Food Safety and Water Pasteurization

Guest: Dr. Bob Metcalf
Recorded December 1, 2002

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Read the transcript here: English, Spanish

Dr. Bob Metcalf, one of the original founders of Solar Cookers International (SCI), is a professor in microbiology at California State University at Sacramento. Bob has traveled extensively on projects for SCI, working cooperatively with the UNHCR, Plan International, World Vision, and other international organizations. His specialty lately has been solar water pasteurization.

Bob was selected as the 2000-2001 Outstanding Teacher in the College of Natural Sciences and Mathematics at California State University in Sacramento, California. Award criteria include teaching effectiveness and impact on the lives and careers of students. Dr. Metcalf is well known for his work with solar cookers and solar water pasteurization in many countries around the world.

During the broadcast we have Bob explain how he has been able to confirm that contaminated water only has to be heated to 65 C to make it safe to drink, while most of the world still believes that water has to be boiled for 20 minutes. Bob also shares with us experiences and lessons from his recent visits to Africa where he dealt with water quality and solar pasteurization on the ground. Please email any questions of your own to and we'll have Bob answer them.

In preparation for the broadcast, you might want to review some of Bob Metcalf's published papers, audio presentations, and related materials:

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