2. Materials and methods
2.1. Materials
Non-ionic surfactant sorbitan monooleate (Span 80) was procured
from Loba Chemie, Mumbai, India. Absolute ethanol, hexane
and heptane were purchased from Merck, Mumbai, India. Analytical
reagent grade chemicals were used throughout this study.
Grape wine (Goana’s wine) was purchased from John Distilleries
Pvt. Ltd., Bangalore. All reagents and the wine were used directly
as received from the manufacturer.
Aqueous alcohol solution was prepared by mixing 4 ml absolute
ethanol in 96 ml (v/v) double distilled water. This 4% alcohol solution
was used as feed solution for optimization of extraction
parameters using liquid emulsion membrane.
Fresh red cabbage, beetroot and banana bract were purchased
from a local market. The vegetables were ground using domestic
hand mixer with addition of required volume of 15% alcohol solution.
Alcohol was added during mixing, for better extraction of color.
The extracted juice was filtered through muslin cloth and
centrifuged (6500 rpm, 10 min) to remove the suspended particles.
The colorant solution, thus obtained containing alcohol, was used
as feed.