Repurposing Fresh Coffee Husk into High-Nutritional-Value Fruit Spreads ^†

Abstract

In the coffee industry, approximately 60% of coffee fruit components are discarded after harvest, posing potential environmental challenges. To repurpose these organic by-products for human consumption, fresh coffee husks from wet coffee processing at a plantation in Tres Ríos, Cartago, Costa Rica, were used to prepare fruit spreads. Three formulations were developed, plain coffee pulp, coffee pulp with pectin, and coffee pulp with guava, each in high- and low-sugar versions (1:1 and 3:1 fruit-to-sugar ratio, respectively). The stability (moisture content, water activity, Brix, and pH), and key nutritional values (sugar profile, minerals, dietary fiber, and fat content) of these spreads were evaluated. Secondary plant metabolites, such as caffeine and tannins, and color were also analyzed. In addition, consumer acceptability was assessed using a hedonic test of the three formulations. The results showed that the high-sugar versions met stability requirements better than the low-sugar ones. Furthermore, both sugar variants had high mineral and dietary fiber contents, qualifying them for the “source of fiber” label according to European Union Food Regulation No. 1924/2006. Caffeine content was within safe limits for adult consumption at 60 mg per 20 g serving, with minimal tannin content (<0.7 mg/g dry basis). Sensory evaluation revealed a preference for the high-sugar guava formulation, followed by the high-sugar plain coffee pulp, and the lowest ratings were received for the low-sugar plain recipe. These results support the feasibility of converting coffee by-products into useful consumer products with potential health benefits and reduced environmental impact.