Coffee filter blocks particle size 20+ micron. If you pass the store bought juice
through this filter and there is fiber left in the filter paper and juice looks more
transparent ,then it means you have removed some fiber. I remember reading that
there are enzymes naturally present in orange that breaks down pectin.
They do not have to use external enzyme to do that. Another option is to
use frozen concentrate, they usually remove all the fibers in that.
RP mentioned that he used to buy frozen concentrate OJ and later found out
they were using enzyme. You can buy pectinase from amazon and that
will give you clear juice without pectin.
http://www.amazon.com/Pectic-Enzyme-pow ... =pectinase
I am not sure if this will work on juice,which has already used enzyme to break down pectin.
But, you can experiment with it.