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Germination of bacteria mean: the process resulting in the formation of a new mature vegetative bacteria from a spore following heat activation and slow cooling
Since bacterial organisms are so minute, it is impossible to view the organisms without compound microscope. In order to visualize the cellular components and to differentiate bacteria from other microbial agents, staining techniques are used by scientists to categorize different bacteria.
Gram staining is a special method that involves dying the outer covering of the bacterial cell wall that prevents it from physical and environmental trauma. On the basis of gram staining, bacteria are widely classified as gram positive (bacteria with the cell wall) and gram negative (bacteria without cell- wall).
There are a number of structural and functional variations in the bacteria of one group that helps in adapting these bacterial agents to survive in one environment where other bacteria cannot.
Vibrio cholerae is the causative agent of cholera and is associated with intake of improperly cooked food or poor sanitary conditions. Vibrio Cholerae is linked to hundreds and thousands of deaths worldwide (mostly in under- developed countries) due to cholera outbreak.
The most common causative agent of food poisoning throughout the world is Enteritis salmonella and can lead to serious and life threatening food poisoning, diarrhea, circulatory shock and dehydration in children. Infection can be controlled by timely intake of proper antibiotics and circulatory support.
Sorry, this is not my specialty
Aerobic and anaerobic bacterial endospores can be germinated if calcium chloride and dipicolinic acid are added to well-washed suspensions. Maximum germination is obtained when the calcium and acid are present in a molar ratio of one or more. This suggests that the1:1 chelate of calcium and dipicolinic acid is the agent that induces germination
There are some species of bacteria called as THERMOPHILES, these bacteria can survive temperature upto120 C. So if your cooking temperature is less than this temperature then these bacteria can survive. During cooking no bacteria can germinate as it is not a favorable condition for germination but the sopres survived during cooking can germinate in later stages.
We can destroy most pathogenic bacteria or reduce their number by simply cooking or reheating food above75OC, but remember spore forming bacteria and exotoxins can survive normal cooking processes.
The thermophilic bacteria may servive in very high temperature therefore heating up to121 C is recommended for autoclaving the laboratory tools to get the aseptic conditions.
Some food ingredients could not be heated to such high degree, then the thermophils are avoided by proper cooling of the food during storage period.
The examples to thermophilic bacteria in nature: Pyrococcus furiosus, Bacillus anthracis.
Clostridium botulinum spores are resistant to high temperatures. They can remain viable after boiling for hours. They are killed by exposure with a wet environment at120 C for30 minutes.
According to World Health Organization and some legislation, in cooking the following temperatures should be considered to prevent microbial growth:
1. Below +4 C
2. Above +65 C
3. Out of the danger zone or it should not be between +4 C and +65 C, or the rule of keep hot food hot and cold food cold.
During cooking there can be some specific thermophilic sporeforming bacteria that can resist high temperature. These bacteria can normally from Bacillus spp. But according to my experience most of the bacteria can be eliminated /stopped from growth in above55 C.
