Effect of the clarification pH of sorghum juice on the composition of essential nutrients for fermentation

Abstract

The growing demand to replace fossil fuels with renewable alternatives has generated an urgent and imminent global need to find new non-fossil sources. Sweet sorghum is widely recognized as a highly promising biomass energy crop with the particular potential to complement sugarcane for ethanol production. Our aim in this study was to evaluate the influence of pH during the clarification process on the composition of essential nutrients in the sorghum juice and observe how this affects the efficiency of the ethanol fermentation process. We found that a higher pH directly affected residual concentrations of key nutrients (P, Ca, Zn and Mn) and consequently the efficiency of ethanol fermentation. In conclusion, we recommend a clarification procedure at pH 6-6.5 in order not to significantly affect nutritional parameters important for the yeast fermentation process.

Sweet sorghum: broth clarification with enzymatic treatment increases the quality of the fermentation wort for ethanol production

“…From an agronomic viewpoint, the crop has a similar potential to some varieties of sugarcane grown under irregular conditions (Costa et al 2018), as well as a high content of glucose, fructose, sucrose, and fiber in its stalks (Barcelos et al 2016). Industrially, the sweet sorghum has a fully mechanized crop planting and harvesting similar to those used by the sugarcane sugar mills, and its viability is similar to the sugarcane (Durán et al 2018), including the use of commercial yeast for fermentation, ability to use bagasse as a source of energy, electricity cogeneration, second-generation ethanol, and a favorable energy balance (Dar et al 2018).…”