This paper has demonstrated the feasibility of utilising waste
bread as a genetic feedstock for the production of SA as a valueadded
product. The results showed that solid-state fermentation of
waste bread pieces can be successfully used to process waste bread
for the production of nutrient rich hydrolysates. Experimental studies
showed that the empirical first-order kinetic model could be
used to predict the amount of glucose and FAN liberated during the
simultaneous hydrolysis and fungal autolysis reactions.
Bread hydrolysate was subsequently used for the fermentative
production of succinic acid by A. succinogenes as part of the
proposed bioprocess. The results demonstrated that the bread
hydrolysate contains sufficient nutrients to support A. succinogenes
growth and SA production. The resultant SA concentration was
47.3 g/L SA and an overall yield of 0.55 g SA/g bread, which is the
highest among other food waste-derived media reported. Although
SA was selected as the test case, thousands of other value-added
products could be produced from waste bread. This could reduce
the dependence of petroleum for chemical production. Therefore,
it would be beneficial to explore other profitable products in
future studies. Finally, it can be suggested that the utilisation of
waste bread for the production of value-added products should be
seriously considered by local governments as part of their strategy
for tackling the MSW problem and for the environmentally friendly
production of chemicals, materials and fuels.