CDC provided an outbreak report from a June of 2018 incident where three women suffered botulinum poisoning after eating homemade potato salad using improperly processed home-canned peas.
According to the report, the woman's freezer had malfunctioned and so decided to rescue the commercially produced frozen peas by canning them. HOWEVER, Instead of using a pressure canner, she decided to follow a peach recipe that utilizes a water bath canner, and simply substitute the peas for peaches. When a jar lost vacuum, she refrigerated it and used that to make the potato salad.
From the report, "The patient who prepared the home-canned peas was a novice home canner. She used a peach preserves recipe with a boiling water technique, replacing the peaches with frozen vegetables. The patient was unaware that low-acid foods (e.g., vegetables) must be canned in a pressure canner rather than a boiling water canner to eliminate C. botulinum spores (1). After the jars cooled, the patient correctly checked for jar seal. One of the jars of peas was not sealed, so the patient covered and refrigerated it, and the family consumed the peas in the potato salad."
The women who had arrived at a hospital 4 hours earlier for evaluation for acute nausea, dizziness, blurred vision, slurred speech, ptosis, thick-feeling tongue, and shortness of breath. Two patients developed respiratory failure, requiring intubation and mechanical ventilation in the emergency department, and the third patient was intubated at 7 p.m. that evening. The combination of cranial nerve palsies and respiratory failure in multiple patients suggested botulism, a paralytic illness caused by botulinum neurotoxin (BoNT), most commonly produced by Clostridium botulinum.
As we know, when you have low acid foods, they must be pressure canned in order to destroy any Clostridium botulinum spores. In peaches, the acidity is high / ph is low (<4.6) and that prevents the spores from growing, so a high heat treatment is needed. In peas, a low acid food, the acidity is low and the pH is high (>4.6). In this product, the spores survived the milder heat treatment used in the water bath canning, and when the product cooled down, the spores germinated and grew in the peas, producing the deadly neurotoxin.
https://www.cdc.gov/mmwr/volumes/68/wr/mm6810a5.htm?s_cid=mm6810a5_e
Notes from the Field: Botulism Outbreak Associated with Home-Canned Peas — New York City, 2018
Weekly / March 15, 2019 / 68(10);251–252
