why wine and beer soured

How to prevent food spoilage

Soured because yeast convert the sugars to alcohol in the absence of air. But in presence of air bacteria changed alcohol to vinegar (acetic acid) - FERMENATION

Leads to the establishment of the relationship between disease and microbes

To overcome spoilage: Heat the beer and wine just enough to kill most bacteria - PASTEURIZATION

Used till today

is the process of heating to a specific temperature for a predefined length of time and then immediately cooling it after it is removed from the heat

The process slows spoilage caused by microbial growth in the food

1.The same Pathogene must be present in every case of disease

2.The Pathogen must be isolated from the diseased host and grown in pure culture

3. The pathogene from the pure culture must cause the disease when inoculated into healthy laboratory animals

4. The pathogene must be isolated from the inoculated animal and must be shown to be the original organism

1. Some Micro organisms could not be cultured in artificial media - need to use another means such as tissue cells

2.Diseases caused by different species of Microorganisms could elicit similar symptoms

3.Some Pathogenes can cause several disease conditions

Scrapings from cowpox blisters innoculated into healthy volunteer

Volunteer became midly sick and recovered

never contracted either cowpox or small pox again

Vaccine for Small pox was developed!

Theory confirmed by Pasture after 80 years using Bacteria that causes Fowl cholera