A team of scientists at the Indian Institute of Technology Guwahati has developed an ultrasound-assisted fermentation method to produce a safe sugar substitute called ‘Xylitol’ from the residue left after crushing sugarcane.
With increasing awareness of the adverse effects of white sugar (sucrose), not only for patients with diabetes but also for general health, there has been a rise in the consumption of safe alternative sweeteners. According to the scientists, Xylitol, a sugar alcohol derived from natural products, has potential antidiabetic and anti-obesogenic effects, is a mild prebiotic, and protects teeth against caries.
The Research team was led by Prof. V.S. Moholkar, Department of Chemical Engineering, IIT Guwahati, and included Dr. Belachew Zegale Tizazu and Dr. Kuldeep Roy who co-authored the research papers. Moreover, the findings of the study were published in two peer-reviewed journals Bioresource Technology and Ultrasonics Sonochemistry.
“The use of ultrasound during the fermentation process not only reduced the time of fermentation to 15 hours (against almost 48 hours in conventional processes), but also increased the yield of the product by almost 20%. The researchers used only 1.5 hours of ultrasonication during the fermentation, which means that not much ultrasound power was consumed in the process. Thus, xylitol production from sugarcane bagasse using ultrasonic fermentation is a potential opportunity for forward integration of sugarcane industries in India,” Prof. V.S. Moholkar, Department of Chemical Engineering, IIT Guwahati, said in a statement.
Under normal conditions, the fermentation of the xylose to xylitol would take 48 hours, but the team hastened the process by subjecting the mixture to ultrasound waves.
According to the scientists, without ultrasound, only 0.53g xylitol was produced per gram of xylose, but on subjecting the process to ultrasound, the yield was 0.61g/gram of xylose.
“This number translates to 170 g of xylitol per kilogram of bagasse. The yield could be further increased to 0.66g/gram of xylose and the fermentation time reduced to 15 hours by immobilizing the yeast in polyurethane foam,” the scientists stated on Tuesday.
Although the team is excited over the findings, they are now working towards commercial implementation of the sonic fermentation.
“The present research has been carried out on a laboratory scale. Commercial implementation of sonic fermentation requires the design of high power sources of ultrasound for large-scale fermenters, which in turn requires large-scale transducers and RF amplifiers, which remains a major technical challenge,” said Prof. V.S. Moholkar in a statement.