Fermented Food Lab Report

Fermented foods are made by the partial oxidation of sugars, or sometimes other organic molecules, in a food product. The difference between this and the normal cellular respiration is that the electron donor from the electron transport chain is an organic compound rather than oxygen. One challenge for producing fermented foods is the pH levels of the food. Bacteria have different optimal pH levels. Therefore, as pH changes due to fermentation different bacteria will begin to ferment the food. For example, during the fermentation of sauerkraut the pH drops as acid accumulates in the food and the bacteria used for fermentation changes from heterofermentative bacteria to homofermentators. When heterofermentators are active, the acid levels are typically increased to about 1% and then homofermentators take over and increase the acid levels even more up to about 2%.
Since the fermentation process is dependent on sugar, once sugar levels are depleted the food product can no longer be fermented any further. For example, a food like grapes can have higher fermentation yields because they have high amounts of sugar naturally. Whereas a food like coffee beans have much less sugar and therefore will not be able to produce fewer products of fermentation. In conclusion, one of the many challenges of fermentation is monitoring pH levels to ensure that the right process of fermentation is taking place. A limitation of fermentation is the amount of sugars available in the food product being fermented because sugars are necessary for all fermentation