One of Meal Kit Supply selling points is that the ration heater is 22 grams. In one of my earlier posts I said that "The water-activated flameless ration heater is not your standard heater either. It is a heavy duty 22 grams, instead of 11 grams, and will heat up your rations in the coldest of conditions." So, I set out to do an experiment because unlike most backpackers, my friends and I prefer to go outing in the worst of winter conditions.
The water, potato cheddar soup, and beef ravioli from menu 5 were placed in the refrigerator for two days to simulate a constant temperature of 38 degrees Fahrenheit. This helps to control the experiment parameters for future testing.
This is the dry component of the ration heater. The outside of the packet is tea bag material, and the powder is finely ground to increase it's surface area, ergo to increase the speed of the chemical reaction to water.
Notice that the ration heater is about the same size as the pouch, so that the heat is transferred more effeciently.
About an ounce of water was added to the ration heater, and the cold MRE pouches were placed around the heater package. I was surprised at how little water was needed for the heater. I did use a rubber band to hold the pouches closer to the heater, but the package recommends placing a weight on the top of it. I don't think it will make much of a difference. The heater package with the MREs were placed back into the refrigerator to simulate the cold environment. The bundle did its work for 10 minutes as recommended by the instructions.
After ten minutes in the refrigerator, the cheddar potato soup had reached 86 degrees Fahrenheit.
The beef raviolis reached a temperature of 70 degrees Fahrenheit. I wasn't really impressed with the result. Perhaps the thicker consistency of the beef raviolis had made a noticeable difference?
I was curious to how hot the ration heater could get, and at 208 degrees, it is just a few degrees shy of the boiling point of water. The cold beef raviolis were wrapped back in the ration heater, rubber banded, and placed back into the refrigerator.
After another 10 minutes, the final MRE was brought out of the refrigerator and the reading was 90 degrees Fahrenheit. The ration heater was slightly hotter than tepid, so I don't think that the beef raviolis were going to get any hotter.
As my first go around with the ration heaters, I can see ways to improve upon my effectiveness with them. This experiment was about the raw data without any modifications to the heating routine. In cold weather environments, I would try to keep the pouches close to the body to warm them to above the air temperature. I also should have taken into account that the chemical reaction of the heater would also be slower, and I should have lengthened the time from the recommended 10 minutes to about 15 minutes. My thinking is that the instructions are for average conditions, and this wasn't your average condition.
The ration heater contains finely powdered iron and magnesium metals, and table salt according to my research, and the added 11 grams is very much needed in cold weather conditions!
In the outdoors, I would also try to maximize my heat retention by placing the ration heater in a extra jacket, clean socks, or other piece of clothing. That way it could insulate the heater from the elements, and hopefully transfer more heat to the MREs.
Just like any other skill, the more practice at heating MREs with these, the hotter the final temperature can be achieved. The actual application or use is always superior to theories about such application or use.