Investigation of some physical properties related to healthy and non-brain walnuts

Given the importance of diagnosis and separation of non-brain and healthy walnuts in the post-harvest and product packing, some biophysical properties of walnuts such as geometry, density and sphericity index and the acoustic properties of walnuts was measured and analyzed in the present study. According to the results obtained in this study, there is a high accurate and reliable border between volume and Weight of non-brain and healthy walnuts. In the obtained regression line, non-brain walnuts fall under the regression line; whereas healthy walnuts fall on or top of the line. According to the statistical analysis of the sound intensity of falling walnuts onto the different targets (glass, steel plate, and wood), it was found that difference between the maximum amplitude of the recorded sound between non-brain and healthy walnuts is maximum for the woody target. This amount for glass, iron and wood obtained 0.004, 0.012 and 0.09 dB, respectively. Also the measured average sound power of walnut on woody target was more than the two other targets. Based on the results obtained in this study, a woody target can be used to build a device for mechanical diagnosis of non-brain and healthy walnuts.