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1102 Types of Food Contaminants

Written by CAIBOK on . Posted in 1100 Safety White Belt.

Preventing food contamination is a critical responsibility for foodservice workers. Understanding how biological, chemical, and physical contaminants affect food safety is essential in reducing the risk of foodborne illnesses. This section covers the different types of contaminants, how they spread, and the practical steps food handlers can take to prevent them. Additionally, it explains how to manage common food allergens and outlines the proper response to a foodborne illness outbreak, ensuring food safety is maintained at every level of operation.

Avoiding Food Contamination

Sickness from bad food can be prevented if everyone understands how food can become contaminated, and is careful to prevent it. In this section, you will learn about:

  • Biological, chemical, and physical contaminants, and how to prevent them
  • Protecting food from intentional contamination
  • How to respond if a foodborne illness occurs
  • Common food allergens and how to prevent allergic reactions

Understanding Contaminants

One of the main responsibilities of a food service manager is making sure food doesn’t get contaminated. Contaminants are substances that can harm food, leading to illness or injury. These harmful substances are typically categorized as biological, chemical, or physical.

How Contamination Occurs

Contaminants come from many different places. Some can naturally be found in animals used for food, while others come from the environment, like water, air, or dirt. In many cases, contamination happens because of the way food is handled. For example, if food workers don’t wash their hands after using the bathroom, they can spread harmful bacteria from their hands to the food they touch. This is often called the “fecal-oral route” of contamination.

Food can also become contaminated by sneezing or vomiting near food or food-contact surfaces, touching dirty surfaces and then handling food, or through improper storage and handling, such as letting raw meat touch ready-to-eat foods. In addition, pests in foodservice areas can easily spread contaminants.

Biological Contamination

Biological contaminants include microorganisms such as bacteria, viruses, parasites, and fungi. While many microorganisms are harmless, others can make you very sick. Some produce toxins (poisons) that cause illness. Understanding these biological hazards is important to stop foodborne illnesses before they start.

Common Symptoms of Foodborne Illness

The symptoms caused by foodborne illnesses can vary, but the most common ones are diarrhea, vomiting, fever, nausea, stomach cramps, and jaundice (yellowing of the skin or eyes). The time it takes for symptoms to show up after eating contaminated food, known as the onset time, can range from 30 minutes to as long as six weeks.

Bacteria

Bacteria that cause foodborne illnesses have some common traits:

  • Where They Are Found: Bacteria exist nearly everywhere, including on and inside our bodies. While some bacteria are helpful, others are harmful.
  • How They’re Detected: You can’t see, smell, or taste bacteria.
  • Growth: Bacteria grow quickly when conditions are right.
  • Prevention: The best way to stop bacteria from causing illness is to control time and temperature.

How Bacteria Grow: FAT TOM

Six conditions are needed for bacteria to thrive, remembered using the acronym FAT TOM:

  1. Food: Bacteria grow best in certain foods, especially those that need time and temperature control.
  2. Acidity: Bacteria prefer foods that are neutral or slightly acidic.
  3. Temperature: Bacteria grow fastest between 4°C which is 40°F and 60°C which is 140°F. This is known as the “temperature danger zone.”
  4. Time: The more time food spends in the danger zone, the more bacteria can grow.
  5. Oxygen: Some bacteria need oxygen to grow, while others can grow without it.
  6. Moisture: Bacteria multiply rapidly in foods with high moisture content.

Foodservice workers can help stop bacteria by controlling time and temperature—two key factors within their control.

Key Bacteria That Cause Foodborne Illness

Several bacteria are highly contagious and can cause serious illness. These include:

  • Salmonella Typhi: Found in humans and spread through contaminated food and beverages.
  • Shigella spp.: Spread through contaminated food, water, or by flies.
  • E. coli (Shiga toxin-producing): Found in the intestines of cattle and spread through undercooked meat and contaminated produce.

Food handlers diagnosed with illnesses caused by these bacteria must not work while sick.

Viruses

Viruses are passed from humans and animals and need a living host to grow. While viruses can’t grow in food, they can be transferred to it and remain infectious.

  • Sources: Viruses can come from contaminated food, water, or surfaces. Norovirus, a leading cause of foodborne illness, is often spread through airborne vomit particles.
  • Prevention: Since viruses aren’t killed by normal cooking temperatures, good hygiene is the best defense. Quickly cleaning up vomit and practicing proper handwashing are also essential.

The two most common viruses that can cause serious illness are Hepatitis A and Norovirus. If food handlers are diagnosed with these illnesses, they must stay away from the workplace.

Parasites

Parasites need a host, such as an animal or person, to live and reproduce. They are often found in seafood, wild game, and foods processed with contaminated water. To prevent parasitic contamination, food must be sourced from reliable suppliers and cooked to the correct internal temperatures.

Fungi

Fungi, including molds and yeasts, can also lead to foodborne illness. Some molds and mushrooms produce toxins, making it critical to only buy from reputable suppliers. Moldy foods should be discarded unless mold is a natural part of the product.

Biological Toxins

Certain toxins, like those found in plants, mushrooms, and seafood, can make people sick. Some toxins are naturally produced, while others, like histamine, form in fish when they are stored improperly. Cooking or freezing food doesn’t remove toxins, so it’s important to source seafood, mushrooms, and plants from reputable suppliers.

Chemical Contaminants

Chemicals such as cleaners, sanitizers, and even certain types of kitchenware can contaminate food if they aren’t handled properly. To avoid this:

  • Only use approved chemicals for foodservice and follow all instructions.
  • Store chemicals away from food and prep areas.
  • Always use kitchenware that is safe for food.

Physical Contaminants

Food can be contaminated when physical objects like metal shavings, glass, or bones accidentally get into it. This can lead to injuries such as choking or cuts. Food should be inspected closely, and proper hygiene practices must be followed to avoid physical contamination.

Deliberate Contamination of Food

Sometimes, food can be intentionally tampered with. This may be done by disgruntled employees, competitors, or activists. To protect food, it’s important to implement a food defense program. The FDA suggests using the A.L.E.R.T. tool to secure food at every stage of preparation and delivery:

  • Assure: Make sure products come from safe sources.
  • Look: Keep an eye on food security throughout your facility.
  • Employees: Know who is in your establishment and limit access to food storage and prep areas.
  • Reports: Maintain records on food defense measures.
  • Threat: Have a plan in place in case of suspicious activity or contamination.

Responding to a Foodborne Illness Outbreak

If a foodborne illness occurs, follow these steps:

  • Collect Information: Get details from the person reporting the illness, including what they ate and when symptoms began.
  • Contact Authorities: Notify the local health department if necessary.
  • Isolate Suspected Food: Label any suspected food as “Do Not Use” and set it aside.
  • Document: Record details about the suspected product, such as lot numbers and production dates.
  • Identify Staff: Make a list of food handlers working during the time of the incident.
  • Cooperate: Work with the health department and provide necessary records.
  • Review Procedures: Evaluate your food handling processes to see what may have gone wrong.

Food Allergens

Food allergens are naturally occurring proteins in food that cause allergic reactions in some people. The most common allergens are:

  • Milk
  • Eggs
  • Fish
  • Shellfish (e.g., shrimp, lobster)
  • Wheat
  • Soy
  • Peanut
  • Tree nuts (e.g., almonds, walnuts)

Preventing Allergic Reactions

Both kitchen and service staff must play a role in preventing allergic reactions:

  • Service Staff: Must be able to inform customers about menu items that contain allergens.
  • Kitchen Staff: Must prevent cross-contact by ensuring allergens don’t accidentally get into other foods, such as by using separate utensils and cooking surfaces.

By following these guidelines, foodservice workers can significantly reduce the risk of foodborne illnesses and allergic reactions, ensuring the safety of their customers.