In just about every manufacturing industry, whether the products are cars, phones, or foods, it is absolutely essential that finished products meet quality expectations and safety requirements. However, for food, there is another critical requirement – namely, the methods used to validate safety must also be rapid. This is because most foods are perishable and have limited shelf-life. If a microbiological analysis takes five days for an answer before the product can be shipped to retailers, that’s five days of lost shelf-life. Thus, rapid tests that can deliver an answer in a day or less are now widely used.
Note that accuracy and sensitivity cannot be sacrificed for speed. A false negative result (e.g., when the product tests negative for the presence of a pathogen, but the pathogen is actually present) can be disastrous. Likewise, a false positive (e.g., the product tests positive, but it’s really negative) can also be costly.
Most rapid methods, as some of you will learn in the Food Microbiology course, are based on molecular or immunological principles. However, the actual tests are not very complicated, and many are as simple as a home pregnancy test. Others are a bit more technical, but can still be performed by lab techs.
Although Petri plates and test tubes are not going away tomorrow, the day is not too far away when one will simply spot a portion of food on a test strip and an accurate and reliable result will be observable in a minute or two. In fact, for some applications that day is already here. Eventually, I predict there will be smart phone apps that do the same.
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For reasons we will discuss in class, food recalls are now a very common occurrence. As mentioned earlier during the allergens unit, most food recalls are for undeclared allergens (e.g., when soy or milk or wheat or other allergenic ingredients) gets inadvertently added to a food. While these can be serious, the recalls that get the most attention are for pathogens in foods. Even then, unless the recall is particularly widespread and causes lots of illnesses or deaths, it seems like the public hardly pays attention.
Although the FDA and USDA websites post recalls, one of the best sites for a daily check on the most current recalls is the Food Safety News website, maintained by the Bill Marler law firm (Marler Clark). There you can see that since November 1, there were 13 recalls due to pathogenic organisms. Included were Listeria in cheese, green beans and seafood, Salmonella in papayas, E. coli in salad, and Staphylococcus in chicken strips.
For some of these, the contamination was detected before anyone got sick, but in other cases, the recall was prompted by reported illnesses. One might argue that the frequency of recalls is too high and that this means our food supply is not safe. On the other hand, it could also be argued that detection and tracing methods are now so sensitive and so fast that public health is actually better off than ever before.
This a glass half-full or half-empty kind of argument. Which side do you take?
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This is the time of years when the food sections of nearly every newspaper will contain articles on food safety and tips to make sure your holidays are disease-free. No matter, the odds are there will be plenty of day-after stories of people eating undercooked turkey, raw oysters, or some other ill-prepared or contaminated food.
One of the questions we will address is who exactly is responsible for foodborne disease outbreaks. Is it the consumer who may not have followed the instructions? Or is it the manufacturer, processor, restaurant, or retailer who sold contaminated foods? What about the government who is supposed to keep us safe?
Another issue we will discuss concerns the issues of safety and the level of risk we are willing to assume. Can foods ever be 100% safe? What level of exposure is reasonable? If the government said no food (raw or otherwise) could contain any Salmonella or Campylobacter, none of us will be eating turkey next week.
We’ve been talking in class about the bacteria that live in your intestinal tract – how they get there, their role in various diseases, and how to shift the microbial population to promote better health. Of course, before trying to change your gut bacteria, it might help to know what’s actually there. Doing so is not as difficult as you might think. In fact, if you have $99, you can have your gut analyzed and get a profile of your very own microbiota.
So far, more than 6,000 people have joined the “American Gut Project”. It’s very easy to participate – they send you a sample kit, you collect the sample, mail it back, and wait for the results. One has to be careful, however, about interpreting the data. For example, how would you react if you learned you were harboring bacteria associated with particular diseases? Bioethicists are also concerned about privacy issues. Nonetheless, collecting data from thousands of people is great for scientists who are studying the gut.
As noted at the end of Monday’s lecture, there is now a rather unconventional medical practice being used to treat antibiotic-resistant Clostridium difficile infections. This organism, called “C. diff” in the popular press, causes a truly miserable disease. Patients that have this organism in their gut can be chronically ill, with a terrible quality of life. In severe cases, the infection can be so bad that removal of the colon is sometimes the only remedy.
A few years ago, a handful of medical researchers developed a novel idea – why not replace the gut microbiota of these C. difficile patients with gut contents from healthy donors. When I say “gut contents” you should realize that I am referring to poop. Guess what? It works. As a matter of fact, these so-called Fecal Microbiota Transplants (FMT) work great, with success rates of 90% or higher.
Scientists are now creating fecal banks – collections of gut bacteria from donors that can be stored away and used to treat patients without having to round up fresh material. They are like blood banks. There are even “do-it-yourself” kits and with websites that have detailed instructions. So popular is this treatment, it’s been described in magazines and books.
Films about foods and beverages have long been popular, in part because of how familiar the subjects are to film-goers. Of course, there are documentary and non-documentary films, with many of the latter actually about something other than food. Some of my favorites include:
Sideways, a buddy movie, a road movie, and a love story, all told while the protagonists make their way through the California wineries and restaurants.
Julie and Julia, a past and present film about the famous TV chef, Julia Child.
Waitress, a movie about love, marriage, and pies.
Chocolat (needs no further description!)
Chef, Big Night, and The Hundred-Foot Journey are great movies about restaurants and chefs.
There are also plenty of provocative documentary films about food. Many have an obvious political viewpoint (like Fed Up, Food Inc., and Supersize Me). It’s important to watch these films with a critical eye, as there are many counter-arguments that can be made contrary to the views of the film-maker.
In any event, I imagine you have your own list of favorite movies about food. Yes?
Think of all of the contemporary issues in food science, and GMOs are probably at the top of the list. Here in America’s farm belt, genetically modified (GM) agricultural crops like corn and soybeans are as common as, well, as common as a Nebraska cornfield. Of course, when corn and soybeans are GM, the hundreds or thousands of food products and food ingredients made from those commodities are also GM.
Needless to say, there are a considerable number of consumers opposed to GM technology. While most consumers have gone happily on their way eating these products, others have sought out GMO-free products. This has led to an entire market devoted to non-GMO foods. New labeling laws for identifying GM and non-GM foods will eventually go into effect.
As we discuss the GMO issue, it is important to take the emotion out of the discussion and focus on the science. In the meantime, I encourage you to attend the Evolution of Food film on Tuesday evening at 6:30 in the Ross Theater.
I know we have already covered the obesity topic, but the CDC just released their obesity report for 2016 and the news is bad, really bad. Instead of reducing the adult obesity rate, its actually increased – up to nearly 40%. For middle-aged adults, its above 40%. Time to go back to the drawing board and come up with some fresh ideas, because whatever we’ve tried to slow down this trend is clearly not working.