Several technologies have been recently developed and applied in dry-grind corn ethanol plants in the United States, including oil extraction from thin stillage, anaerobic digestion of thin stillage for biogas production and water reuse, as well as phytase addition before the fermentation to degrade phytate and increase the ethanol yield. Herein we evaluated downstream samples from various stages in ethanol and coproduct production from four large, commercial, dry-grind ethanol facilities to determine the composition and distribution of inositol phosphate and develop a phosphorus mass balance. The most significant change in phosphorus distribution resulted from the addition of phytase to upstream and fermentation processes, which partially degraded organic phosphorus to reactive phosphorus. The discussion presented may facilitate the understanding of phosphorus flow within an ethanol plant, indicating fractions richer in phosphorus, indicating, for instance, potential extraction pools within the ethanol industry.
Bibliographical noteFunding Information:
The authors are thankful for the financial support from MnDRIVE-Global Food Ventures Program and to CAPES for the Science without Borders Ph.D. fellowship (Process Number 13252/13-5). Authors are also grateful to ABVista (Marlborough, U.K.) for the 31P NMR analysis for inositol-phosphate distribution among ethanol coproducts.