Science and Our Food Supply: Investigating Food Safety from Farm to Table

Did you know that there are many ways to control bacteria 

during processing and transportation? This module focuses 

on several methods scientists use to keep our food safe. 

MODULE

3

PROCESSING AND 

TRANSPORTATION 

SCIENCE CONTENT

This section explains the specific science concepts 

presented in Module 3 of the video, including 

fascinating facts relative to the module. Read this 

section before watching the video module or  

conducting the activities and labs. 

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MIDDLE LEVEL

PROCESSING

Food safety plays a major role throughout food processing. 

Pasteurization 

Pasteurization is the process of using heat or irradiation to destroy microorganisms 

that could cause disease. Today’s modern dairy farms may house up to 5,000 cows 

each. All the farm’s milk is pooled, so if one cow is sick, there is a possibility to  

contaminate all the milk. That’s why milk is pasteurized. 

Milk was one of the first products to be pasteurized on a broad scale. In addition to 

dairy products, other pasteurized foods include fruit juices, chicken, beef, and spices. 

One challenge scientists faced was trying to figure out how to pasteurize an egg  

without cooking it. The solution was to heat the eggs up slowly to 135° F (57° C)  

and maintain that temperature for 1 hour and 15 minutes. This time/temperature 

relationship inactivates the bacteria while keeping the eggs fluid. 

Louis Pasteur (1822–1895), a chemist, was actually trying to prevent spoilage in wine 

and beer when he discovered pasteurization. Pasteurization was applied first in wine 

preservation. When milk producers adopted the process, it reduced foodborne illness 

substantially. You never know where science will lead you!