Optimization on process parameters of corn germ separation with color sorter by response surface methodology

To enhance the efficiency of sorting corn germs using a color sorter and ensure the quality of endosperm residue products, experiments on sorting corn germs with a color sorter were conducted. A single-factor experiment was employed to investigate the impact of the color sorter’s flow rate, accuracy, and pneumatic valve delay time on the sorting effectiveness of corn germs. The working parameters for sorting corn germs using the color sorter were optimized through Box-Behnken central combination test and response surface methodology. The results indicated that the degree of influence on the net selection rate of the final product was in the order of accuracy> pneumatic valve delay time> flow rate, while for the error-sorting rate of the rejected material, it was accuracy> flow rate> pneumatic valve delay time. The optimal combination of working parameters for sorting corn germs using the color sorter was determined to be a flow rate of 30, accuracy 133, and pneumatic valve delay time 2.6 ms. Under these conditions, the net selection rate of the color-sorted final product was 95.44%, and the error-sorting rate of the rejected material was 10.89. The fat content of the obtained endosperm residue product was reduced to 2.13%, and the protein content was reduced to 8.80%. The research findings provide technical support for achieving optimal performance in sorting corn germs using a color sorter. By incorporating color sorting technology into the dry process of corn in conjunction with gravitation germ separation, a more ideal effect of corn germs separation can be achieved.