Alcoholic fermentation of sorghum without cooking

Area of Science:

• Agricultural Science
• Biotechnology
• Fermentation Technology

Background:

• Sorghum is a significant crop in Thailand, rich in fermentable sugars.
• Traditional alcoholic fermentation often involves cooking, which can be energy-intensive.
• Exploring raw sorghum fermentation offers a potentially more efficient bioprocess.

Purpose of the Study:

• To evaluate the potential of two Thai sorghum varieties (KU 439 and KU 257) for raw alcoholic fermentation.
• To determine the optimal sorghum concentration for maximizing alcohol yield.
• To assess the efficiency of alcohol production based on theoretical starch content.

Main Methods:

• Raw sorghum (varieties KU 439 and KU 257) was used as the substrate for alcoholic fermentation.
• Fermentation was conducted without a cooking pre-treatment step.
• Sorghum concentrations ranging from 30-35% (w/v) were tested in the fermentation broth.

Main Results:

• Both KU 439 and KU 257 sorghum varieties contained high levels of total sugar (80.0% and 75.8%, respectively).
• Optimal sorghum concentration for fermentation was determined to be between 30-35% (w/v).
• Alcohol yields of 13.0% (v/v) and 12.6% (v/v) were achieved for KU 439 and KU 257, respectively, with high theoretical yields (84% and 91.9%).

Conclusions:

• Raw alcoholic fermentation of Thai sorghum varieties is feasible and efficient.
• Sorghum varieties KU 439 and KU 257 are suitable substrates for producing high yields of alcohol.
• Optimized fermentation parameters allow for significant alcohol production without cooking.