Fermentation Dynamics During Production of Bhaati Jaanr, a Traditional Fermented Rice Beverage of the Eastern Himalayas

Abstract

Bhaati jaanr is an inexpensive high calorie mild-alcoholic beverage prepared from steamed glutinous rice, consumed as a staple food beverage in the Eastern Himalayan regions of Nepal, India and Bhutan. In this paper, fermentation dynamics including growth kinetics and physico-chemical changes during fermentation of bhaati jaanr were studied. The population of filamentous moulds declined significantly (P < 0.05) each day and finally disappeared after the 5^th day. The load of yeasts increased significantly (P < 0.05) from 10⁵ cfu/g to 10⁸ cfu g⁻¹ within two days. Lactic acid bacteria (LAB) increased significantly (P < 0.05) from 10⁶ cfu g⁻¹ to 10⁷ cfu g⁻¹ in the first day and decreased significantly (P < 0.05) to 10⁵ cfu/g at the end of the fermentation. The pH decreased and acidity increased during fermentation. The alcohol content increased significantly (P < 0.05) up to 10% on the tenth day. The reducing sugar content increased significantly (P < 0.05) until the third day and then decreased, followed by a decrease in total sugar content. Maximum activities of saccharification and liquefaction of rice were observed on the third day of fermentation. It was revealed that Saccharomycopsis fibuligera and Rhizopus spp. play important roles in the saccharification process of rice in bhaati jaanr fermentation. The mean pH, acidity, moisture and alcohol content of the product were 3.5%, 0.24%, 83.4% and 5.9%, respectively.

Key Words:

• Bhaati Jaanr
• Fermented Rice Beverage
• Moulds
• Yeasts
• Lactic Acid Bacteria

ACKNOWLEDGEMENTS

Authors gratefully acknowledge the financial support of the Department of Biotechnology, Ministry of Science and Technology, Government of India.

Notes

Data represent the means (± SD) of 5 samples¹, 15 samples² and 3 samples³, respectively. % DM (g 100 g⁻¹ dry matter basis).