While potatoes can be safely canned (if done according to the directions provided by the National Center for Home Food Preservation), it is important to use the right potatoes, the right size, and the use of a pressure canner. While there has been no further information provided at this point related to the canning procedures used or issues seen on other containers processed that may be still in storage, potatoes can become an issue if not done correctly. First, potatoes are low acid, so a pressure canner must be used. Second, it is important the type and the size are correct to allow proper heat movement within the jar (convection heating). If the size is too big or the potatoes break down during processing, the heating parameters within the jar will change, thus affecting the ability of heat to reach the cold spot of the jar.
Another issue is the use of home canned foods for volunteer events. Generally, bringing home canned foods to volunteer events is discouraged. In Penn State's Volunteer Food Safety Curriculum, Cooking for Crowds, it states in Chapter 4:
As a precaution, never accept any home-canned or home-preserved food [for volunteer events]. Life-threatening foodborne illness can occur from food that has been preserved incorrectlyThe same must be said for using canned foods as an ingredient in dishes that will be brought and served at group functions. There are no regulations for these volunteer groups and their functions however and so it comes down to the individual groups to require training and to institute policies.
Getting home preservers to follow scientifically developed recipes is not an easy. Cases like this are reminders that improper canning procedures can lead to deadly consequences.
Source of deadly botulism outbreak in Ohio identified
April 28, 2015, 9:46 AM
LANCASTER, Ohio -- Health officials say the likely source of the botulism outbreak that killed one person and sickened many others at an Ohio church potluck dinner was home-canned potatoes used in a potato salad.
The Ohio Department of Health said Monday that testing has narrowed the source to potato salad served at the April 19 potluck at Cross Pointe Free Will Baptist Church in Lancaster, which is southeast of Columbus.
CBS Columbus affiliate WBNS-TV reports that about 50 to 60 people are believed to have eaten at the potluck dinner, including 10 children.
A 55-year-old woman died, and officials have confirmed 20 other botulism cases, along with 10 suspected cases. A dozen people are still in the hospital. Patients have been treated with a botulism antitoxin provided by the Centers for Disease Control and Prevention.
Botulism is a rare but serious illness caused by a nerve toxin that is produced by certain kinds of bacteria.
The CDC says symptoms of botulism can include blurred or double vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth, and muscle weakness -- a result of muscle paralysis caused by the toxin. Without treatment, the paralysis can progress to affect the respiratory muscles, arms, legs, and torso.