Botulism is one of the deadliest forms of food poisoning that every charcutier must be acutely aware. The chances of contracting botulism are rare, but the effects can be fatal. Botulism spores can produce a deadly toxin that is not detectable by color or smell, but can be easily prevented by using proper technique and curing agents.
There is more than one way to contract botulism, but the form of botulism poisoning that applies to the charcutier is food borne botulism. This form of food poisoning has existed since the dawn of man, but up until the 18th century, these deaths fell under the category of ‘natural causes.’ The earliest documentation of this illness was in the 10th century when Emperor Leo VI of Byzantium prohibited the manufacturing of blood sausage after an outbreak of food poisoning. Another outbreak of ‘sausage poisoning’ in southern Germany at the end of the 18th century motivated Justinus Kerner, a German poet and medical officer, to investigate the causes. Although he is not responsible for discovering the bacteria that is responsible for botulism poisoning, he was the first to document the descriptions of this ‘sausage poison’, noting that it is commonly found in improperly handled meats. He also coined the name botulism, which is derived from the Latin word for sausage, botulus. Kerner’s work was published between 1817-1822. In 1897, a man named Emile Van Ermengem discovered that the producer of the botulin toxin was a bacterium, which he named Clostridium botulinum. More research followed over the years and in 1949, after managing to purify the toxin, the complete effects of the botulinum toxin on the human body had been identified. A treatment was discovered in the early 1970’s.
Clostridium Botulinum is a bacteria found in soil all over the world and botulism spores are found in every type of meat or vegetable. These spores and bacteria aren’t harmful on their own, but when left in an environment between 40°F and 140°F (known in food safety terms as the ‘temperature danger zone’) with little oxygen and slight acidity (like the inside of a sausage), the bacteria will produce the deadly botulinum toxin. As mentioned earlier, the botulinum toxin is not detectable by sight or smell. Symptoms will usually appear within 2-72 hours, but, in rare instances, can present themselves up to 10 days after consumption of the toxin. The first symptoms will be blurred and/or double vision, dry mouth, vomiting, drooping eyelids, and difficulty swallowing. Slurred speech will follow with difficulty holding up the head, as the neck and throat muscles become severely weakened. If left untreated, symptoms will progress until the body is in full paralysis and can lead to eventual death by respiratory failure. Without treatment, it’s all over in about three days.
Smoking and dry-curing meat creates the ideal environment for the botulin toxin to thrive. Cold smoking is done in a low oxygen chamber with temperatures between 70°F-100°F for several hours and sometimes up to several days; dry-curing meats (such as salami) requires fermenting the meat at room temperature with 60%-70% humidity. Anytime meat is cured or prepared in a way that will leave it in the temperature danger zone (40°F-140°F) for longer than several hours, a cure containing sodium nitrates or sodium nitrites is required to prevent the botulin toxin from developing. Nitrates or Nitrites are only needed when smoking or dry-curing meats; if you make a fresh sausage and plan to either immediately refrigerate it (keeping it below 40°F) or cook it quickly at a temperature above 140°F, no curing is needed. When dry-curing meat the use of sodium nitrates/nitrites is imperative and in regards to smoking meat the bottom line is this: If it can’t be cured, don’t smoke it!