While preservatives may have a bad nutritional rap, the truth is that these substances allow seasonal food to be consumed throughout the year, and in areas where it would otherwise be unavailable. Methods of food preservation such as salting, drying, and smoking have been practiced for millennia, while others have been made possible on a commercial scale by technological advances such as freezing and pasteurizing. This program takes a look at the how and why of food preservation, covering a variety of techniques and explaining the differences between natural and artificial preservatives.

Encoded with permission for digital streaming by Infobase on January 12, 2013. Learn360 is distributed by Infobase for Films for the Humanities & Sciences, Cambridge Educational, Meridian Education, and Shopware.

Reasons for Preserving Food (1:23) -- Processes and Benefits of Preservation (1:17) -- Causes of Food Spoilage (1:34) -- Environmental Causes of Spoilage (2:10) -- Preservatives: Natural and Chemical (3:00) -- Pickling and Fermentation (1:26) -- Chemical Preservatives and Irradiation (1:03) -- Preservation Techniques Using Temperature (1:32) -- Preserving by Raising Temperature (2:43) -- Preservation Techniques: Water and Oxygen Removal (2:09) -- Vacuum Packing (0:58) -- Credits: Food Preservation Techniques (0:42).