TU Dublin Researchers Turn Bread Waste into Future Proteins for National Stop Food Waste Day
To mark National Stop Food Waste Day on Sunday, 1st March, researchers at the TU Dublin Food Innovation & Health Research Centre are spotlighting how discarded bread and bakery products can be transformed into valuable new protein sources through the EU-funded InnoProtein project.
While households are urged to waste less, TU Dublin researchers are addressing what happens when waste can’t be avoided. The InnoProtein project explores how surplus bread, biscuits and other bakery by-products can be used as raw materials to grow sustainable proteins for food, animal feed and bio-based products.
Dr Rena Barry-Ryan, Principal Investigator on InnoProtein at TU Dublin, explains:
We are taking food waste streams from the baking sector and using biological systems such as fungi, bacteria, insects and microalgae to convert them into valuable resources. Instead of sending bread waste to landfill, we can transform it into ingredients for food and feed, biodegradable materials and even bio-stimulants.
A central aim of InnoProtein is the development of protein-rich biomass by valorising food industry by-products. Bakery waste and cereals are used as feed substrates for insect larvae and single-cell proteins to create alternative protein products.
Insects such as Hermetia illucens (black soldier fly) and Tenebrio molitor (yellow mealworm) are fed bread and biscuit waste. These species efficiently convert carbohydrates into high-quality protein, lipids and micronutrients, offering a lower environmental footprint than conventional livestock.
Alongside insects, the project is using solid-state fermentation with traditional food fungi such as Aspergillus oryzae and Aspergillus sojae. These organisms grow on low-moisture bakery waste to produce fungal biomass rich in protein, drawing on techniques long used in foods like tempeh and soy sauce, but now applied to circular economy solutions.
Other work focuses on bacterial and microalgal fermentation. Bread waste is dried, milled and used as a carbon-rich feedstock for controlled bioreactor processes. Selected bacteria and microalgae species rapidly convert the sugars into biomasses rich in proteins, essential amino acids, and lipids.
After cultivation, the biomass is harvested and processed into high-protein ingredients suitable for food and feed applications. All organisms and processes undergo strict EU safety testing, including checks for contaminants, allergens and nutritional quality.
Dr Maame Ekua Manful, Postdoctoral Researcher on the safety and regulatory aspects of bacterial and microalgal derived products, notes:
These technologies allow us to recover nutrients from food waste and reintroduce them into the food chain in a safe and sustainable way.
PhD researcher Nicola Sunderland adds:
By using fungi and insects, we’re showing that waste bread can become a resource for high-value protein products rather than a disposal problem.
The work aligns closely with the goals of National Stop Food Waste Day, which encourages people to make small changes at home to save money, time and environmental impact. While prevention remains the priority, research like InnoProtein demonstrates how unavoidable food waste can be repurposed within a circular bioeconomy.
The InnoProtein project is funded by the European Union and the Circular Bio-based Europe Joint Undertaking and aims to meet growing demand for sustainable, nutritious protein sources for both human consumption and animal feed.
As Ireland focuses on reducing bread waste this March, TU Dublin’s Food Innovation & Health Research Centre is showing how yesterday’s loaf could help feed tomorrow’s world.