Re: Rancid oil (Re: Ultrafine Clear Film and Epson 2200

This is sooo very OT, but one time I made a really great ratatouille, and I
ran out of olive oil so I went across the street and borrowed some of my
mother in law's (who never cooks). Whoaaaa, mama. Apparently the olive oil
was years old, because the ratatouille was inedible due to the rancidity of
the olive oil. I can't believe I didn't taste it while cooking or trust my
nose, before I ate it. I had never experienced rancid oil before that
moment. And yes, it was the oil and not my cooking, because I then tasted
the olive oil from the bottle and I about barfed.

Now her daughter goes through her cupboard and writes dates on items that
have no expiry date, or just throws the stuff out if no date is visible and
there is any question. You know things are bad when the Campbell's soup
label is from back in Andy Warhol days...but I exaggerate.

I know in the printmaking lab they use baby oil (which I think is just
mineral oil with baby butt smell added) to oil paper negs. The exposure
times with these in relation to transparencies is 6 1/2 mn vs 4 mn 15 secs
approximately, on silkscreen (is this diazo?), so only a 50% increase in
time. After a while my prof said they lose their transparency, so one needs
to reoil. Apparently, from below, Katharine, you never reoil, so it is
another myth?

Paraffin and beeswax should not go rancid. I used to use those for bw print
paper negs. But this requires an iron.
Chris

> My experience with rancidity is that it depends on the oil. The first
> oil I used, a generic vegetable oil from the grocery store, turned
> rancid, and no myth about it. I don't remember whether it was days or
> weeks, but within a short time the negatives developed a distinct
> rancid odor, which was pronounced enough to knock one backwards a bit
> when opening the file box containing these negatives. This odor lingered
> for a couple of years and then faded, but at the same time the odor
> faded, the paper turned brown rendering the negatives useless as
> negatives; a short time after beginning to turn brown they became
> brittle and would fall to bits at a touch.
>
> At the first hint of rancidity, I cast about for a better oil and
> settled on mineral oil; I have mineral-oiled negatives that are a
> decade or more old and as fresh today as when they were new.
>
>
> Katharine
>
Received on Fri Oct 22 08:08:22 2004