Dear Mr. Rawles,
I thought that the free food preservation course from the National Center for Home Food Preservation would be useful to your readers. Here are some details, from their web site:
Preserving food at home, a self-study course.
Announcing a free, self-paced, online course for those wanting to learn more about home canning and preservation.
* Introduction to Food Preservation
* General Canning
* Canning Acid Foods
* Canning Low-Acid FoodsThis course is offered in the University of Georgia eLC system. The univefrsity requires registration for you to receive a login.
– David L.