I was very pleased to find that the local shopping stores in
switzerland are starting to market rapeseed oil. which has a high
omega3 content. But when I shopped around, I found the following
really wierd things:

The 1st product was marked "carefully" pressed, but was in a clear
plastic bottle. There was no mention of Omega3 content, so I did not
buy it.

The 2nd product did not specify how it was pressed, but was in a dark
plastic bottle. As well there was no mention of Omega3 content so I
did not buy it.

The 3rd highlighted "Rich in Omega-3" on its front label in big
letters, and it specified the Omega3/Omega6 content. (7g/18g for
100ml). It did not mention how it was pressed, and it was in a clear
(very lightly yellowed) plastic bottle. It had icons that indicated
that it was suitable for frying in a frypan up to 180°C. I was
disapointed in being able to read that it was specially pressed, but
as there were no other products to choose from, I decided to buy it.

Then I stumbeled across a 4th product that was labeled as "carefully
pressed", in a dark glass bottle, with an icon informing that it was
suitable for pan frying up to 180°C, but not for deep frying at 180°C.
That confused me as I did not see any difference, other than in the
pan frying, how do you know or control what temperatures you reach,
but in the deep frying, there is a thermostat you can set. It claimed
to have a 8g/19g for 100ml omega3/omega6 content.

The same store had flaxseeds partially ground in a plastic bag with a
clear window showing the seeds broken displaying their white kernals.
There is no mention of omega3, and its label states that it is used as
a laxative. The doses recommended is 1-3 Tablespoons daily. It had
directions that the product should be stored in a "dry cool place (not
in the refrigerator)". I was told that that was to prevent
condensation from forming.

Fortunatelly whole unchrushed flax seeds are also available (as
natural laxative) that I grind just before consuming. How nice to know
that it is possible to get around this so called "omega3 shortage"
craze that is starting to take momentum.

What I would like to know is how much omega3 is lost by exposure to
light, in numbers like "loss of omega3 is x% per hour under store
shelf lighting".

Also of interest would be information like "loss of omega3 is y% per
minute under low temperature pan frying  conditions, and z% per minute
under high temperature pan frying conditions".

Does anyone have any data on omega3 loss due to light and temperature?

regards
andrew vecsey