From Coffee Coproduct to Functional Ingredient: Coffee Silverskin Flour as a Sustainable Fat Replacer in Ice Cream and Its Impact on Nutritional, Physicochemical, and Sensory Acceptance

Abstract

This study evaluates the feasibility of using coffee silverskin flour (CSF) as a milk cream replacer in full-fat ice cream to enhance its nutritional and functional profile. Two formulations were developed by replacing milk cream with CSF at levels of 15.78% (SSIC25) and 31.56% (SSIC50). Results showed a significant reduction (p < 0.05) in fat content, decreasing from 10.14 g/100 g in the control sample to 5.91 g/100 g in SSIC50. Concurrently, total dietary fiber increased significantly from 3.22 to 7.34 g/100 g. The incorporation of CSF also enriched the mineral profile, with calcium and potassium levels increasing by 27.77% and 38.56% in SSIC50, respectively. Bioactive compounds were notably enhanced; caffeine content reached 335.25 mg/100 g, and caffeic acid derivatives reached 69.51 mg/100 g in the highest substitution level. Physicochemical analysis revealed that overrun increased significantly from 29.2% to 52.17%, while the melting rate remained unaffected. Sensory evaluation indicated that although CSF increased bitterness and grittiness, the SSIC25 formulation maintained favorable consumer acceptance scores (>6.0). In conclusion, coffee silverskin flour serves as a sustainable, health-promoting ingredient for frozen desserts, with a 15.78% replacement level identified as the optimal threshold for balancing nutritional improvement and sensory acceptance.