Researchers from the University of Bari Aldo Moro found a way to reduce bread waste and cultivate sustainable microbial starters.

Each year, one-third of the food produced globally for human consumption is wasted, ending up in landfills and emitting greenhouse gases. Among those food items being wasted is bread. One way researchers are attempting to lessen the food waste burden is to use discarded bread to create microbial starters. Repurposing discarded bread to feed microorganisms could be an easy way to kickstart fermentation in food industries, according to researchers.

To demonstrate, the team experimented with over 40 kinds of growing conditions. They wanted to find the best combination to feed various bacteria, yeast and other organisms commonly used in food fermentation. The team had to create the right bread recipe, enzymes, supplemental ingredients and the right time and temperature for incubation. The goal was to create a wasted bread medium (WBM) that matches or beats current production methods that rely on raw materials. Results showed that the most appetizing mix for microorganisms contained 50% waste bread. The estimated cost of producing WBM is one-third the cost of conventional methods.

WBM creates an opportunity for sustainable starter production in fermentation-based food industries. The process has already been scaled up for industrial processes.

Further studies are needed to determine if some components or a lack of micronutrients affect the microbial metabolism in any significant way.

A paper on this research was published in Frontiers in Microbiology.