What ever you decide to do DO NOT put the cans or tins directly on the Esbit Stove or other flame-based stoves. That includes alcohol stoves.
We had a familiarization course when we did wargames with NATO and in one of the classes this wonk from DFSC told us that the tins in European rations - and some trays - have their insides coated with a film to protect the metal from food acids and if you apply flame to the outside of them, it literally leaches the film into the food.
"We" were heating rations straight on ESBIT stoves for decades and in basic training any soldier get taught how to cook a ration on an ESBIT stove.
Me on a winter training back in the 80s
After sleeping, we got up for "breakfast", heating an EPa entree (my buddy was gross, he ate entrees for breakfast
RECNEF wrote:So basically when we consumed the Italian rations we decanted them into our mess tins and cooked them that way... Just saying, Cancer sucks. Kidneys are necessary for things like drinking beer. Want to be careful with that then, right?
Italian and some other rations (French, Dutch etc.) made from regular off the shelf canned food. They are made for civilian use and you are right, their cans have an "isolation layer". But especially German EPa entrees were designed to be "cooked" on open fire and the square shaped containers didn´t have that isolation. We added some margarine that came with the EPas to prevent the food from scorching and cooked/fried it right on the ESBIT stove.
Current containers have changed. Once you heat them too long/hot in boiling water, you can "cook off" that "plastic layer" off the container.
I still "cook" EPas on an ESBIT stove without hesitation and also any other can of any other ration.
Last "winter" we (reserve unit friends) did a little "mechanized hike":
1992 EPa - 24 years "old"