Recovery of Phenolic Antioxidants and Functional Compounds from Coffee Industry By-Products

The recovery process of the phenolic compounds
from the coffee industry by-products and their antioxidant
activity were investigated in thiswork. The coffee by-products
(coffee pulp, husk, silver skin, and spent coffee) were obtained
from coffee processing industry. The phenolic conserves were
extracted using solvent mixture of isoproponal and water. The
yield of the conserve was highest in case of silver skin (25%)
followed by spent waste (19%) and cherry husk (17%) when
pretreated with viscozyme. The conserve enclosed chlorogenic
acid as major component when analyzed with highperformance
liquid chromatography. The bioactive conserves
prepared from coffee by-products possessed 65%–70%
antioxidant activity. Apart from these, the coffee by-products
encompassed total dietary fiber of 40%–80%. Whereas the
soluble and insoluble fiber proportion of the coffee by-product
ranged between 16–35% and 18–64%, respectively. The
antioxidant activity of coffee by-product fiber ranged from
1.5 to 2.0 mmol trolox/100 g and is analogous to that of
widespread fruits and fresh vegetables. The hydration
properties such as water holding capacity of each by-product
was strictly related to the amount of insoluble fiber and to the
granulometry. This is the first report on the isolation of
bioactive and functional compounds from coffee by-products
and can be a source of new value-added products such as
phenolic antioxidant adjunct for food processing.