IIT Kharagpur Research scholar Chirasmita Panigrahi from the Department of Agricultural and Food Engineering, as part of her PhD research, has been pursuing a novel study on ozone-assisted cold sterilization technology towards the shelf stabilization of sugarcane juice without heat or chemical. Her PhD work has been recently has been selected for the NRDC National Meritorious Invention Awards 2020 by the National Research Development Corporation, Government of India, New Delhi.
Sugarcane juice has an enriched nutritional profile, which accommodates health components such as, phytonutrients, antioxidants, and vitamins (like Vitamins C&B) that offer quick relief from heatstroke, dehydration, constipation, jaundice, etc. by supplying instant energy. Owing to the absence of simple sugars and low glycemic index (30-40), its average intake by diabetic persons is also acceptable.
However, the colour and flavour unique to the juice get deteriorated immediately after its extraction due to biological processes of browning and microbial fermentation. Its short shelf life limits its long-term storage and marketing. Thermal treatments used to enhance the shelf life of sugarcane juice destroy its pleasant taste and aroma. Non-thermal methods hold promise in this regard.
The process technology being pursued by IIT Kharagpur research scholar, which is being supervised by Professor H N Mishra of the Agricultural and Food Engineering Department and co-supervised Professor Sirshendu De of the Chemical Engineering Department, involves ultra-filtering and ozonization of the freshly extracted microfiltered juice followed by packaging under an aseptic environment. The combined membrane filtration and ozone treatment technology resulted in 7 log reduction in bacteria, 5 log reduction in yeasts and moulds and 85% inactivation of enzyme polyphenol oxidase.
“This could minimize the juice fermentation and brown to a greater extent during storage. The combined technology treated juice could be successfully stored up to 12 weeks under refrigeration without any appreciable change in its bioactive and essential nutrients. The treated juice well retained its sensory characteristics especially the colour and flavour during storage,” confirmed Chirasmita.