Antioxidant
effects of coffee by-products 500 times greater than vitamin C
University of Granada, Science
Daily
The coffee industry plays a major role in the global economy. It
also has a significant impact on the environment, producing more than 2 billion
tonnes of coffee by-products annually.
Coffee silverskin (the epidermis of the coffee bean) is usually
removed during processing, after the beans have been dried, while the coffee
grounds are normally directly discarded.
It
has traditionally been assumed that these by-products ─ coffee grounds and
coffee silverskin, have few practical uses and applications. Spent coffee
grounds are sometimes employed as homemade skin exfoliants or as abrasive
cleaning products. They are also known to make great composting agents for
fertilizing certain plants.
But apart from these limited applications, coffee by-products
are by and large deemed to be virtually useless. As such, practically all of
this highly contaminating ‘coffee waste’ ends up in landfills across the globe
and has a considerable knock-on effect on the environment.
In
an article published in the academic journal Food Science and
Technology, the researchers
demonstrate the powerful antioxidant and antimicrobial properties of the coffee
grounds and silverskin, which are highly rich in fibre and phenols.
Indeed, their findings indicate 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.
Moreover,
Professor Rufián Henares points out: “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.”
However, he also adds: “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.”
The
researchers conclude that processed coffee by-products could potentially be
recycled as sources of new food ingredients. This would also greatly diminish
the environmental impact of discarded coffee by-products.
The
Ministry of Economics and Finance has recently allocated a new research project
to the team under the ‘State R&D programme’, in order to enable them to
conduct further studies in the area and re-assess the potential value of coffee
by-products.
Story Source:
The
above story is based on materials provided
by University of
Granada. Note: Materials
may be edited for content and length.
Journal Reference:
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
Cite This Page:
University of Granada. "Antioxidant effects of coffee
by-products 500 times greater than vitamin C." Science Daily,
7 May 2015. <www.sciencedaily.com/releases/2015/05/150507082525.htm>.