The anti-oxidant properties of coffee skin has been discovered in a new study which quantified the powerful antioxidant and antimicrobial properties of coffee grounds and silverskin. Silverskin is the epidermis of the coffee bean and is usually removed during processing, after the beans have been dried, while the coffee grounds are normally directly discarded.
These by products have previously had very little practical uses, except as homemade skin exfoliants or as abrasive cleaning products. They are also known to make great composting agents for fertilizing certain plants.
The research study published in the academic journal of Food Science and Technology, demonstrated the impact of these substances which are rich in fibre and phenols. The research findings reveal that the antioxidant effects of these coffee grounds are 500 times greater than those found in vitamin C and could be employed to create functional foods with significant health benefits.
“They also contain high levels of melanoidins, which are produced during the roasting process and give coffee its brown colour. “The biological properties of these melanoidins could be harnessed for a range of practical applications, such as preventing harmful pathogens from growing in food products”, said Professor Rufián Henares.” “If we are to harness the beneficial prebiotic effects of the coffee by-products, first of all we need to remove the melanoidins, since they interfere with such beneficial prebiotic properties.”
Ana Jiménez-Zamora, Silvia Pastoriza, José A. Rufián-Henares. Revalorization of coffee by-products. Prebiotic, antimicrobial and antioxidant properties. LWT – Food Science and Technology, 2015; 61 (1): 12 DOI: 10.1016/j.lwt.2014.11.031