Food contamination essentially refers to a foreign thing getting into the food that should not be there, making the food unsafe to consume. Even the most minor form of food contamination can sometimes cause serious food safety concerns as it may cause the consumer to fall sick or, even worse, a foodborne illness outbreak. Food safety is paramount for food businesses and restaurants, as a single case of food poisoning can tarnish their image and invite legal trouble.
What are the Types of Food Contamination?
Even while adhering to the best food safety standards, sometimes something unwanted gets added to the food resulting in physical contamination. This could be something in the form of a physical substance like plastic or nail pin or something chemical, like washing powder. The chances of food contamination depend on the food preparation process and the number of handlers the food passes through. There are four main types of food contamination:
1. Physical Contamination:
Physical contamination happens when a physical object like plastic, nail, screws or even hair falls into the food when being prepared or served. Ideally, they are easy to separate and cause less impact on the food. Still, they are the most common form of food contamination.
2. Biological Contamination:
Biological Contamination happens when the food gets infected by certain living organisms like Norovirus, Salmonella, E.coli, and more. Such viruses are transferred from rodents, animals and even humans. As a result, they pose a severe threat to food safety as they can lead to a foodborne illness outbreak.
3. Chemical Contamination:
Various chemicals are used in the kitchen for cleaning, disinfection and other purposes. However, when such chemicals get mixed with the food, they cause chemical contamination. Therefore, they can result in dire consequences if such food is consumed.
4. Allergic Contamination:
People have different allergies, such as peanuts, gluten, mustard, eggs, etc. Allergic contamination happens when one of such components gets mixed with the food unknowingly and is served. Its consumption can trigger an allergic reaction.
Apart from the above four forms of food contamination, there is also cross-food contamination which can be a mix of any of the above four types. Whatever the kind of food contamination, it poses severe threats to food safety. Therefore, it needs to be avoided at all costs. Let us now look at each type in greater detail to understand their causes and impact.
What is Physical Contamination?
Food preparation is a multidimensional process and involves many raw materials. Many people are involved in the process in hotels and restaurants with bigger kitchens. At any step, there are chances that an unwanted object gets added to the food. Such an object could become a choking hazard and add biological contaminants to the food, making the risk more severe. Even if the physical contaminant is discovered before consumption, finding physical contaminants in their food will distress the customer and result in a bad reputation.
Physical contamination continues to remain the most prominent form of food contamination across the globe. According to FDA, in 2018, physical food contamination resulted in 53% of food recalls in the USA. Such a high number is also because it is easy to detect physical contamination as physical contaminants are generally visible. While for other forms of food contamination, it may be challenging to identify contamination. Establishing robust food safety processes and ensuring a safe and healthy food premise are foundational elements to prevent physical contamination.
What are the Most Common Physical contaminants?
Any foreign object which is not supposed to be the food ingredient can be considered a physical contaminant. Given the preparation and handling process, the following are the items that make up the most common physical contaminants:
- Broken glass
- Screws or pins
- Bones or shells
- Tin foil
Physical Contamination Examples
The chef has prepared a delicious hot plate of pasta to be delivered to customers at Table 6 in an Italian restaurant. While serving the steaming hot food, the fake nails of the waitress get dislodged due to the heat and mixed with the pasta. The customer discovers the nail while taking his first bite and is obviously unhappy. This food physical contamination incident could have been avoided with a “no fake nails or eyelashes” food safety policy.
While having breakfast at a buffet in a 4-star hotel, Brendon discovers a small metallic object in his porridge. Upon closer inspection, he found that it was a screw that had fallen off the lid used on the porridge vessel. In the morning hustle, the servers would not have noticed the loose screw, which resulted in a serious food safety breach. Hence food preparation and serving premises must be kept clean and safe from physical contaminants.
Post her office, when Sarah was having a cup of coffee at her usual diner, she experienced a prick in her mouth. She quickly examined it to find a small staple pin stuck in her gum. She removed it with caution. The pin had entered the mouth along with the coffee and caused this physical contamination. It is likely that while opening food materials, one of the staple pins would have found its way to the cup or the raw material and thereby caused this physical food contamination.
What is Biological Contamination?
Biological contamination occurs when the food is infested with certain harmful microorganisms like bacteria, viruses, fungi and other microbial toxins. This is why such type of contamination is also known as microbial contamination of food. Such contamination is hard to detect through the naked eye. It can only be known once the contaminated food is consumed and the consumer starts to show the ill effects.
Biological contamination of food continues to be the biggest cause of foodborne illnesses. According to the CDC, such type of foodborne illness impacts about one in every sixth person in the USA. Unlike physical contamination, biological contamination has very dire effects on consumers. Within hours or days, they start to show symptoms like stomach ache, dizziness, diarrhoea, vomiting, dehydration and many more. Severe effects can cause hospitalization or even death.
What are the Most Common Biological contaminants?
There is a wide range of fungi, bacteria and viruses that may enter the food in the course of its preparation, cooking or even serving. Such viruses vary from food types and geographical conditions, but the most common ones are:
- E. coli
- Hepatitis A
Each of these viruses showcases different symptoms in the consumer and poses various levels of threats to them. Some contaminate the food from its production stage by ingesting the raw materials. Other viruses or bacteria are produced during the food preparation process. Not storing food at the correct temperatures or undercooking meat are some of the common causes of food microbial contamination. However, the most common source is the food handler. If they are hosts to any of these viruses, they will pass it on to all the food they come in contact with.
While the sources may differ, the end result is always worrying. The USA has already witnessed more than 20 such outbreaks in 2022 so far. Such outbreaks not only endanger people’s lives but cause a bad reputation for the origin restaurants. Some notable cases have been the Chipotle Mexican Grill E.coli outbreak which affected over 55 people in 11 states. In 2002, Pilgrim’s Pride sliced turkey deli meat caused a Listeria outbreak of Listeria in 8 states, causing ten deaths. As a result, the company had to recall 27.4 million pounds of its poultry products. In 2006, Dole baby spinach caused E.coli infection affecting over 300 people in 26 states.
Robust food safety processes and strict compliance are needed to avoid food microbial contamination. The chances of biological food contamination are very high in uncooked food. Hence, they must be dealt with with caution. Also, the food sources, be they farms or dairies, need to be bound by food safety guidelines. Meat and other food materials must be stored and cooked at specific temperatures. At the same time, cooks and food handlers should be educated about such biological food contamination. These steps can go a long way in keeping food safe from microbial contamination.
What is Chemical Contamination?
Various chemicals are used in the kitchen for cleaning, food treatment, disinfection, pest control system and other purposes. Some such chemicals may get mixed with the food, resulting in food chemical contamination. The food preparation area is not thoroughly cleaned of the washing powder or liquid, or sometimes the raw materials are not entirely cleansed of the cleaning fluid. There are chances of chemical contamination even at the raw materials stage, as they might be infected with fertilizers, pesticides or insecticides.
The sources can be multiple, but the outcome of such contamination can lead to severe food safety risks. Unlike physical food contamination, it is hard to detect chemical contamination of food. This is all the more challenging in cases of liquids where the chances of contamination are higher. The ill effects of chemical contamination range from mild headaches to vomiting, diarrhoea to even fatalities. Particular chemical contaminations also have long terms effects.
What are the Most Common Chemical Contaminants?
As only certain types of chemicals are used in food preparation and other auxiliary tasks, they are the most common chemical contaminants. At the same time, there are chances of any types of chemicals being mixed with food if proper care is not taken. The following are the most common chemical contaminants which can be categorized as natural and artificial:
- Pesticides / Insecticides
- Cleaning products (e.g. detergents, sanitizers)
- Heavy metals like lead, mercury, cadmium
- Naturally occurring toxins like mycotoxins, marine biotoxins, cyanogenic glycosides
- Persistent organic pollutants like dioxins and polychlorinated biphenyls
Given the high-risk chemical food contamination pose, food businesses must deploy strong food safety practices to mitigate the contamination risk. It is advisable to have separate storage areas for chemicals far from food or raw materials. While cleaning the kitchen, food should be covered. The cleaners should ensure that the cleaning solution is wiped from all food preparation surfaces.
Manufacturers’ instructions regarding the use of chemicals should always be followed. Care needs to be taken so that there is no contamination from the food source as well. These precautions will help ensure the food served is free from toxic contaminants.
What is Allergenic Food Contamination?
Usually, food contamination is classified into three broad categories. But there is one more category that deals with specific food allergies that people have. People allergic to certain food items always mention the same in their order, and the cook ensures that these items are not added to the food served. But there are times when inadvertently one or some such items get mixed with the food, resulting in allergenic food contamination. When such food allergenic contamination occurs, it will trigger an allergic reaction in the consumer leading to health issues.
The major sources of this contamination are the food handlers or the cooks. Some examples of allergenic food contamination include using the same knife used to cut common bread for gluten-free bread, storing Pasta in a tub used to store peanuts, or unknowingly adding a mustard-based sauce. The ill effects of such contamination vary on the type of allergens and the consumers. They can range from vomiting and nausea to even critical hospitalization. There have been cases where the consumption of even a small amount of allergenic contamination has resulted in fatalities.
What are the Most Common Allergenic Contaminants?
According to FDA, there are eight major allergens. Following is the list of the major allergens:
- Fish (e.g., bass, flounder, cod)
- Crustacean shellfish (e.g., crab, lobster, shrimp)
- Tree nuts (e.g., almonds, walnuts, pecans)
Apart from the above, there are other forms of allergies like Lupin, mollusc, mustard, sesame seed and others. One person can be allergic to more than one type of food item. Big kitchens must take great care to prevent physical contamination or cross-contamination. Proper infrastructure and operational practices must be strictly implemented to prevent allergenic contamination. Food utensils, clothes, and storage should be separated for particular allergens. Kitchens and food storage areas should be thoroughly cleaned to avoid cross-contamination of allergens.
10 Tips to Avoid Food Contamination:
Food contamination can have dire consequences for the person consuming contaminated food and also for the restaurant serving it. While the latest stringent food regulation norms ensure that restaurants take utmost care while preparing and serving food, there are still chances of physical contamination. Following are some essential tips that can help in minimizing food safety risks:
1. Wash hands regularly:
Primary food hygiene starts with washing your hands regularly. This habit becomes more critical in bigger kitchens when cooks or even food handlers are working on multiple types of foods. Washing hands will ensure that your hands remain clean and eliminate the risk of cross-contamination.
2. Keep kitchen area clean:
Along with hands, the kitchen area must be kept clean. Cooks should make a practice of cleaning the workstation every time they start working on something new. In addition, unwanted food material should be stowed away, so there are no chances of any physical contaminants mixing with food.
3. Earmark separate utensils:
In multi-cuisine restaurants, it is essential to have separate utensils and tools earmarked for particular purposes. One good practice is to have a different infrastructure setup dealing with allergen food preparations. Apart from that, it is essential to have dedicated tools for vegetarian and vegan food preparations and food serving.
4. Store raw meat separately:
Raw meat is one of the biggest culprits concerning food microbial contamination. Make sure the meat is stored separately as there are chances that the bacteria formed on meat can pass on to salads or other raw materials resulting in foodborne illness. Establishing a meat storage and usage policy is vital for big restaurants.
5. Keep track of expiry dates:
There is a reason why expiry dates or best-before dates are provided for all food products. Strictly adhere to these dates, as any lapses can result in adverse consequences. Another critical factor is disposing of stale or expired food products. Have a set process for storing them separately and disposing of them.
6. Ensure the proper temperatures:
Correct temperatures play an important role in storage and cooking. Keeping your refrigerator below 5 degrees celsius is good practice as it ensures that no food poisoning bugs are growing in your food. Regarding cooking, meat and other such components must be cooked at the proper high temperatures to ensure they are safe to consume.
7. Store non-food material separately:
Many chemical food contamination cases happen because cleaning products are stored along with food. If there are spillovers or leakages of such materials, they can be mixed with raw food materials. Hence, it is better to have a dedicated storage area marked for non-food material at a distance from edible items.
8. Keep food covered:
An elementary practice of keeping the food covered can help avoid physical contamination of food. If the food is ready and kept in the open, there are chances of insects, flies, hair or other particles flying in from the air to drop into the food. Therefore, keeping the food covered as much as possible is good practice, especially once it is ready to be served.
9. Deep clean the kitchen regularly:
While it is a good practice to clean the kitchen daily, having it thoroughly cleaned daily is not practical. Hence, establish the good practice of having deep cleaning sessions weekly or fortnightly. Remove unwanted items from near the worktops, inspect the fittings and run other checks in the food premises to reduce contamination risks when working.
10. Keep sick workers away from food:
One of the most common sources of contamination is the food handlers themselves. If the cook or other people working in the kitchen are sick, they are also bound to infect the food. The risks become all the more severe when they have contracted any foodborne illness. Many outbreaks in the past have been linked to sick workers making or serving food. Hence it is a good practice to keep sick workers away from food.
Food contamination is one of the most significant food safety risks and should not be taken lightly by any food-related businesses. Every year, millions of people worldwide get sick because of some or other type of food poisoning or food allergies. While the majority experience only light symptoms, for some, such contamination-induced illnesses can also prove fatal.
Understanding the kind of contamination and its sources is crucial. And it is also essential that all the people related to the entire food processing chain, the food producers, food handlers, cooks or servers, be aware of the risks and should be trained to mitigate them. Reducing the risks of food contamination will result in safe and healthy food for all.