Study on the antioxidant properties of robusta and arabica coffee silverskin by-product with different degrees of grinding

• Type: Article in International Scientific Journal
• Date: 2026

Authors

Hes, M (Author) Other; Kucharski, J (Author) Other; Alves, RC (Author) Other; Machado, S (Author) Other; Beatriz B P P Oliveira (Author) FFUP; Ariyarathna, P (Author) Other; Walkowiak, J (Author) Other; Dziedzic, K (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: FUTURE FOODS

Vol. 13

ISSN: 2666-8335

Indexing

ISI Web of Knowledge - 0 Citations

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Other information

Authenticus ID: P-01A-VMG

DOI: 10.1016/j.fufo.2025.100885

Abstract (EN): This study evaluated the effects of coffee silverskin cultivar (Arabica and Robusta), grinding degree (<95 mu m, 95-132 mu m, >132 mu m), and extraction solvent (water, ethanol) on the recovery of caffeine, chlorogenic acids, and antioxidant activity. Samples were analysed using HPLC, Folin-Ciocalteu, and antioxidant assays: DPPH and FRAP (ethanol-dependent), ABTS and metal chelation (water-dependent). Robusta contained significantly higher caffeine (6604-10,534 mu g/g) than Arabica (4550-8550 mu g/g), while caffeine content did not differ with solvent. Intermediate particle size (95-132 mu m) maximized caffeine extraction, while coarse particles (>132 mu m) yielded more chlorogenic acids. Cultivar and grinding degree had minimal influence on Total phenolic content (TPC) of water extracts; however, Robusta exhibited higher TPC (44.3-79.9 mg GAE/g dry matter) in ethanol extracts. Robusta exhibited the highest antioxidant activities in all assays: metal-chelating (49.2 mg EDTA/g) and ABTS (462.3 mg Trolox/g) in water extracts; DPPH (142.5 mg Trolox/g) and FRAP (30.5 mM Fe-2(+)/g) in ethanol extracts. Robusta silverskin showed significantly higher soluble dietary fiber (SDF) (13.1-15.4 g/100 g dry matter), while insoluble fiber did not differ with cultivar. These findings provide a basis for optimizing silverskin valorisation and its use as a sustainable bioactive source in functional food applications.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8