Dehydration
Dehydration of food products destroys the enzymes present and inhibits the production of bacteria and fungi. Dehydration functions by decreasing the amount of water molecules in a food product to a point at which microorganisms are unable to grow. The absence of free moisture in the food product removes detrimental microorganisms as such bodies require free water molecules to expand and multiply. Furthermore, the absence of water prevents several enzymatic and non-enzymatic reactions from occurring. Dehydration, on Arda, would be performed through placing the food product in an area where it would come in contact with prolonged solar heat. (see fig2) Alternative methods of dehydration include salting and sugaring where the addition of salt or sugar molecules binds to the free water molecules in a food product. As a result, the concentration of free water molecules decreases within a food product and this directly decreases the amount of free water molecules available for bacterial growth. Low temperature boiling of a food also serves to decrease the amount of free water molecules by evaporating the water molecules.
Figure 3: Fish preserved through dehydration by salting
Raw Materials:
The raw materials needed for food preservation are the food products themselves. Due to the large variety of food products which are able to be preserved, the broad categories of food shall be written of. The fundamental categories of food consist of fruits, vegetables, and meats. Fruit and vegetables are obtained through harvesting such foods when they are mature. Meats are obtained through slaughtering an animal in terms of poultry, beef, and pork. Fish are obtained through catching them in their aquatic habitat.
Fig 4: A basket used to dehydrate foods through solar heat
The raw materials used as additives in preservation include salt, sugar, vinegar, and formaldehyde. Salt (sodium chloride, NaCl) is obtained through the evaporation of brine from salt beds, sea water, and mining. Salt is found in a small crystal form due to its ionic structure. Sugar, a compound of hydrogen, carbon, and oxygen, is found in several forms but the most common is that of glucose (C6H12O6). Lactose, found in dairy, and fructose, found in fruit, are other forms of sugar which are used when preserving food through inducing fermentation at a more rapid rate. Sugar is present in the food products being preserved and thus does not need to be harvested from an exterior source. Vinegar (acetic acid, CH3COOH) is used as the solution in which pickling occurs. Vinegar is produced through a two-fold process of fermentation. The initial process of fermentation consists of yeast converting sugar into alcohol (alcoholic fermentation). The bacteria of the genus Acetobacter in turn convert the alcohol into acetic acid (acid fermentation). Formaldehyde (CH20) is used in smoking food products and is produced through the gaseous particles in the smoke of burning wood.
alcoholic fermentation
enzymes
Glucose ---------------> carbon dioxide (CO2) + ethanol (EtOH)
+ energy (a gas)
acid
fermentation
C2H4O2 + H2SO4 —————> 2 CO2 + 2 H2O + H2S