Production of single cell protein from cassava by mixed culture of Endomycopsis fibuligera and Candida utills

Abstract

A study on SCP production from cassava was performed in this research to find a suitable condition using Symba Yeast Process. For larger scale, experiments in a 60-litre tank were carried out to obtain essential data for process design aiming at low production cost and simple process rendering it suitable for developing countries. The cultivation of E. fibuligera and C.utilis using cassava as carbon source in a mixed culture has shown that E. fibuligera can produce amylase for starch hydrolysis yielding sugar. Glucose produced is utilized for cell synthesis as soon as it is formed. Since C. utilis is fast-growing, the process yields a product substantially of Candida yeast. The starch hydrolysis by such enzyme can be performed at low temperature (30°C) and does not demand a corrosion resistant materials for equipment. SCP can be obtained from dry cassava with a yield of 0.38 gram of dry biomass (33.8% protein content) per 1 gram of cassava. The process is as follows: dry cassava was ground to powder, dissolved in hot water at 35g/l then added 8.75 g of molasses and other nutrients. The cultivation was performed at room temperature (30°C) and pH 5.5 in a 60-litre tank equipped with two baffles and a shrouded six-flat-blade turbine at Reynolds number of 25,130 and aeration rate of 10.7 1/1 broth per hour. A starter of E. fibuligera 5097 was used at 8%v corresponding to the cell mass of 4.6 g/1. After 18 hour, C. utilis 5001 was added at 2 %v. Cell mass is finally harvested at the 39th hour of cultivation.