Ibtissam Bouhzam
University of Lleida, Spain
Title: Extraction of chlorogenic acid with antioxidant properties from spent coffee grounds using EtOH/water mixtures
Biography
Biography: Ibtissam Bouhzam
Abstract
Statement of the problem: The agricultural industry has become a critical sector in Europe. In 2020, 20% of global food production was wasted. The manufacturing of coffee results in the production of significant amounts of waste such as Spent Coffee Grounds (SCG), causing environmental problems. Spent coffee grounds are rich in polyphenols, including chlorogenic acid and can be used as an alternative to obtain those substances.
Objective: The purpose of this study is to evaluate the capacity of ethanol to extract valuable substances suchas Chlorogenic Acid (CA) that is known for its antioxidant properties by testing different proportions of EtOH/water through solid/liquid extraction.
Methods: Mixtures of ethanol/water (0%, 20%, 40%, 60%, 80%, 96%) were tested using solid-liquid extractionassisted by vortex shaken and ultrasound (at room T and at 50°C). A solvent/SCG ratio is 5.7 mL/g, with only1 min extraction time were used. Quantification of CA was conducted in a HPLC equipped with a UV/Visiblediode at a wavelength of 278 nm. The mobile phase was consisted of acetonitrile 7% v/v and 93% v/v water. Results: Vortex yielded the greatest amount of chlorogenic acid with 0.696 mg CA/g, using 0% ethanol. The extract obtained with 20% ethanol presented similar results of chlorogenic acid, approximately, 0.528 mg CA/g (Figure 1).
Conclusion: Vortex presented the best results in comparison to ultrasound with 70 % of difference. This will help to scale the process easily. The extract obtained with 20% ethanol gave yields of chlorogenic acid that are comparable to those obtained with water. This would be interesting to reduce the amount of energy needed in solvent elimination for further applications of the obtained chlorogenic acid. It will be worth comparing both options from an environmental point of view to know which of them is environmentally better for a certain application.