Critical Evaluation of Coffee Pulp as an Innovative Antioxidant Dietary Fiber Ingredient: Nutritional Value, Functional Properties, and Acute and Sub-Chronic Toxicity

Abstract

Coffee pulp is a by-product generated during coffee processing, producing environmental pollution when discarded in rivers. The revalorization of coffee by-products is currently being studied due to their high potential as new value-added food ingredients. This work aims to explore the chemical composition and functional properties of coffee pulp and validate its safety for use as a novel food ingredient. Coffee pulp composition was assessed following the standard methods (AOAC). Physicochemical properties, total phenolic compounds (TPC), antioxidant capacity, hypoglycemic and hypolipidemic properties were determined using in vitro techniques. Acute and sub-chronic oral toxicity experiments were carried out following OECD Test Guidelines 452 and 408. Coffee pulp showed a high content of dietary fiber (51.2%), highlighting the insoluble fraction. Proteins (9.2%) and lipids (2.6%) were considered a min fraction. Coffee pulp presented high content of TPC (40.6 mg g−1), of which 29% were linked to DF, giving coffee pulp its antioxidant potential (102.3 mg Trolox eq g−1). The by-product showed good physicochemical properties. Coffee pulp reduced the absorption of cholesterol (84%) and bile salts (85%), inhibited pancreatic lipase (64%), and presented the capacity to diminish the diffusion of glucose (34%). The intake of coffee pulp did not cause significant lesions in vital organs. In conclusion, the coffee pulp could be used as a potential ingredient with beneficial health properties.