Abstract:
Solid State Fermentation (SSF) is a form of solid substrate fermentation with low humidity levels. This study
aims to determine the maximum time of the fermentation process to produce ethanol with SSF method and
studying the kinetics of cell growth of Zymomonas mobilis for variations in particle size of the substrate.
Pineapple peel waste is used as a raw material with a variety particle size of substrate in the form of slurry, 1x1
cm and 2x2 cm. Time of fermentation sampling conducted in 6; 12; 18; 24, 30, and 36 hours. Environmental
conditions Zymomonas mobilis growth adjusted to pH 5 and 30 ° C. Analysis carried out in the study is the
analysis of ethanol content using alcoholmeter and calculation of the number of cells by turbidity method using
UV spectrophotometer to determine the kinetics of cell growth of Zymomonas mobilis. The maximum time
obtained in this study was 24 hours for all particle size of the substrate. In fermentation process with the SSF
method, the kinetics of cell growth of Zymomonas mobilis and ethanol concentration is influenced by the
particle size of the substrate. The highest ethanol concentrations obtained was 33% V on substrate particle size
slurry with maximum specific growth rate 0,43/hour
