How to Think Like a Bug in Food
As they say on one of my favorite shows, Criminal Minds, "To catch a criminal, you have to think like one." The same applies to bacteria. In our earlier blog post, 'How to think like a bug', we shared some insight to help design your environmental sampling practices. With our focus on finished product, we will explore how bacteria interact with food matrices.
The bacteria that cause food-borne illnesses are microscopic, invisible to the naked eye. Often, there are no visual changes or odors to indicate contamination. Also many pathogens have a lengthly incubation period so, people may not get sick immediately after eating the contaminated food. This is because initially the ‘bugs’ found in food are damaged and starved for nutrients, slowing down their metabolism. However, once ingested, they find more favorable conditions for growth, their metabolic machinery starts working aggressively and they start multiplying exponentially.
But each bacteria is a little different. The generation lengths (the time that it takes one bacterium to accumulate enough material to split) vary greatly between different genus and species of bacteria but regardless, the population growth curve is exponential. The bacteria rob the body of nutrients and produce poison-like toxins. These toxins are responsible for the primary symptoms associated with food-borne illnesses.
Most organisms that cause food-borne illnesses need the right conditions to grow and spread. The acronym FATTOM presents a simple yet easy way to remember the kinds of environments that bacteria like.
Food: Just like humans, bacteria need food to grow. They especially thrive on foods with a lot of protein (meat, milk, eggs, fish). That’s why these kinds of foods are more likely than some others to carry food-borne illnesses.
Acidity: Bacteria don’t like acidity. Most don’t do well in strongly acidic environments. So, the level of acid content in food or environment can create favorable or unfavorable condition for bacteria to grow and survive.
Time: Bacteria like to settle in, make themselves at home. The more time they spend the more comfortable they become. Under favorable conditions, bacteria grow and multiply extremely quickly.
Temperature: Bacteria like warm environments, around room temperature. They don’t like extreme cold or extreme heat. However, Listeria is an exception. It can survive cold or even freezing temperatures.
Oxygen: Most bacteria need oxygen to grow.
Moisture: Bacteria love moist environments. Soft cheeses and meat are very moist and provide hospitable environments for bacteria.
Environmental testing is a critical component in ensuring that bacteria does not find its way into finished product. Finished product testing is an important confirmation step. Generating results quickly enable reaction time for your environmental program and reduce the logistics burden in your finished product testing. Our pilot program was critical to the development of DETECT/L.
Over the next year, we will be adding more matrices and more pathogens in our quest to make food safer.