The effect of roasting on the antioxidant and antibacterial capacity of coffee cherry husk extract

Résumé

Abstract The coffee cherry process generates huge amounts of byproducts which are disposed of on the land, causing a serious environmental problem. The coffee cherry husk is one of the main byproducts generated from dry coffee processing, which contains many high-value and exhibits antioxidative and antimicrobial properties biomolecules including phenols, tannins and flavonoids. The primary goal of this study was to investigate the effects of roasting temperatures (150–200 °C) and times (10–25 minutes) on the yield, total phenol, tannin, and flavonoid content, as well as the antioxidant and antimicrobial capacity of an ethanol extract obtained from the coffee cherry husk using an automatic solvent extractor. In this study, the extract yield, total phenol and flavonoid content, as well as the antioxidant and antimicrobial capacity of roasted coffee cherry husk extract were enhanced by roasting. The extract yield ranged between 6.22 ± 0.08–16.37 ± 0.61%. The total phenol and flavonoid content ranged from 9.00 ± 0.03–123.49 ± 0.21 mg gallic acid equivalent/g and 2.69 ± 0.26–35.34 ± 0.13 mg quercetin equivalent/g, respectively. As roasting temperature and time increased, total tannin decreased from 42.45 ± 0.20 to 0.27 ± 0.04 mg tannic acid equivalent/g. The 2, 2-diphenyl-1-picrylhydrazyl radical and hydrogen peroxide scavenging capacities extended from 24.68 ± 0.05–93.83 ± 0.11% and 14.45 ± 0.19–76.07 ± 0.16% respectively, while the ferric reducing capacity ranged from 10.85 ± 0.09–47.02 ± 0.20 mg ascorbic acid equivalent/g. The bacterial inhibition zones extended from 7.03 ± 0.56–21.30 ± 0.27 mm and 6.00 ± 0.00–15.77 ± 0.25 mm for Escherichia coli and Staphylococcus aureus, respectively.

Citer ce document

Accès au document

Ce document est hébergé sur son dépôt institutionnel d'origine.

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0