Biotechnological Approaches to Production of Bioactives from Coffee By-Products

The interest in the application of biotechnological tools for exploitation of the food
processing wastes into value-added products has increased. The present study explored
utilization of coffee by-products for production of industrially useful enzymes such as amylase,
protease, xylanase and pectinase by solid-state fermentation utilizing fungal organisms,
Neurospora crassa, Aspergillus oryzae, Penicillium sp, and Aspergillus niger respectively,
followed by partial purification and characterization of the enzymes. The crude decolorized
pectinase obtained from coffee pulp was used in the fermentation step in robusta coffee
processing for demucilisation. The lab scale approach using this enzyme resulted in completion
of demucilage process in about of 2-3 h in case of robusta coffee compared to that of 48-72 h
period required in case of natural fermentation. The coffee by-products were also explored for
extraction of bioactive compounds such as chlorogenic acid, dietary fiber and anthocyanins.
The chlorogenic acid conserve from pre-treated coffee by-products were highest in case of
silver skin (25 %) followed by spent waste (19 %) and cherry husk (17 %). The total dietary fiber
(TDF) in coffee by-products was determined and maximum yield was obtained with silver skin
(80 %) followed by cherry husk (43 %) and pulp (43 %). The coffee pulp has cyandin-3-rutinoside
as the major anthocyanin. The in-vitro studies on bioactive compounds from coffee byproducts
demonstrated antioxidant activity, α- amylase and α-Glucosidase inhibitory activity.