Techno-economic feasibility analysis of blue and purple corn processing for anthocyanin extraction and ethanol production using modified dry grind process

This study performs the techno-economic analysis of simultaneous ethanol production and anthocyanins extraction from colored corn in a dry grind facility. Comprehensive models for the conventional process using dent corn and modified process for colored corn including pericarp separation and anthocyanin recovery were developed in the SuperPro designer. Ethanol production for plants processing 1113.11 MT/day of corn, were estimated 42, 37 and 35.2 million gallon/yr for yellow, blue and purple corn, respectively. Capital investments ranged between $87.9 and $100 million, with a minimum investment for the conventional plant. Irrespective of higher capital investments and gross operating costs, ethanol production cost during purple corn processing was 42% less than that of yellow corn ($0.75 vs. $1.3/gal ethanol) because of high revenue from anthocyanin extract. Annual anthocyanins extract production from blue corn was only 26.5 MT compared to 879 MT for purple corn, and the process was not economically viable. The internal rate of return for the plant processing purple corn was 21.2%, compared to only 8.7% for a conventional plant using yellow dent corn. The use of purple corn in dry grind facilities can significantly improve the process economics and provide anthocyanin extract for use in the food industry.