This my dehydrator from Westphalia (http://www2.westfalia.net/shops/household/kitchen/cooking_desiccating_grilling/desiccating_appliances/193811-food_dehydrator.htm.)
It has 5 trays to hold the food, a top which includes the 'hairdryer' that provides the hot air which passes down the middle 'hole' and rises back up past the food. As the trays are slotted (it's really designed for dehydrating fruit) I have to use 'baking paper' while the food is wet
The basic idea is the same whatever you pay: you put in 'wet' food, the machine circulates warm air around it removing all the water. When it's done its work you end up with a dehydrated version of what you put in - at roughly 50% of the weight.
This means you can carry far more food for a given weight - a tasty healthy & substantial evening meal can be packed at 150-200 grammes.
To enjoy the food you simply add the required amount of boiling water, let it absorb and then you have fantastic food miles away from home which tastes like it's just come out of your kitchen.
How to dehydrate your food
- Cook your food at home, allow to cool
- Weigh a portion of the food in its wet form (ideally stick to standard weights eg 300 gm)
- Prepare your dehydrator for the food you're going to add - if you bought a cheap one designed for fruit slices then you need to use baking paper or paper plates to hold the food in place in the machine.
- Dehydrate your food, this can take upto 12 hours, check it regularly and be sure to break up and clumps of food.
- Get a supply of 'A5' sized zip-lock bags, most supermarkets sell them, you want them to be just big enough for one portion.
- When the food is completely dry place it in a bag and weigh it again. The difference in the weight is the amount of water that's been removed - 100gm = 100ml of water (apparently this also works in proper UK ounces/ fluid ounces but not US ones).
- Write a description of the food and the water required to rehydrate on the bag and seal the bag.
- Place the bagged food in the freezer until you need it, it'll last for months in there.
- Once out of the freezer your food will stay in perfect condition in your rucksack for at least a week as long as it is kept completely dry.
- You need a cozy to keep your food warm while it rehydrates. Some people use a fleece jacket or hat but I assume I'll need them as a jacket or hat and prefer a dedicated cozy. These are made from insulating material so allow your food to rehydrate while retaining heat. There are instructions for cozy construction elsewhere on this blog.
- I use two cozies, a small one and a large one, hopefully the logic of this will become clear. Place the bag of dehydrated food in the small cozy adding the required amount of boiling water. Squeeze out any excess air and seal the bag. Place the small cosy in the larger one.
- After about 20 minutes (you need to experiment for each dish to find the exact time required) remove the small cosy, open the bag and using the small cozy to protect your hands eat the meal from the heat.
- Using this method you can have good value, preservative-free, tasty food exactly as you like it with the minimum of in-camp hassle and no dirty pans or plates to wash up.
- Be sure to dispose of empty bags responsibly