Microbes and Food Relationship

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Microbes and food have always had a love-hate relationship. Food producers have learned to harness their power -- and sometimes for good use. There is no doubt that organically grown fruits and vegetables are superior in flavor. Now, despite arguments to the contrary made by food manufacturers, they may well be more nutritious for a variety of reasons. There are always studies available to prove any point, especially one where chemically doused foods are more nutritious. But then, like bacteria in the throes of death, food manufacturers mount a valiant effort in trying to convince those near-at-hand that what they say is valid. But, be that as it may, the choice is ultimately made individually. Bacteria are, to a great extent, resistant to the effects of irradiation because of their ability to repair their damaged DNA. Sometimes, however, their repair is faulty, and the new DNA becomes abnormal, causing a new strain. Salmonella and Campylobacter are easily removed by irridation, but other bacteria are more stubborn. Some, like Clostridium botulinum and L. monocytogenes, have the ability to survive the drying techniques of irridation by converting themselves into tough, little spheres.

Food irradiation, however, exposes an edible product to the equivalent of two and a half million chest X-rays. How many nutrients are left after this bombardment is anyone's guess, but, at least, most of the germs are gone. Most, not all. Short term studies have shown the destruction of numerous vitamins through this process as well as the formation of new carcinogens. There is also the possible formation of mutant bacteria and viruses. Since the USDA approved such a process in February of 2000, fast food chains, restaurants, school lunch programs, and cafeterias are now using irradiated meat products without the public knowledge. The most common usage for bacteria in food preparation is with dairy fermentations. Yogurt and cheeses have been made for centuries using bacteria. The ancients may not have known exactly what kind of bacteria that was needed or if what was needed was, indeed, bacteria. All they knew was that the previous batch was required to make a new one. Many people lack the ability to break down and absorb lactose, the sugar molecule in milk. As a result, it enters the gut, producing acid and gas, causing pain and diarrhea. Fermented milk products metabolize lactose into lactic acid, which is more tolerable for many people. The most common fermented milk product is yogurt. The lactobacilli used in the making of many yogurts, however, may not be the same type as found within the common flora of humans as there are many different strains. The following are some of the bacteria used in the diary industry: * Acidophilus milk is made with Lactobacillus acidophilus.
* Butter is made from pasteurized cream, to which a lactic acid starter has been added. The starter contains, for example, Streptococcus cremoris or S. lactis, but requires Lactobacillus diacetylactis to give it its characteristic flavor and odor. * Cheese is often made with Streptococcus and Lactobacillus bacteria. Fermentation lowers the pH, thus helping in the initial coagulation of the milk protein, as well as giving characteristic flavors. In such Swiss cheeses as Emmentaler and Gruyere, the typical flavor is the result of the use of Propionibacterium. Cheese can be classified within two groups -- ripened and unripened. Unripened cheeses consist of cottage cheese, cream cheese, and Mozzarella, for example. These are soft cheeses and are made by the lactic acid fermentation of milk. Many different bacteria are used to produce the various cheeses, but Lactococcus lactis and Leuconostoc cremoris are used most often. Soft cheeses can take one to five months to ripen; hard cheeses, three months to a year or more; and very hard...
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