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.

Coffee processing involves the separation of its different structures that are considered by-products. There is a current interest in adding new value to coffee by-products through their conversion into food ingredients. Following a biorefinery approach, coffee by-products can produce phenolic and caffeine-rich extracts and water-insoluble residues (WIRs) rich in dietary fiber. Consequently, this work aimed to study the flour and the WIR (obtained through a sustainable and optimized aqueous extraction of phenolic compounds) from the main by-product of coffee processing, the coffee cascara, investigating the chemical and functional differences among ingredients obtained from the dry and wet processing methods. Both dry and wet cascaras (in flour and WIR) presented a high dietary fiber content (46–97%), especially outstanding in the WIRs. Soluble dietary fiber was 2.2 to 3.6-fold higher (p < 0.05) in flours than in WIRs. The wet coffee cascara flour exhibited a remarkable antioxidant capacity (2.4 to 4.2-fold higher than the other products), as well as adequate techno-functional and physicochemical properties. All by-products inhibited α-amylase (62–96%) and reduced starch hydrolysis (52–97%), which was associated (r = 0.965, p < 0.05) with the differential total phenolic content found in samples (6.1–40.4 mg gallic acid equivalents per gram). Similarly, coffee cascara-based ingredients showed pancreatic lipase inhibitory properties (54–65%) and reduced the intestinal absorption of cholesterol (50–88%) and bile salts (81–90%) in vitro. In conclusion, both dry and wet coffee cascara exhibit a similar chemical composition and functional properties and could be revalued as new sustainable ingredients (flours and WIRs, and phenolic-rich extracts) following a biorefinery approach. These coffee cascara-based ingredients may exhibit beneficial health properties reducing oxidative stress and glucose and lipid absorption.