Incorporation of probiotics to develop millet-based alcoholic beverage : optimization, characterization and enhancing the bioactivity | |
| Author | Maharjan, Shreyasha Singh |
| Call Number | AIT Thesis no.FI-25-05 |
| Subject(s) | Millets--Nepal Alcoholic beverages Probiotics |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Innovation, Nutrition and Health |
| Publisher | Asian Institute of Technology |
| Abstract | This study aimed to develop a functional millet-based alcoholic beverage through microbial fermentation, focusing on nutritional enhancement and process optimization. Sorghum millet, selected for its high antioxidant potential, dietary fiber content, and gluten free properties, was malted through soaking, germination, and kilning at four temperatures (45 °C, 55 °C, 65 °C, and 75 °C). The effects of kilning temperature on proximate composition, total phenolic content (TPC), and antioxidant activity (DPPH) were assessed to identify the optimal brewing condition. Kilning at 65 °C produced the most balanced nutritional and functional profile and was selected for subsequent fermentation studies. In the second phase, the malted wort from 65 °C-kilned sorghum millet was fermented with Saccharomyces cerevisiae US-05 for nine days. Fermentation kinetics were monitored through pH, reducing sugar, alcohol by volume (ABV), viable yeast count, TPC, and antioxidant activity. The yeast fermentation achieved 3.55% ABV, a viable count of 6.8 × 10⁶ CFU/mL, and 68.2% DPPH inhibition, confirming robust fermentation performance and retention of bioactive compounds. The third phase applied sequential co-fermentation, wherein the wort was first inoculated with Lactobacillus plantarum and fermented for 24 hours before yeast inoculation. Parameters such as pH, titratable acidity, reducing sugar, microbial viability, TPC, and DPPH activity were measured at multiple intervals. Co fermentation resulted in greater acidification, improved phenolic release, and higher antioxidant retention compared to yeast-only fermentation, indicating synergistic effects between lactic acid bacteria and yeast. Overall, the findings highlight sorghum millet’s potential as a sustainable substrate for functional alcoholic beverage production. Sequential co-fermentation demonstrated notable improvements in functional quality, suggesting its applicability for health-oriented fermented drink development and value addition to underutilized grains. |
| Year | 2025 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Innovation, Nutrition and Health (FI) |
| Chairperson(s) | Anal, Anil Kumar |
| Examination Committee(s) | Ghimire, Anish;Himanshu, Sushil Kumar |
| Scholarship Donor(s) | AIT Scholarship |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2025 |