Cool water.

When using self-heating food, cold water should be used to react with the self-heating bag. If hot or boiling water is added, the reaction may be too fast, causing the self-heating bag to expand violently or even rupture.

Self-heating food has a heating pack, which will rise in temperature when it encounters water. The heating pack is mainly composed of iron powder, aluminum powder, coke, activated carbon, quicklime and other materials. Adding cold water to react, the temperature can reach 150°C, the steam temperature can reach 200°C, and the longest heat preservation time can be maintained for three hours. If an accident occurs, it can easily cause burns and other hazards.

Special tips for eating self-heating food

1. Be careful not to let the hot water flow out during use. Turn it over every 3-5 minutes to heat evenly and be careful of steam burns. Because the temperature can reach about 98 degrees Celsius when heated.

2. Put the reacted heating device into an insulating paper bucket to make two heating devices for body warming. Fold the mouth well to release heat for 2.8-3 hours.