The problems with conventional refridgeration.
One issue with refrigeration is the degradation of flavor, aroma, and texture as a consequence of exposing fresh produce to temperatures below forty-five degrees fahrenheit. For example, the tomato, the potato, and the onion are often refrigerated to their detriment.
Specifically, certain enzymes and fatty acids that are found in tomatoes and contribute to their aroma and flavor will degrade with low temperatures and cause these flavors to disappear permanently.
Furthermore, the membranes in the cell walls are compromised giving the tomato a watery mealy texture. Onions go through a similar process and refrigerators makes them soft and unappealing. Some vegetables, like the potato, contain starch, which turns to water when refrigerated, making the potatoes taste unpleasantly sweet. This also causes visible premature darkening. One food whose appropriate place is often debated is bread. Bread undergoes a transformation causing linear molecules rearrange themselves into crystalline structure. This process is called gelification and causes the bread to get stale by expelling water from the polymer network. Temperatures between forty-five and negative fifteen degrees fahrenheit speed the staling drastically. On the other hand bread is susceptible to mold, making the refrigerator and stale bread appealing.
Air moisture can becomes an issue at reduced temperatures. When the air is cooled it reaches its dew point and starts condensing onto surfaces. This condensation can lead to freezer burn or accelerate fresh produce spoilage.
Aside from directly negatively affecting certain foods, refrigeration also does little to prevent oxidation and in some cases actually accelerates these processes. Lipid oxidation can cause oxidative browning and off flavors of fatty foods, especially cooked foods like fried chicken, roast beef, or salami. For example, cheese oxidation is accelerated by cold temperatures. In this process the fat and carotene oxidize and lead to bleached areas and a tallowy flavor.
Oxidizing enzymes are present in many foods. Oxidizing enzymes, like catalase and peroxidase, cause vegetables to brown. Another common example of oxidation is the deterioration of flavor in pre-ground spices vs freshy ground spices.
Conventional refrigeration does little to reduce wine and beverage oxidation; after a bottle is opened it may be recorked, however, the internal atmosphere is compromised.
Refrigeration is also simply not appropriate for many foods that could benefit from preservation. Foods like flour or corn starch, which are susceptible to pests such as mealworm, and are often affected by changes in air humidity, do not benefit from refrigeration. Oxygen also speeds the deterioration of vitamins in food, which are quick to oxidize and decompose.