A primary concern regarding the role of biomass in America's energy future is the debate regarding land devoted to food vs fuel. Critics claim that dedicated energy crops will reduce the amount of land available for human use, raising food prices or causing shortages. In addition, the large biorefineries needed to obtain process economies will require large tracts of farmland, making the logistics of the supply chain difficult. To address these issues, we propose a regional approach to biomass treatment, which can be used to enhance the value of biomass for both animal feed and ethanol production. Thus, land can be used for feed and fuel simultaneously, and the logistical supply problems can be significantly reduced.

In this study, we use ammonia fiber expansion (AFEX) pretreatment in conjunction with alkaline extraction and subsequent coagulation of proteins to co-produce a highly digestible lignocellulosic product and a high quality rumen bypass protein product from orchardgrass (Dactylis glomerata L., Baridana cultivar) and switchgrass (Panicum virgatum, Cave-in-rock cultivar). Protein extraction conditions (temperature, pH, residence time) will be optimized for both types of grasses, as well as the effect of additional additives such as surfactants. In addition, the effect of drying the grass, as well as the effect of AFEX pretreatment, will be studied in relation to the amount of protein obtained. Further protein processing may be necessary to decrease the degradation of protein within the rumen, thus enhancing the quality and therefore value of the final product. Heat coagulation in the presence of reducing sugars will be used to simultaneously concentrate and treat the protein extract, and the quality of the final product will be determined by both the extent of degradation and the amino acid profiles. Finally, a complete mass balance will be performed for the optimal processes for both grasses, indicating the effectiveness of the concept.

Extended Abstract Status: Not Uploaded