Fermentation is one way of preserving and adding flavour to food. It is a process used all over the world. The three main types of microorganisms responsible for developing fermentation in food are bacteria, yeast and moulds. What comes out of the process has usually been worked on by a combination of microorganisms. The health and taste of the end product depends on how well unwanted microorganisms are controlled.
Cheese is a familiar fermented food. The taste of cheese can come from the rennet, which helps curdle the cheese, a specific live culture used to start fermentation, and the surrounding environment. Some common bacteria found in cheese include a number of combinations involving bacteria from the Streptococcus and Lactobacillus family. Other live cultures like mould can develop during the ageing process to change the flavour of the cheese, many of these come from the Penicillium family.
Another dairy product of lactic acid forming bacteria is yoghurt. Two microorganisms responsible for the fermentation process may be Streptococcus thermophilus and Lactobacillus acidophilus or Lactobacillus Bulgaricus.
Vegetables and Fruits
Environment is a way to control what types of bacteria are present during fermentation. Many vegetables are pickled through the use of bacteria that can live in salty conditions. Like cheeses, the bacteria present produces lactic acid. Sauerkraut made with cabbage and salt water is one of them. Depending on the environment, the fermenting cabbage will contain Leuconostoc mesenteroides and Lactobacillius planterum. Other familiar pickled vegetables include cucumbers and beetroots. Some pickled fruits include chutneys like mango. There are condiments such as ketchup, soy sauce and mustard that can be made with fermented products.
Another familiar food that has a fermentation process in its production is cocoa. The bean is fermented for a few days after harvesting to produce a better flavour. This also helps stop the germination of the seed. Eventually, the bean is dried and ground.
Bread is a product of fermented yeast. The yeast feeds on sugars. One of the by products is carbon dioxide which is responsible for making the dough rise. It also gives the bread its flavour. Like with the bacteria and moulds, yeast comes in both beneficial and detrimental forms. Most bread dough contains yeasts in the Saccharomyces category like Saccharomyces cerevisiae. Doughnuts, pizza and other pastries also contain yeast. Another common yeast product is alcohol.