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Module 1 - Food Safety Questions With Complete Solutions food industry anything from food production, manufacturing, transportation, distribution, preparation and there are other factors about 1/4th of all employees work in food food industry produces about 20% of America's gross domestic product average grocery store stocks nearly 55,000 items Contamination refers to the presence of substances or conditions in the food that can be harmful to humans There were two reports that came out from the CDC in 2011 that estimate the foodborne disease burden in the United States. In the US, we would have about 50 million illnesses every single year. We also have about 127,000 hospitalizations and about 3,000 deaths. There are a lot of studies that suggest that we could be doing a lot to prevent many of these illnesses and of course many of the deaths
foodborne diseases occur in three different types and these depend on what sort of pathogen is involved Infection Intoxication toxin-mediated Infection caused by eating food that contains living disease-causing microorganisms intoxication These are caused by eating food that contains a harmful chemical or toxin produced by bacteria. When you have an intoxication, the symptoms can occur very rapidly. toxin-mediated middle ground between these two You have to imagine that once that microorganism is swallowed, it can become established in your gut. Once it becomes established in your gut, then it begins to produce a toxin in your body. And again this is known as toxin-mediated. Sometimes toxin-mediated diseases can take 48-72 hours to create symptoms.
foods prepared outside of the home. And those also have unique challenges. A globalized food trade exists currently and this can create some issues in terms of pathogens We also have improved transportation. So for example, if you think about it, how quickly can you leave Florida and be in another country? There are growing populations that require greater quantities of nutritious and safe food. Unfortunately, many of these people live in places where you cannot produce food so that food has to be imported from another place. And as I mentioned before, there is a growing demand for ethnic foods and that is increasing the number of imports obal food trade can be problematic because it leads to the following food safety risks. There is the possibility that you could introduce a new pathogen. There is also the possibility of re-emergence of an old pathogen Ex: Trichinella really doesn't exist in the United States anymore but there is also a possibility of it becoming imported once again. And then there is the spread of contaminated foods across greater geographic areas leading to worldwide illnesses.
Ready-to-eat foods are those foods that do not require washing, cooking, or additional preparation by the consumer. Careful handling however is required to ensure that these products do not contain contaminants. Why this is important is that we have seen a number of outbreaks recently that are linked to these foods. So for example, bagged salad mixes have been one of the leading foods recalled in recent years due to microbial contamination There are some food products that are considered potentially hazardous. They possess characteristics that make them suitable for microbial growth And those are the following; foods that have high protein and high carbohydrate are excellent for microbial growth. Those proteins and carbohydrates provide food sources for the microbes. Also, a pH above 4.6 is important. Some microorganisms are sensitive to acidic conditions and they do not like low pHs. They also like water. With some exceptions, the fungi in general are not all that thrilled with water and we will talk about how those are unique later on [Note added: they can tolerate water, and some thrive, but many enjoy drier conditions]. So water activity above 0.85 leads to greater microbial growth.
poor hygiene practices cross contamination occurs when contaminants such as bacteria are spread from one type of food to another. Often what happens here is that you have a food preparing that is doing something like making raw meat and they are also making a salad. However, they are using the same utensils or the same cutting board or the same countertop and some of the raw meat or the juices from that raw meat ends up in the salad. So the results are that an organisms that would normally be destroyed by cooking is spread to a food group that is not cooked. For example, one of the big problem foods for cross contamination is chicken. So I included this picture here to let you know that about 90% of grocery-brought chicken contains Campylobacter. That is a human pathogen and it is often spread by cross-contamination. agroterrorism So it is very possible that some of those persons may try to deliberately contaminate foods. There are a large number of food products and safety regulations for all of those products are very challenging. Keep in mind that
we can order food from the internet now [note: think about long distance orders such as Amazon]. You can have things coming through the mail that may not have gone through the safety checks that you would have liked. There are a large number of imported foods. There are millions of people involved in food production. You can have anything occur from a person who is simply angry at a company and therefore contaminates their food to the end-line user who does not like you and spits in your Coca-cola before filling your cup at the drive-thru. There are also a large number of food establishments and policing all of these really is impossible. So we do know that the food supply is vulnerable. Usually the goal of agroterrorism is economic harm rather than killing individuals bioterrorism intentional food poisoning Salmonella, Shigella, and Staphylococcus aureus are most common HACCP
factors but the biological agents (bacteria, viruses, etc) are responsibly for greater than 95% of foodborne illnesses and nearly all of the deaths. Understanding the factors behind the spread of foodborne diseases is key to their prevention. I also want to note here that students often skip over the objectives and summaries while they are studying for the exams. raw produce as it related to food safety issues The FDA fully supports an increase in consumption of fruits and vegetables but does not endorse raw diets. The reason the FDA does not endorse raw diets is because many of the pathogens found in raw produce are destroyed by cooking. So you may have noticed that there have been recent recalls due to contaminated bagged lettuce, and spinach. In the case of the spinach, if it had been cooked you would have seen destruction of the pathogens. risks associated with raw milk Recently there has been increased interest in consumption of raw milk due to claims of everything from loss of calcium to the dangerous side effects of pasteurization. I want you to note that the things you read about health and foods, and especially if you are using social media as your source of information, are very very frequently not true. As is the case here. Pasteurization does not change the calcium
content of milk and it does not produce dangerous side effects. The FDA has launched a campaign to warn consumers of the risks of raw milk following several outbreaks of dangerous microorganisms including Listeria and E. coli. If you were to search for interest groups that sell raw milk, one of the things they will tell you is that raw milk contains natural microorganisms that will kill pathogens This simple is not true. There are several families that have recorded videos of illnesses that have occurred due to consumption of raw milk. I would encourage you if you are interested at all in raw milk, or in prevention of diseases linked to raw milk, to go ahead and check out the website that is shown here. You can see some of the problems that have occurred with raw milk. Food safety experts do not support the consumption of raw milk and legislation banning the sale of raw milk for human consumption is in place in many states including Florida. In Florida, we do allow the sale of raw milk for animal consumption. However, we don't allow the consumption by humans, creating
The take home message on this is that the science is not clear whether the pesticide use effects the quantity and quality of microorganisms found in the foods. Many products are on the market that are labeled "organic" but do not meet the USDA/FDA organic guidelines. The price of organic foods is significantly higher. Animal manure significant problem related to organic farming commonly in both home and large-scale organic farming. Chicken manure can potentially include dangerous pathogens such as Salmonella, E. coli, and Listeria. In fact, it has been highly recommended that if you do use manure in home farming, do not use chicken manure. However, as you can see in the picture on the right, if you do a simple Google search for chicken manure, you can find it for sale from a number of different places. Many have suggested that the use of animal manure in organic farming poses a risk to the consumer The FDA has proposed new guidelines concerning the use of animal manure
So data supports long term survival of dangerous microorganisms in soil containing manure and therefore the FDA is proposing restrictions on use of manure in farming. So this is not a law, this proposal has been met with strong opposition from the organic food industry. As of today it is still not law. Why the FDA is concerned is because if you introduce a pathogen like Salmonella to the soil, it is able to enter the roots and climb into the fruit. So various plants like tomatoes for example can become contaminated with Salmonella on the inside of the tomato organic foods are neither healthier nor safer than conventional foods So now we turn our discussion to imported foods and why they are concerns for food safety. One major concern with imported foods is the unintentional importation of a food pathogen not present in the United States. So you probably know that we are physically unable to screen every single thing that comes into the United States. Some foods will come in without the benefit of inspection by Border Control [Note added: FDA can do inspections at border]. Food Safety Modernization Act (FSMA) will ostensibly make imported foods much safer So it may surprise you to know that the United States is considered to have the safest food supply in the world.
So you take this tool here and punch out a piece of the tissue. You can then do histology and look to see if Trichinella is present in the tissue. So it is definitely not easy to do. Taenia solium pork tapeworm. When the larvae are consumed, they are relatively harmless However, when the eggs are consumed they migrate to the brain causing a disease known as neurocysticercosis. If you look at the image of the brain you can see holes where the pathogen has done damage. Often this is diagnosed as brain tumors and surgery is undertaken. When they open up the skull for surgery they find live Taenia present prions mad cow disease is caused by and to put that into perspective if you are wondering how serious are the new pathogens, so far 226 (as of 2012) people linked to the mad cow disease outbreak in the UK have died. And that includes those persons pictured at right. It is very likely that the cases will increase as it can take years to recognize the
disease. Unfortunately, mad cow disease is considered 100% fatal and there is no treatment. Global food distribution systems can have food safety issues as well They have common sources for foods, they have common distribution sites, and they have multiple brands (which we are going to see on the next slide). In other words, if a food (or an ingredient) is contaminated at its source or during processing, it could potentially spread worldwide. We have just seen recently a source of contamination in cumin spice [note added: cumin spices were contaminated]. So cumin spice was accidentally contaminated with peanuts. As you probably already known, peanuts are one of the most common allergies and can result in deaths. So over the last several months, more and more products have been added to this recall because they used the same contaminated cumin. So if you look at the picture on right does this look very familiar to you? This is one of the biggest grocery chains in Japan and it is owned by Walmart Another food trend that has the potential to create food safety issues is the growing interest in locally grown foods. The food industry has a significant impact on the environment as a result of transport of foods over long distances
especially tomatoes. And of course some foods could be intentionally contaminated Locally grown and sold foods frequently "fly under the radar" of the FDA, USDA, and the EPA. So they do not conform to food safety regulations. They are not using the FDA food code, they are not using a HACCP system, and they do not conform to FSMA. Potentially and quite possibly, the agencies could restrict the sale of locally grown foods without compliance to accepted food safety standards. We are going to see where this occurred when an individuals was selling cider at a local food market after having been warned by the FDA that they could not sell cider. Many "local" producers have been found to purchase supermarket foods and re-label them "organic, local, freerange, etc". These foods are considered mislabeled under FDA guidelines and the FDA could restrict their sale. This slide is included to illustrate how a problem could occur if a food seller is circumventing various regulations In 2009 blooms of red tide, which is an algae, caused high levels of toxin to occur in some shellfish in the Gulf of Mexico. We are going to talk about red tide and the algae that causes it when we get to lecture 11. What would have happened if local harvesters were unaware of the potential risks? What if they did fish the areas and sold the fish?
Another concern with food safety is the increases in food allergies As allergy testing procedures improve and media sources report on food allergies, the number of persons claiming food allergy continues to increase. So we are seeing for sure that part of the increase is due to better testing but that can't explain all of it. Currently, failure to label a known allergen is the leading cause of food recalls. That is very very important, anytime you hear that a food is recalled, check and see what the cause is and I think you are going to find that mostly it is allergens. This has led to some changes in food labeling and increased awareness of product labels. New legislation has set very clear guidelines on the labeling of allergens in foods I would like you to take a moment and look at the ingredients label here. How many items can you find on this label that may be hazardous to a consumer's health? Specifically allergens. Allergens were the leading cause of recall on this FDA food recall list As you can see there are a number of different foods and companies involved. But as you go down the list where it says reasons or problems you are going to see that undeclared fish, peanuts, almonds, dairy products, and again peanuts.
