Spent coffee grounds: A review on current utilization

Abstract Coffee, one of the world’s most popular beverages, carries with it a large economic and environmental burden in the form of spent coffee grounds (SCG), the unutilized portion of the coffee bean left after brewing. However, while currently unrealized, this waste stream has the potential to be converted to various high-value bio-products. Potential uses for SCG range from energy, to nutraceuticals, and construction materials. This paper outlines the possible uses of SCG as a promising green source and reviews the most recent results from studies being done to valorize SCG.

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