Freeze-dried food and emergency rations: when they are worth it

What freeze-drying actually is

Freeze-drying removes water by freezing food and drawing off the ice under vacuum. The result is very light, keeps flavour and nutrients reasonably well and, correctly packed, can last many years according to the manufacturer. The trade-off is rehydration: usually hot water and several minutes of waiting.

It is not the same as conventional dehydration, which is cheaper, slightly heavier and does not keep as long.

When it is worth it

For a go bag, freeze-dried meals are hard to beat on weight and volume. For a 72-hour home supply they are usually unnecessary, because tins, cooked pulses, nuts and crackers cost far less and need no water or cooking.

• Go bag: freeze-dried meals or energy bars.
• Home for 72 hours: tinned food you can eat cold.
• Longer or isolated situations: a mix of both.

Water is the limiting factor

Freeze-dried menus add water consumption exactly when water may be scarce. Add that amount to your stored water calculation and keep a way to heat water without mains electricity, always used in a ventilated space and never with barbecues or generators indoors.

Storage and rotation

Keep packs somewhere cool, dry and dark, away from heat sources, and respect the manufacturer's dates. Write the purchase date on the pouch and review stock twice a year.

Try at least one meal of each type before buying a case: under stress, food people dislike simply goes uneaten, especially by children.