Enhanced Biohydrogen Production from Food Waste via Separate Hydrolysis and Fermentation: A Sustainable Approach

Biohydrogen production from renewable resources holds promise for sustainable energy generation. This study explores the potential of utilizing food waste, a prevalent global environmental issue, as a substrate for efficient biohydrogen production. Two predominant biological methods, dark fermentation and photosynthesis, were evaluated for their feasibility in harnessing carbohydrates from food waste. Dark fermentation emerged as a more practical option due to its lower energy requirements and absence of light limitations.

The utilization of food waste as a substrate for biohydrogen production offers a dual benefit of addressing waste disposal challenges and providing an alternative energy source. With over a billion tons of food waste generated annually, accounting for a substantial portion of global food production, its high starch and protein content makes it an economically attractive source for biofuel production. The complexity lies in breaking down macromolecules, such as starch and protein, into utilizable forms (glucose and free amino nitrogen) through hydrolysis, a rate-limiting step in most bioprocesses.

To overcome the hydrolysis limitation, a separate hydrolysis and fermentation approach is proposed. Pretreatment techniques are employed to optimize the conversion of complex substrates in food waste into nutrient-rich solutions. This approach not only enhances the efficiency of the hydrolysis stage but also promotes overall biohydrogen production rates. The operating conditions during pretreatment can be tailored to maximize the conversion efficiency, thereby mitigating the challenges associated with substrate complexity.

In conclusion, this study highlights the potential of harnessing food waste for biohydrogen production through dark fermentation, providing a dual solution to waste management and renewable energy needs. The proposed separate hydrolysis and fermentation approach offers a practical strategy to optimize nutrient conversion and increase biohydrogen yields. As the world grapples with both environmental and energy challenges, this sustainable approach could play a pivotal role in shaping a more eco-friendly and energy-efficient future.

Acknowledgments: PN23150401 – The cascade valorisation of agro-industrial waste of plant biomass type in bioproducts with added value in the circular bioeconomy system.