Innovative technologies used to convert spent coffee grounds into new food ingredients: Opportunities, challenges, and prospects

Every day, the world brews up a mountain of coffee—60 million kilograms of spent grounds, to be exact. What if that waste could become your next superfood?

Spent coffee grounds (SCG) are the overlooked hero of the circular economy. With 60 million kilograms generated daily, this by-product of your morning brew is packed with carbohydrates, dietary fiber, and protein—plus a mineral punch of potassium and magnesium. It even harbors bioactive compounds like chlorogenic acids, caffeine, and melanoidins, which may offer antioxidant, antimicrobial, and anticancer benefits. But SCG's hard-to-digest nature has kept it out of our plates—until now. Innovative technologies are stepping in to unlock its potential. Green extractions pull out valuable compounds, while hydrolysis breaks down fibers into fermentable sugars and prebiotic hydrolysates. Fermentation and encapsulation then transform these components into new food ingredients. Often, these methods are combined in sequence, creating a tailored approach to upcycling waste. The challenge? Scaling up and fine-tuning fermentation to make SCG truly digestible and delicious. Yet the promise is clear: SCG could become a sustainable ingredient, delivering both nutritional and functional perks. This systematic review maps the path forward, turning coffee waste into a resource that feeds both people and the planet.

Key Points

• 60 million kg SCG generated daily worldwide
• SCG rich in fiber, minerals, and bioactives
• Green extraction, hydrolysis, fermentation, encapsulation unlock potential