Continuous ethanol production by fermentation of waste banana peels using flocculating yeast

Warana Agricultural Goods Processing Co-operative Society (WAGPCOS), a unit producing banana puree at Amritnagar gives out the banana peels along with the foul bananas as a major waste. This waste was tested for its sugar con tent and was found to contain substantial amount of sugars with hardly any hazardous material for the fermentative microorganisms i.e. yeast. To utili ze this waste as a fermentation substrate, extract was prepared from the wa ste. Highly flocculant yeast Saccharomyces uvarum (NCIM culture 3528) havin g a high fermentation activity was used for the fermentation. A multi vesse l system was prepared for the fermentation of waste extract. The system con sisted of a main reactor, a buffer vessel and a separation vessel. The ferm entation was carried out under anaerobic conditions with CO, bubbling and w ell maintained pH and temperature. Runs wen carried out at different feed r ates with continuous yeast eel recycle. It was observed that the waste bana na peels are capable of providing enough sugar for the fermentation and hen ce can be economically utilized for the ethanol production. After the remov al of the extract from the waste, the remaining fibrous material can be dri ed in an easier way and can prove to be a good fodder for the animals.