety classification and rice kernel damage inspection”. This project had been take time in 12 mounts. We focused on rice variety classification and rice kernel damage inspection. We also investigated the apparent friction of rice surface. Results showed that area and size were the quantities that have the potential to classify rice variety and also rice kernel damage inspection. In addition we also found that geometric mean diameter performed characteristic to apparent friction of rice surface in kerosene. These results have the potential to be the basis information in terms of developing instrument for quality control and variety classification of cereal.

During the rice processing the possible situations of rice kernel cracking and breakage are commonly occurred and these consequences cause a low marketing price. According to this issue the real-time observation and together with the knowledge base of mechanical properties should be essentially helpful in detection of these defect observations. The objective of this work was established to study the mechanical stress-strain properties of rice kernels via our in-house pneumatic system design. We found that stress-strain of RD6 RD15 Phitsanulok 2 and Khao Dawk Mali 105 were greater than KhaoYipun DOAI with moisture content of 20% w.b. These results tentatively indicated the mechanical stress-strains occurred were from the difference of rice shapes. Moreover we could recognize that the characteristics of these various shapes significantly followed the scaling law of the relation between strain and time. We also found that the breaking force was different value for rice varieties. This parameter obtained can be such a high potential approach that can be used for further developing in the quantitative classification of rice varieties.