We cannot blame the scientific community for not doing everything to push us to abandon fossil fuels: according to a study highlighted by Live Science, salvation could come… from the recovery of bread crumbs. Instead of putting them in the trash or giving them to birds, we would be well advised to store them en masse because they could be of great help to the chemical industry, explains the scientific media.
This new process, described on February 23 in the journal Nature Chemistry, combines natural fermentation by bacteria and metal catalysis to generate a range of valuable chemicals from simple food waste – particularly crumbs. The authors of the study believe that this hybrid process, generally carbon neutral, could constitute a first step towards a more sustainable chemical industry.
Cheaper than glucose
Everything starts from a reflection on hydrogenation, a fundamental chemical process in food production, plastics manufacturing and drug synthesis. Most of the hydrogen gas used in this reaction is derived from fossil fuels through a polluting and energy-intensive process called steam reforming, which produces 15 to 20 kilograms of carbon dioxide for every kilogram of hydrogen generated.
For professionals in the chemical industry, making hydrogenation greener therefore represents a major challenge in terms of sustainable development. This is what pushed Stephen Wallace, professor of chemical biotechnology at the University of Edinburgh, to study the possibility of harnessing the power of life to solve this chemical problem. The scientist assumed that many bacteria naturally produce hydrogen when forced to breathe without oxygen, releasing a constant stream of the gas into their environment.
This resulted in the idea of using this biohydrogen instead of fossil fuels, as explained by Stephen Wallace. “The main challenge was to find a catalyst that could work in a living system: in water, at moderate temperatures and without harming cells”he explains to Live Science. “We needed to find a balance between a catalyst that remains active in a complex biological environment and microbes that continue to function in the presence of the catalyst.”
After tests carried out on glucose, an interesting but expensive raw material, the teacher and his team looked for a cheaper and more sustainable alternative. The idea of using bread waste then emerged, with convincing results. The hydrogenation process using bread crumbs reduces the global warming potential by more than 135%, which corresponds to a negative carbon footprint. Ultimately, scientists hope that this method can be integrated into industrial chemical synthesis.
