All About the Flameless Ration Heater

Do you ever wonder how military forces eat meals when they are on the border or on far-off postings? Some of you might have heard of ready-to-eat meals that are liquid or wet in nature and available in small packets. They are also packaged in tins and small cans. Basically, the food needs to be stored in packages that are easy to carry and are compact. After all, you can’t expect army members to carry a huge bulk of food wherever they go, can you?

However, the question still remains, how do these packets, which contain wet food, get converted to edible food? You might be surprised that these packets of food have all kinds of items in them, ranging from entrée to main courses like rice as well as dessert! To convert them into food, you require the flameless ration heater.

What Is a Flameless Ration Heater?

A flameless ration heater is a tool that is used to convert ready-made food into proper meals. While the packets only contain wet items, when you heat them up, they transform into proper and satiating meals.

A flameless ration heater is self-contained in nature. You need to pour water into the heater to activate its exothermic properties, which then help heat up the food and make it edible. This is because the ready-to-eat meals usually require the food to be heated to a certain degree. For instance, a 226.8-gram packet containing an entrée might need to be heated to a temperature of 56 degree Celsius. This can easily be achieved by a flameless ration heater in less than 12 minutes.

As the name suggests, this occurs without the need for fire. The heating mechanism of the FRH is enough to deliver heated ready-to-eat meals.

How Does It Work?

The mechanics of a flameless ration heater are not hard to understand. You might think that the only way of cooking food is by lighting a fire. This product proves otherwise and uses heat to do the task. How this heat is generated by mere water is the main question posed by observers.

The heater makes use of the electron-transfer process to generate the required heat. This process is also called an oxidation-reduction reaction. This heater uses a fine powder of magnesium, which is mixed with iron and table salt. When you add water to the heater, magnesium reacts with the water and the water starts to heat up to the boiling point. Since this mechanism is occurring close to the food, the food is heated up in the process.

Details of the Oxidation-Reduction Process

Did you know that water can be used to oxidize magnesium metal? The effect magnesium has on water is similar to the reaction caused when iron metal is exposed to oxygen. The latter process is well known as rusting and is a type of oxidation procedure as well.

The reaction between the magnesium metal and water is quite slow and does not produce enough heat to make any difference. This is why a flameless ration heater makes use of table salt and magnesium in powdered form.

When finely powdered magnesium is mixed with table salt, the oxidation-reduction process is greatly enhanced. The salt water acts as an electrolyte for the iron and magnesium elements. It allows them to transform into a galvanic cell. Hence, each iron and magnesium particle start acting like small batteries. This means that at any time, there are thousands of such batteries in the flameless ration heater. The short circuit formed by these batteries are burned out quickly, which generates heat.

Why Bother with a Flameless Ration Heater?

The flameless ration heater continues to be one of the most used tools by the military to heat up food. There are even various commoners who make use of the product. Why would they do so? Here are a few benefits of using a flameless ration heater and ready-to-eat meals that come with it.


If you hate cooking and consider yourself to be a lazy soul, you can make use of this heater to soothe your hunger without making much effort whatsoever. All you need to do is pour water, and your job is done! Additionally, the product doesn’t really demand much. It is very easy to use and only needs a few tablespoons of water. This means that the process is not only quick but also very convenient and budget-friendly.

Perfect for Camping Trips

Are you sending your children on a camping trip? While food is generally taken care of, you can provide your kids with the ultimate experience through MREs and a flameless ration heater. It isn’t uncommon for campers to cook their food on open fire, but you will agree that is quite a dangerous way to satiate your hunger in the wilderness. Also, some places don’t allow you to light an open fire. This is where a flameless ration heater will come in handy. Since it doesn’t produce any flames, it ensures the safety of your child.

A Backup Plan for Disasters

You should always be ready for the worst-case scenarios. A natural disaster can occur anywhere and anytime. Equipping yourself with MREs with flameless ration heaters can ensure you have enough food to survive before rescue missions can help you out. Similarly, if prolonged outages of power occur, rendering you incapable of using your electric stove, this can be an excellent backup plan.

Emergency Food

Have you ever had your vehicle break down in the most inconvenient of places? Being stranded on deserted roads or getting blocked in due to harsh weather is the worst nightmare for many. Keeping an FRH and MRE along with a bottle of water can save you from hunger and starvation in such cases. Hence, you might want to equip yourself with it for the bad days.

How to Use a Flameless Ration Heater

The process of using a flameless ration heater is quite easy. This is what makes the idea so popular among military folks and commoners alike. Here are the steps you should follow when using a flameless ration heater.

  1. The heating bag will be sealed on the top. Tear this part off.
  2. Put your MRE food or container in the bag.
  3. You will be provided with instructions which will tell you how much water to pour into the bag. Generally, a few tablespoons of water are enough to do the trick. Basically, you have to pour water until you reach the marked waterline on the bag.
  4. Allow for the chemicals in the bag to dissolve. To do so, hold the bag for a while with the top open.
  5. Once the chemicals have dissolved or a few minutes have passed, fold the top part to close the bag.
  6. You must make sure that the bag stands upright in a slightly inclined position. Hence, use a sturdy material to give support to the product.
  7. Let it be for 15 minutes.
  8. After that time has elapsed, open the bag. You will find that your food is hot and can be served.

Stay Safe!

Just because there are no flames involved doesn’t mean you should handle the flameless ration heater and the food that comes out of it very lightly. You never know how hot the bag and food can be. Therefore, exercise caution when removing the food from the bag.

It is also common for premature reactions to occur when the product is stored. This is why you must ensure that you store the flameless ration heater in a place that is devoid of nails or any sharp items. This makes sure that the bag does not puncture.

Additionally, since the flameless ration heater works with water, you must keep it away from water and moisture to avoid premature reactions. If there is a lot of humidity in the air, there is a chance that the bag is coated with a magnesium hydroxide layer. This compound is not soluble and can hamper the flameless ration heater’s ability to generate heat when the time comes.

Choose the Flameless Ration Heater Carefully

You will find a few companies delivering flameless ration heaters and MREs. Don’t choose any one without thinking. Research about the company and learn whether the product works well or not. This is because every heater may not necessarily succeed in transforming food as per the requirement. Just like in any purchase, the quality of the flameless ration heater you invest in matters.

If you are a camper, a hiker or an individual who likes having a backup plan, make sure you get yourself a flameless ration heater. However, don’t expect the food to be as good as the one you make on the stove. That doesn’t mean it won’t be tasty. Some MREs are really good. It all depends on what your taste buds like. Try them to find out. Use a flameless ration heater to heat them first, though.

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