Food science has come a long way since the days of girls taking home economics and boys taking shop class. The classes in my sons’ middle and high schools are now called family and consumer science, or food technology (and both of the boys have taken at least one semester). For simplicity’s sake I will call all such classes food science, because the ultimate aim is to get your students into a career that will support them, and food science is one such. I have written before about food chemistry, big agriculture, and food biotechnology, all of which inform modern food science curricula.

STEM | Food | Economics

A good STEM unit on food science could be developed in conjunction with an economics teacher. A significant percentage of all food globally is imported. In developing countries, the percentage of imported food increases as the country’s income rises. In 2013, there were 13 countries that were 100% dependent on imports for their grain supplies. Importing food may seem like a good economic choice that frees up land for urbanization and population growth, but it leaves a country vulnerable to natural disasters and political changes outside its borders. Russia is one of the world’s largest grain exporters, and it has banned grain exports several times in the last 10 years. Even developed countries are not immune to external disruptions in food supply. In 2009 the United States imported around 16% of all food consumed by its people. In that same year, the United Kingdom imported 50.5% of all its food.

It is important for all students to have some background in food science, because the importance of safe and reliable food sources cannot be overstated. In the United States, the imported and domestic foods we consume sometimes bring food safety issues. The United States Food and Drug Administration (FDA) is nominally responsible for inspecting all food production facilities that supply food for its people. In 2011, there were approximately 130,000 facilities worldwide that the FDA was responsible for inspecting. Food contaminants include foreign materials, chemicals and pesticides, natural toxins, and metals (primarily arsenic, lead, or mercury).

The most common causes of food poisoning in the United States are four strains of bacteria: E. coli, Salmonella, Campylobacter, and Listeria. Campylobacter is most commonly found in poultry and dairy products. The risk of bacterial contamination is much reduced by pasteurization, which is the primary reason most dairy products are treated with this process. Another common method of reducing bacterial contamination in food is irradiation. Thorough cooking of poultry can reduce the risk of contamination from that source. E. coli is well-known for outbreaks associated with ground meat. Listeria has been the cause of outbreaks in consumers of bean sprouts, and peanut butter was the source of a recent outbreak of Salmonella.

Food scientists check the quality of imported food by random sampling at ports. A listing of some of the routine tests performed on imported food samples can be found here. Domestic food is also subject to random sampling. Some of the global standards for microbiological testing of food can be found here. Many food scientists have a background in microbiology or biochemistry, but there are a number of universities that offer undergraduate or graduate degrees in food safety and testing.

Rising costs of domestic meat and produce are another aspect to the climate change theme explored in last month’s post. The increasing frequency of extreme weather events has effects that are expected to continue to impact food costs in the United States. California’s Central Valley produces a third of all the produce consumed by Americans. Right now, the Central Valley is dealing with the prospect of another year of record drought. Farmers are expected to shift their production from animal feed crops to high-value crops like fruits and vegetables. Although this may forestall large increases in produce costs, it will increase the cost of meat. Add in the 2013 drought in the midwestern United States, and beef costs are now as much as 90% higher than they were in 2009.

Do the Math

The math in food choices is a useful topic to explore. An interesting breakdown of the cost of a fast-food burger versus a homemade burger can be found here. Because fast-food burgers benefit from economies of scale, the dollar cost of eating out versus making it at home may be almost the same. But there are intangible costs and benefits to consider, such as the time involved in cooking, which could be spent with your family if you have that time to spend. Eating a home-cooked meal can undoubtedly be less expensive than a fast-food meal, even if it’s not the same meal you would get at a restaurant. The unfortunate reality is that it is not by any means faster, nor in most cases is it better for you. This is why it is important to increase awareness about cooking healthy, fast meals at home. The outreach program called The Food Lab for Kids is a good model for how to do this.

There is increasing evidence for an inverse relationship between the number of meals cooked at home and the obesity rate. There is also a growing environmental movement toward knowing where your food comes from and eating as much locally produced food as possible. Some researchers are also studying how changes in diet affect the gut microbiome. This research has important implications, because evidence is emerging that the gut microbiome plays an important role in human health. In my own opinion, learning to prepare some simple, balanced meals for yourself, from fresh ingredients, should be a life skill everyone has.

If you’d like to incorporate some food science lessons in your classes, some good experiments for high school students can be found here, broken out by whether they have a chemistry or biology focus. A collection of food-themed science fair projects can be found here.

Produced by the National Science Teachers Association (NSTA), science writer Becky Stewart contributes monthly to the Science and STEM Classroom e-newsletter, a forum for ideas and resources that middle and high school teachers need to support science, technology, engineering, and math curricula. If you enjoy these blog posts, follow Becky Stewart on Twitter (@ramenbecky). Fans of the old version of The STEM Classroom e-newsletter can find the archives here.

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