Fermentation questions…?

A major ability of food preservation by way of fermentation is the lowering of pH. An increase in acid production and a lowering of basic elements fermantation substrates results in a lower pH. Many food spoilage microoganisms do not or cannot thrive in this environment. Other considerations when applicable include alcohol, decreased oxygen, and a decrease in a nutrient source.
The amount of alcohol that yeast produces in making bread is negligable and not worth considering. But what very small amount it does produce is distilled during baking. So little that both Jews and Muslims can consume it.
http://qa.sunnipath.com/issue_view.asp?id=14374&hd=1&cate=0&t=rss
[wiki]
The primary benefit of fermentation is the conversion of sugars and other carbohydrates, e.g., converting juice into wine, grains into beer, carbohydrates into carbon dioxide to leaven bread, and sugars in vegetables into preservative organic acids.

Food fermentation has been said to serve five main purposes:

enrichment of the diet through development of a diversity of flavors, aromas, and textures in food substrates.
preservation of substantial amounts of food through lactic acid, alcohol, acetic acid and alkaline fermentations.
biological enrichment of food substrates with protein, essential amino acids, essential fatty acids, and vitamins.
detoxification during food-fermentation processing.
a decrease in cooking times and fuel requirements.

Fermentation has some uses exclusive to foods. Fermentation can produce important nutrients or eliminate antinutrients. Food can be preserved by fermentation, since fermentation uses up food energy and can make conditions unsuitable for undesirable microorganisms. For example, in pickling the acid produced by the dominant bacteria inhibit the growth of all other microorganisms. Depending on the type of fermentation, some products (e.g., fusel alcohol) can be harmful to people’s health.

Alaska, despite its small population, has witnessed a steady increase of cases of botulism since 1985. It has more cases of botulism than anywhere else in the United States of America.[9] This is caused by the traditional Eskimo practice of allowing animal products such as whole fish, fish heads, walrus, sea lion and whale flippers, beaver tails, seal oil, birds, etc., to ferment for an extended period of time before being consumed. The risk is exacerbated when a plastic container is used for this purpose instead of the old-fashioned method, a grass-lined hole, as the botulinum bacteria thrive in the anaerobic conditions created by the plastic.