Weight
is the principal limiting factor in this type of expedition. In the
106 kg loaded onto each sledge, the 100 days' food supplies represent
60% of the total.
It was with this in mind that everything had to be put in place
to ensure maximum nutritional value for a minimum weight, whilst
using packaging which would match up to strict loading criteria
and its ability to be naturally recycled.
Freeze Drying
Freeze drying (cryodessication) combines the virtues of dehydration
and chilling for preserving. The fresh product is first of all frozen
to a low temperature (- 40°C); put under vacuum it is then progressively
reheated in a way which provokes conversion of the ice. This technique
presents the huge advantage of enabling the product to keep its
flavour, its basic properties and all its biological value.
Retaining water in food is a problem for the weight factor. In
the case of this expedition, the use of cryodessication as an industrial
process has allowed a saving of about 10 kg on the total weight
of foods which need to be transported. These operations were carried
out by the specialist laboratory at the Centre for Rural Economics
(CRE) of Marloie at Marche en Famenne.
Packaging
The study on packaging of the food rations for the expedition was
led by the Ecole Supérieure d'Ingénieurs en Emballage
et Conditionnement (ESIEC) of Rheims (Higher Engineering Institute
of Packaging and Packing). The objective followed was to optimise
the total packaging weight whilst guaranteeing food preservation
and sturdiness. Before being split into daily rations, the different
components were packed in a thermo-retractable film of 25 microns
thickness; formed from 3 co-extruded layers of polyolefine, which
is entirely recyclable and can withstand extreme conditions. The
industrial processing was carried out by a company specialised in
special films and packaging, Bolore Technologies in Quimper, France.
The total weight of packaging was thus reduced to 14 grams per ration,
or 1.4 kilos for the 100 days of food.
The splitting up of the anhydrous milk-fats (AMF).
The CORMAN company sited at Goé-Limbourg, between Verviers
and Eupen, produces almost 80,000 tons of anhydrous milk-fats (AMF)
and specialist butters (reduced fat and others) per year.
Splitting the fat content of milk enables the hardness of the
AMF to be modified. The splitting of fat matter is a physical process
of division of the fat into its various components. It is the only
modification treatment of the physical properties carried out on
milk fats. The operation is based on crystallisation, which takes
place in tanks where the fat matter undergoes a programmed chilling
whilst being stirred. The crystalline phase (stearic fraction) is
separated from the liquid phase (oleic fraction) by filtration.
The possibilities of splitting are more or less infinite. When applied
to the fat matter in milk which melts at 32°C, it is possible
to prepare fractions at the point of fusion and adjustable between
10 and 44°C.
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