High-tech Food. production and explores the related concerned with the incredible advances in food science technology and their careers.

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1 High-tech Food Career and Technical Education Introduction Science in Your Shopping Cart Purpose Background This lesson plan introduces the There really is science in your shopping cart! If we abide by the familiar high-tech aspects of agricultural saying you are what you eat, it is understandable that people may be production and explores the related concerned with the incredible advances in food science technology and their careers. possible impacts on human health. For example, in recent years high-tech scientific processes such as genetic modification, irradiation, and cloning Time: Two or three 45-minute have all been used to increase the safety of the food supply, create foods that sessions are more appealing to eat and easier to produce, and increase crop yields. Level: Secondary This article will summarize a few hot topics in food science, address what is Materials currently known about the safety of these processes, and present resources on the subject to use with your students. Search the e-store page at What are genetically modified foods? Genetically modified (also referred agclassroom.org to find the following to as GM) foods are produced from sources whose genetic makeup has been materials: altered through genetic engineering processes such as recombinant DNA or Science in Your Shopping Cart gene splicing. While this technology is relatively new, if viewed in a historical booklet (PDF) context, people have been selecting desirable plant and animal DNA through Science in Your Shopping Cart traditional selective breeding processes for centuries. PowerPoint Presentation All plant and animal breeding that is selective choosing particular parent Science in Your Shopping Cart stock, plant or animal, and cross-fertilizing (naturally or artificially) to produce video (free download or purchase offspring with desired traits of the parents is, in actuality, low-tech genetic the DVD from the website, 14 engineering. While it is not normally thought of as scientific technology, it min.) provides the foundation for how we have selected the desired traits for our Agricultural Science and food color, taste, size, yield for centuries. Even though humans did not Technology Worksheet, one for have the capacity to isolate DNA until recently, by choosing certain individuals each student for breeding, they were in fact selecting the DNA that would be replicated. Modern Marvels: Harvesting In contrast, newer biotechnology in food production uses gene splicing, Technology video/dvd (order recombinant DNA, cloning, or other techniques to produce the desired online from the History Channel) plant or animal product. With gene splicing and recombinant DNA directly modifying only certain parts of the organisms DNA, it is possible to produce a more consistent product than would be possible using simpler forms of genetic manipulation or selective breeding. The first genetically modified whole food product, a tomato that could be shipped vine-ripened without rotting rapidly, went on the market in Today, the top three genetically modified crops in the United States are soybeans, corn, and cotton. Crops are modified not only for better taste and decreased spoilage, but also for resistance to disease and insects, and tolerance to certain herbicides or pesticides. Manipulating DNA through genetic modification also allows genes from animals to be inserted into plant genomes an example would be inserting the antifreeze protein gene from the Arctic flounder into a tomato s genome to produce a tomato that freezes and thaws better than the traditional tomato. What results is an example of a transgenic plant. Another successful example is the insertion of bacterial DNA that kills certain insects into a plant s genome, thus making the plants pest-resistant. Genetic modification is not limited to the addition of DNA to an organism. Scientists are also genetically modifying the DNA of certain plants to remove or to silence parts of its DNA that cause allergic reactions or gastric distress to those who consume the plants. For example, through gene silencing, researchers were able to alter soybeans so they did not produce a protein Utah Agriculture in the Classroom 1

2 called P34, which causes an allergic reaction in 75 percent of the people allergic to soybeans (Bren 2003). Work is continuing on this technique with soybeans, because there are up to 15 different proteins in soybeans that cause allergic reactions. To be totally effective, scientists will have to determine which of the additional 14 proteins cause allergic reactions and find ways to knock out those proteins as well; it is hoped that within a few years they will be successful. It is estimated that between 70 and 75 percent of all processed foods now available in U.S. grocery stores may contain ingredients from genetically modified plants. Additionally, it must be remembered that genetic modification is not limited to whole foods ingredients may also be engineered. Today, foods such as bread, cereal, hot dogs, pizza, and soda contain genetically engineered ingredients. Genetically modified foods are not required in the United States to carry special labels, unless their content is significantly different from other products of the same type of food (such as decreased nutritional value, added allergen components, and so on). U.S. law requires foods to be labeled with information concerning their material and its processing, not the method by which a plant is developed by a breeder. For example, orange juice that is labeled as fresh orange juice cannot have been subjected to heat or chemical processing or processed into concentrate at any time before sale; the word fresh is considered to refer to the material (contents). Alternatively, if the oranges from which that same orange juice was made were the product of a hybrid cross-fertilization procedure, the orange juice is not required to be labeled hybrid orange juice because hybrid refers not to the contents of the orange juice, but to the method by which the oranges themselves were created. In actuality, almost every product we eat would require special labeling as to the method that was used to produce it if labeling laws extended beyond materials (contents) to include production methods. There are several concerns raised about genetically modified foods. Transgenic plants have received much more attention than transgenic animals, partly because most transgenic animals are usually used for pharmaceutical or research purposes rather than for food. Concerns about genetically modified foods fall into several categories: Environmental Pest-resistant crop plants may kill beneficial insects as well as pests. Another concern is whether the introduced genes will spread from the crop plants into plants growing nearby. For instance, it is proposed that soybeans modified to be resistant to herbicide might cross-pollinate with weeds growing in the fields, thus creating super weeds that would be herbicide-resistant. Economic Transgenic plants are expensive to produce because it takes expensive technology to create them. The companies that produce them (primarily in countries such as the United States) want to make a profit because they put a lot of resources into making them. It is suggested that poor countries that might benefit most from the technology would not be able to afford the seeds. Human health Despite the fact that package labeling for potential allergic reactions is required by law for genetically engineered foods, there is still a concern that allergenic compounds (such as peanuts or soy) may be present in a food eventually consumed by an unknowing allergic person. While a consumer can read labels to control which foods are eaten at home, such control is lost when dining out. For example, a person with a peanut allergy could unknowingly consume a genetically modified food product containing a peanut compound at a restaurant or someone else s home. If the food being consumed normally would not contain peanuts, Utah Agriculture in the Classroom 2

3 there would be no reasonable way for the diner to foresee that consuming it would produce a reaction, and that would place an allergic person at risk (Rajagopal 2001). Activity Procedures Activity 1: Procedures 1. Assign each pair or small group of students one of the products listed on the Agricultural Science and Technology Worksheet. You may want to provide each group with a picture of the product they have been assigned (located on pages 8-12 in this lesson). Alternatively, a real food or nonfood product on the list may be used to add interest. 2. Review the Science in Your Shopping Cart PowerPoint presentation, slides 1-5, and discuss the scientific changes that are sometimes used to change particular crops, animals, and resulting foods. 3. Ask each pair/group to write down, on their Agricultural Science and Technology Worksheet, the scientific changes they think have been applied to the development of the product they have been given (there may be more than one). 4. View with your students the video Science in Your Shopping Cart (streams from the Internet or purchase the DVD). Ask students to write down the actual scientific changes all the products shown in the video have undergone to get that product to the consumer. 5. After viewing the video, ask students if they guessed the scientific changes correctly. Students will notice that not all the products were shown in the video. Provide each group with a copy of the Science in Your Shopping Cart booklet (order or view online) to complete the worksheet. (Utah teachers can order up to 15 free booklets, while they last, from www. agclassroom.org/ut, type shopping cart in the search box and add the item to your cart; be sure to update your quantity.) 6. Show students slides 6 and 7 in the PowerPoint presentation for a few other examples of food science. Activity 2: Procedures Technology is the application of science. To further demonstrate science and technology used in agriculture, view with students the video/dvd Modern Marvels: Harvesting Technology (order online from the History Channel). Students can then complete the last column on the Agricultural Science and Technology Worksheet. This video details harvesting technology for the following: GPS/GIS wheat, cotton, rice, sugar beets, tomatoes, walnuts, olives, lettuce, grapes, and oranges. Activity 3: Procedures Review with students the Concerns About Food Science, the last five slides in the Science in Your Shopping Cart PowerPoint presentation. Here are some questions for discussion: Are the food products safe to eat? Do the benefits of GMO foods outweigh the risks? What is on the horizon in food science? What is left to invent? What are some career opportunities in the area of food science and food technology? How many people have really made a loaf of bread or a gallon of milk? From farm to fork: how much science is in your shopping cart? Utah Agriculture in the Classroom 3

4 Resources/Links Agricultural Biotechnology Questions and Answers pamphlet available from this website: Science and Our Food Supply curriculum and video: and search Food Supply Bringing Biotechnology to Life teacher guide and video: Agricultural Research Magazine: AgroWorld, E-zine and website: Utah Agriculture in the Classroom 4

5 Key to Agricultural Science and Technology Worksheet Agricultural Product Actual scientific changes applied to the development product Harvesting Technology Apples sweeter, crunchier, crisp, enzyme coating to deter browning robotic pickers Carrots more vitamin A, new/old colors, enzyme to enhance color Tomatoes colors, more beta-carotene, longer shelf life for processing thicker-skinned fruit (plant breeding), mechanical harvesting machine that sees color Peaches Pears Watermelon Berries Peanuts new cold tolerant varieties pest resistance disease resistant, improved sweet taste extend the growing season, flavor, thornless varieties lower the fat, but maintain flavor Cayenne Pepper increase the heat by 20% Bread/Wheat Oranges/Citrus Cheese Milk changes in gluten, protein; ability to make sour dough anywhere with the identified bacteria; insect resistance higher yielding trees, increased disease resistance, better color, longer shelf life, freezing technology low-fat cheeses Lactose-free milk bacteria that produces an enzyme that breaks down milk sugar GPS/GIS technology, combine harvesting picking machine, sensors for ripe fruit Grapes seedless varieties, disease resistance, packaging technology mechanized grape moving and picking Potatoes Rice Poultry Beef Oats Corn Soybeans Diapers Cotton Sugar Beets disease resistance, low-fat frying potato doubled the shelf life, rice flour to make bread and reduce oil absorption turkeys bred to have more meat, disease resistance disease prevention, breeding programs for tender, low-fat, flavorful meat reduce cholesterol research enhance corn flavor in tortillas, corn starch, fat replacer, used as a substitute product in lipstick, plastics, flooring, paints, ink, cleaners, etc. cornstarch-based moisture absorber, Super Slurper GPS/GIS technology, combine harvesting cotton picking machine lifter harvester Walnuts stronger trees developed through plant breeding tree shaker Olives better canning methods tree shaker Lettuce lettuce harvester for boxing, precision packing

6 Agricultural Science and Technology Worksheet What scientific changes do we think have been applied to the development of the product we have been assigned? Agricultural Product Apples Actual scientific changes applied to the development of the product Science in Your Shopping Cart (video) Harvesting Technology Modern Marvels: Harvesting Technology (video) Carrots Tomatoes Peaches Pears Watermelon Berries Peanuts Cayenne Pepper Bread/Wheat Oranges/Citrus Cheese over...

7 Agricultural Product Milk Actual scientific changes applied to the development of the product Science in Your Shopping Cart (video) Harvesting Technology Modern Marvels: Harvesting Technology (video) Grapes Potatoes Rice Poultry Beef Oats Corn Soybeans Diapers * * * * * * other food products shown in Modern Marvels: Harvesting Technology

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