Freeze-dried food, when the weight of the backpack is a problem


Álex Pérez Caballero
– Monday, April 30, 2018 – Updated at 09: 00h.

In some outdoor activities the weight of food
 it is carried to the extreme extreme. In a sporting challenge like the Marathon des
Sables, for example, you have to carry all the food that is
will consume in the six days of this race in stages. The water
It brings the organization but the food is on you.

What is a lyophilisate?

Freeze-drying is a process by which removes all water from food without losing its nutritional qualities ,
 or almost: minerals, proteins, fats, etcetera. If we consider
that the meat has around eighty percent of water, that the
percentage in an apple is eighty-six percent and that even
 dry pasta is a ten percent liquid element, it's easy
suppose that eliminating or reducing that water means decreasing the weight of
food and, what is also very important, lengthen the time of
conservation, because the bacterial action and other biological processes
that deteriorate food depend a lot on the concentration of water
what they contain

This is not something new: since time immemorial, man has dried naturally
 fish, meat, seeds and fruit to conserve and consume them in
the months without production or shortage, or to use it in migrations
 or on exploration trips. Beans, chickpeas and lentils are a
 clear example of dry foods of vegetable origin. The jerky and the
Mojama are of animal origin.

Thus, lyophilization is nothing other than a desiccation "on the gross" ,
 fast and forceful, which is done by industrial means. The process
consists of freezing a food very quickly, and then, in
special conditions of pressure and temperature, proceed to a
very rapid sublimation of your water. Sublimate, as we will remember from
our chemistry classes of the institute, is to directly pass a
element in solid state to gaseous state, in this case, of ice to
steam, without the water passing through the liquid phase, as would be normal.
This process is known as dehydration, and is achieved in a
natural (sun and wind) or by special ovens and appliances that
They can easily buy. The lyophilization, being faster, allows
that the entrainment of nutrients that occurs in a dehydration
conventionally produced, preserves practically all the flavor of
 the food and hardly disadvantages its natural texture to be
rehydrated.

Freeze-drying, being faster, the drag of nutrients that occurs in a dehydration
conventional barely produced

Freeze-dried foods offer a crunchy texture ,
 while dehydrated ones have a softer texture or
flexible. Regarding conservation, being in both cases speaking
of properly packaged products, dehydrated products are usually
retain their qualities for about a year, while
lyophilized can be stored and stored for a longer period,
provided that the container is kept hermetically sealed so that it does not
absorb moisture.

On a daily basis

Today
in day the lyophilized are part of daily life and we do not even give ourselves
account. In any supermarket you can find many preparations
foods that have resorted to lyophilization. Maybe the most
clear that of coffee, tea and extracts of soluble malted cereals.
 We all know that you only have to add hot or cold water to use them.

Or the succulent mashed potato and the sopinstant, or the more and more
abundant Yatekomo and the like that contain dehydrated pasta and
freeze-dried preparations of vegetables and meat (arrival at
Spanish supermarkets in the eighties of the last century of
the "bolinos", some plastic cups that contained pasta, mashed
potato and other foods and in which you only had to add water
hot to prepare them, it was a real revolution in the
mountain feeding, based until then on the sausage and the tin
of fabada).

Preserves practically all the flavor of
 the food and hardly disadvantages its natural texture to be
rehydrated.

We will also find fruits and vegetables for your
direct consumption as snacks or to prepare cooked dishes and
salads: strawberries, red fruits, pumpkin, potato, beet, apple,
tomato, yucca, banana …

Apart from the aforementioned products,
There are other more elaborate food preparations for sports use.
 In the field of mountain and maritime navigation, it has been a long time since
some envelopes are used that are filled with hot water and, after
a few minutes, they are reconstructed normally with the shape of puree or cream ,
 that resembles very much what could be a conventional dish.

With
one hundred grams of product and adding 350 milliliters of water, we obtain
about 450 grams of reconstructed food. We can find dishes Los
freeze-dried foods are first frozen at very low temperature and
then they heat up quickly. as many as taboulé with
vegetables, chicken with rice, pasta with tomato, goulash, risotto, paella …
Of course, lyophilisates can be a good solution for
Enjoy our long-distance adventures to the full without being left
crushed by the weight of the food.

Food of astronauts

Although
 It seems a very modern process, natural lyophilization exists from
the antiquity. In the Andes, the Incas allowed food to
freeze during the night and then leave them in the sun. The strong
radiation at high altitude and low atmospheric pressure caused the
sublimation of the water that had frozen. Freeze drying applied to
 food was greatly favored by the space race,
especially with the long stays in the orbital stations,
 you had to get the astronauts to eat well and
balanced but minimizing the weight of the food that
had to be transported to space.

                

How to start traveling by bicycle

                                

Traveling by bike

Practical baggage bicycle touring manual

by Alicia Urrea; Álvaro Martín

This manual is designed to explain what you should take into account to start traveling by bicycle. Includes all kinds of information to plan your first route. From how to design your route, things to take into account depending on the different travel companions, how to choose or prepare the bike, going through the type of equipment needed. Finally, the last part of the manual is dedicated to the day-to-day of the route: days of heat, cold or wind, route feeding or how to find a place to sleep.

                                



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