Evaluating Kernza (Thinopyrum intermedium) as a Co‐Fermentation Feedstock for Bioethanol Production

Background: Kernza (Thinopyrum intermedium), a perennial grain developed by the Land Institute, presents a promising alternative to conventional ethanol feedstocks due to its deep-root systems, low fertilizer requirements, and carbon sequestration potential. Objectives: This study evaluates the fermentation performance of Kernza, alone and in combination with corn, under two temperature conditions (25°C and 30°C). Five substrate ratios were tested using Saccharomyces cerevisiae: 100% corn, 75%:25% corn-Kernza, 50:50, 25:75, and 100% Kernza. Methods: Ethanol yield was estimated via CO2 weight loss corrected for evaporation. Carbohydrate availability was derived from literature values. Statistical analysis examined the effects of substrate composition and temperature on ethanol production. Results: The 75:25 corn-Kernza blend at 25°C produced the highest ethanol yield, suggesting synergistic interactions. Conversely, higher Kernza proportions reduced yield, likely due to its higher fiber and low starch content. pH monitoring indicated that Kernza inclusion influenced medium buffering. Conclusion: Kernza is a viable supplemental feedstock when used in moderate proportions with corn. Further optimization, including enzymatic pretreatment, may enhance its fermentation potential.