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Food Storage Warm greetings to you, Today I would like to bring to you an article written by Marti Fry about the storage of foods from a "Life Science" point of view... I am sure that you will find it interesting. Does Freezing Harm Foods? We know for certain that heating foods (cooking) destroys foods by changing their chemical and organic structures. Proteins are coagulated (fused and hardened) and their amino-acid molecules are broken up, thus making them unusable. Carbohydrates become partially or wholly caramelised, though this is not readily detectable in the earlier stages of cooking. Caramelised sugars are indigestible, hence toxic to the body. Minerals are changed to their unusable and poisonous inorganic state and vitamins are largely , if not wholly ruined. The question arises whether the opposite extreme, freezing , likewise alters the chemical and organic structure of foods. Let’s pursue this method of food preservation. First, we should note that freezing does not affect foods of little water content : nuts, seeds, dried legumes, and dried fruits lose nothing by freezing. In nature, seeds and nuts remain fertile no matter how cold it gets. The more water a food contains, the more it is adversely affected by freezing. When a food is frozen, its water expands. This causes 2 immediately destructive occurrences; 1) the cell walls burst and the cell content are spilled due to the internal water expansion. Hence the cell’s life is lost. 2) Oxidation occurs where air reaches the frozen foodstuff; hence nutrients are lost. In addition to bursting the cell walls of food and thus allowing oxidation to occur, two other things happen. 1) When the cells burst, certain of their organelles release self-destruct enzymes called lysosomes. While these enzymes are not active during freezing ( and some are even destroyed) those which remain intact will speedily decompose the cell contents upon thawing. Lysosomes are in cells for the purpose of self-destructing dead cells so the dead cells will not create problems for the organism. 2) Whether oxidized or deranged by its own lysosomes, dead cells become soil for bacteria and fungi when the temperature becomes favourable again. Bacteria are active at just above freezing up to temperatures around 70 degrees C. Oxidation of burst cells is the foremost cause of food deterioration during frozen storage. Frozen foods never taste as good to an unperverted palate as their fresh counterpart, even if no additives and pre-freezing treatments are employed. This, of course is due to their deterioration while frozen. While microorganism such as bacteria are also inert during freezing, they become active just as soon as they are thawed. Hence, frozen foods, once removed from the freezer, decompose much quicker than do fresh foods. It is well to repeat that foods are rapidly destroyed when cell walls are burst, whether by freezing, cooking, blending, juicing or mashing. Oxidation occurs when cell contents are exposed to the air, and if temperatures are favourable, the cells own lysosomes self-destruct its components. Frozen foods should be used in moderation, they may be helpful in certain circumstances but they should not form part of our daily foods.