"Doug Kanter" wrote in message
...
"Knack" wrote in message
ink.net...

"Doug Kanter" wrote in message
...

wrote in message
ups.com...
The best example is with red delicious apples purchased at your local
grocery store.
The apples have whitish areas/stains on the outside skin, and on red
apples the white stains are especially visible. It is difficult to
remove the stains even when trying to rub them off
under running water. When soaked in water for 10 mins the whitish areas
become even
more visible. I assume they are wax, and the type of wax used on apples
supposed to be
water soluble and easily removable and these stains one is NOT. I do
not want to eat apples with pesticides and other dirt under the wax.

These stains are on apples no matter where you buy them. Is there any
way to remove the wax quickly and reliably? Does it make sense to peel
each apple?


It's easy to remove. Get yourself a fingernail brush that you'll use
just for fruits & vegetables. Put a drop or two of dish soap on the
brush and scrub, then rinse (obviously). It won't hurt the apple, but it
will remove the wax. Besides seeing that it's gone, you'll notice that
the skin suddenly has an apple smell.

Dish liquids contain surfactants that are chosen principally as
oil-in-water emulsifiers. They are *not* wax solvents, and are only OK
wettng agents.

It's odd though, how well they work at removing the wax, although the
brush is an equal partner in this process. Believe me when I tell you that
the was *IS* removed. If you'd like to repeat the experiement, be sure to
use Dawn dish liquid, original verson.

Just did some quick research. Apples are washed clean of dust and
agricultural surface contamination before they are coated. The type of wax
used on apples is not paraffin, which is derived from petroleum, but
carnauba, which comes from the leaf of a particular species of Brazilian
palm tree (Copernica cerifera). The carnauba is dissolved in a solvent named
morpholine, which functions as a coupling agent between organic and aqueous
systems. Thus the solution of carnauba in morpholine is miscible in water,
which enables the wax coating to be applied by an aqueous spray at room
temperature or via an aqueous dip bath. The liquid coating is dried quickly
by hot air treatment. All of the aforemented steps are done via a multi-step
automated process, without human contact.

I can now understand how Dawn Original can be helpful in removing the
coating, as carnauba is easier to wet than paraffin. However, I've tested
some inferior brands of fruit/vegetable spray cleaners for the consumer
market, and even some of these dedicated use products were unable to produce
"sheet wetting" on a coated apple. I didn't bother to further test them via
scrubbing, as I want a cleaner that I could simply spray on and rinse off,
without much labor.

Apparently there are trace amounts of morpholine residue in the
predominately carnauba coating. However I think the main health hazard is
not the morpholine, but the contamination from human contact which occurs
when:
1) apples are loaded into the store bins and
2) are inspected/handled by customers.

Certainly it is best to completely completely strip away the wax coating
rather than clean the surface of that coating, as not only would the
morpholine trace be removed, but also whatever contaminates that have been
trapped *into* the soft coating while the apples were in the store.

Whenever I see the smaller cheaper apples that are prebagged in plastic by
the grower or silo, I choose those. I figure that they must be cleaner than
individually displayed apples. Costco stores now offer large premium quality
apples at sharply discounted prices that are sold in clear plastic clamshell
packaging. But if not for the fact that my area also has a waste-to-energy
plant ("burn plant" for generating electricity) I would never buy those.