N. Nepomuceno et al., DYNAMICS OF CHEMICAL-ELEMENTS IN THE FERMENTATION PROCESS OF ETHANOL-PRODUCTION, Journal of radioanalytical and nuclear chemistry, 216(2), 1997, pp. 289-292
Brazil has become the largest producer of biomass ethanol derived from
sugar cane. The industrial production is based on the fermentation of
sugar cane juice by yeast, inside of large volume vats, in a fed-batc
h process that recycles yeast cells. To study the dynamics of chemical
elements in each operating cycle, five stages of the fermentation pro
cess were considered: must, yeast suspension, wine, non-yeast wine and
yeast cream. For this, a mass balance of the terrigenous elements, Ce
, Co, Cs, Eu, Fe, Hf, La, Na, Sc, Sm, and Th, and the sugar cane plant
elements, Br, K, Rb, and Zn, were established in fermentation vats of
an industrial scale unit, with sampling undertaken during different c
limatic conditions (dry and rainy periods). A similar distribution of
the sugar cane characteristics elements was found for the stages analy
sed, while for the terrigenous elements a trend of accumulation in the
yeast cream was observed. Preferential absorption of Br, K, Rb, and Z
n by yeast cells was indicated by the smaller concentrations observed
in yeast suspension than in yeast cream.