Food Spoilage

Since the foods we eat are all derived from living matter, they are all subject to the natural process of decomposition. Food not only decomposes, but is lost or spoiled by being consumed by other creatures than humans - rats, mice, flies, and microorganisms. Spoilage is characterized by a decline in eating quality, resulting in food that is less acceptable to the consumer in appearance, taste, texture or odor. In addition, spoiled food may not be safe for consumption. However, in contrast to food contamination, which is frequently not detectable and therefore a serious hazard in causing foodborne illnesses, food spoilage is obvious and detectable, and can more easily be prevented or avoided.

Foods may be classified as perishable, semiperishable, or non perishable, depending on how susceptible they are to spoiling. The most perishable foods are those with large concentrations of protein and/or water, which accelerate the microbial and chemical processes of decomposition. For example, fish, seafood, meat, eggs, and dairy products, which all have a high protein and water content, are very perishable. Watery fruits and vegetables such as tomatoes, peaches, berries, and leafy vegetables are also highly perishable. Semi-perishable foods contain less water and include those, such as potatoes, carrots, beets, turnips, onions, and apples, that can keep for several days or even months under proper conditions. Processed nuts, cereals, dried tea leaves, pastas, and dried beans and peas are classified as nonperishable because they contain very little water and will keep for months with little loss of quality.