Scientists use algae to convert food waste into sustainable ingredients

Every festive season, our love for chocolate brings joy – and a mountain of waste. From discarded cocoa shells to factory offcuts, the chocolate industry faces a significant environmental challenge, contributing to carbon emissions and landfill.

What if that indulgence could also be a force for good?

In partnership with global chocolate brand Mars, King Abdullah University of Science and Technology (KAUST), in Saudi Arabia, has unveiled a discovery that offers a sweet solution to this bitter problem.

Scientists have found a way to transform chocolate factory waste and carbon dioxide into C-phycocyanin – a vibrant, natural blue colouring agent that’s completely food-safe and poised to tap into a global market valued at more than US$275 million by 2030.

An ancient strain of red algae (Galdieria yellowstonesis) literally eats the sugars from chocolate waste to grow into a protein-rich biomass. The result is a stunning blue pigment, recently deemed food-safe by the United States Food and Drug Administration (FDA), that offers a natural alternative to artificial dyes. It’s used across food, cosmetics, and pharmaceuticals.

KAUST’s method offers significant advantages over conventional pigment production, including reduced costs and increased yields. Mars’ involvement, providing chocolate samples for the research, showcases a compelling model for how major food producers can drive green initiatives.

KAUST Associate Professor Kyle Lauresen and lead author of the study (published in Trends in Biotechnology) said: “Our work studying the metabolism of algae is uncovering new ways to turn waste into valuable products sustainably.

“Chocolate production, for example, generates waste when process lines start and stop. We realised this waste could be a useful food for Galdieria.”

“Additionally, the recycling of factory waste into feed for microorganisms like algae to produce valuable products helps local industry contribute to a circular economy. This is especially relevant for food producers, who are facing increasing pressures in relation to production costs, waste management, and climate change.”

Mars Corporate Affairs Director-Middle East and Africa Obai Rahim said Mars, is committed to fostering innovation and sustainability through meaningful partnerships with leading academic institutions like KAUST.

“We are pleased that our chocolate samples could support this collaborative research, and we were delighted to welcome the KAUST team to our KAEC facility.

“This project reflects our dedication to advancing science and developing sustainable solutions, especially those that leverage local resources and expertise. The exploration of blue phycocyanin production from Galdieria grown on food waste aligns with our vision for a more sustainable future and our ongoing efforts to reduce food waste and promote circular economic practices.

“Mars values the opportunity to engage with local industry and academia, and we look forward to continuing our collaboration with KAUST to drive impactful research and innovation in the region.”

For their experiments, Lauresen and his research team collected waste from a chocolate factory in Saudi Arabia.

The researchers plan to further develop their process by assessing the scalability and technical capacity of Galdieria production processes on locally available wastes, helping more businesses in Saudi Arabia make the critical shift towards a circular carbon economy.