Uncertainty measurement in the homogenization and sample reduction in the physical classification of rice and beans

Incerteza de medição na homogeneização e redução de amostra na classificação física de arroz e feijão

ABSTRACT:

The study aimed to i) quantify the measurement uncertainty in the physical tests of rice and beans for a hypothetical defect, ii) verify whether homogenization and sample reduction in the physical classification tests of rice and beans is effective to reduce the measurement uncertainty of the process and iii) determine whether the increase in size of beans sample increases accuracy and reduces measurement uncertainty in a significant way. Hypothetical defects in rice and beans with different damage levels were simulated according to the testing methodology determined by the Normative Ruling of each product. The homogenization and sample reduction in the physical classification of rice and beans are not effective, transferring to the final test result a high measurement uncertainty. The sample size indicated by the Normative Ruling did not allow an appropriate homogenization and should be increased.

Key words:
ISO / IEC 17025; grain classification; quality control; precision