Most, if not all, fresh, natural foods without any form of processing contain the highest level of nutrients and have the best flavor and texture. The reason why fresh foods are perishable in a relatively shorter time compared to processed foods, is due to the active presence of microorganisms such as fungi, yeasts, bacteria and their enzymes. Enzymatic activities promote chemical reactions within food tissues, and this contributes to the deterioration of food quality. A simple explanation would be that chemical reactions resulted in by-products, since the harvested and slaughtered food is no longer alive, these by-products could not be metabolized or removed from the tissues and accumulate, over time, rot and damage these tissues.

The only benefit I can think of from preserved and processed foods is that they generally tend to have a longer shelf life. However, preserving food usually involves loading it with unhealthy amounts of additives and chemicals. If these additives, like salt and sugar, could be eliminated from our bodies through the kidneys and the liver, these compounds will load the workload of our organs. However, if the compounds tend to accumulate within our body, the effect would be detrimental to our health and could possibly be fatal in the long term. Furthermore, exposure of fresh foods to heat, light, alkaline or acidic condition, cellular damage from chopping and cutting, lead to denaturation, oxidation and destruction of proteins, vitamins and minerals.

One of the safest ways to preserve food without the introduction of any additive is by freezing. Almost all types of food can be frozen. USDA reports have shown that freezing does not destroy nutrients in food. However, depending on the type of food, a loss of flavor, texture and color is expected when the food is frozen. Also, food is best frozen fresh, before its nutrients begin to degenerate over time. Therefore, freezing food just before it spoils, in fact, will not help preserve its nutritional value. Microorganisms like bacteria would be inactivated, but would not be destroyed, when frozen, so food will no longer spoil or deteriorate. However, once the food is thawed, the activities of the microorganisms continue and the food must be handled as we would with fresh food, to ensure its safety for consumption.

Another safe food preservation alternative is by drying. Drying is usually done by heating and removing moisture from food, and it is easier to dry plant-based products than animal-based products. In addition, drying of animal products generally involves the addition of salt. Nutrient loss is primarily due to heat, rather than moisture loss. Also, more nutrients are lost as food is processed prior to the drying process. Most importantly, dry food must be kept dry at all times to preserve its quality. Introducing moisture into dry foods will lead to mold, since mold spores are virtually ubiquitous. To be sure, moldy foods should be completely discarded. Mold forms deep roots in food tissues, therefore cleaning or cutting visible moldy parts will not guarantee that food is mold free. Drying food will correspondingly concentrate the nutrient content, therefore the nutrition level of dry food is much higher compared to a similar weight of fresh, moisture-filled food. However, the content of sugar, salt and fat is also higher in dry foods, something that we must take into account during food preparation,

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How to preserve food safely