Key Topics
Future Foods
Agricultural biotechnology can be used to develop fresher and better-tasting fruits and vegetables that can help fight disease.
By Milly Ryan-Harshman, PhD, RD
Nutrition Consultant
FEAST Enterprises
"Let food be your medicine and medicine be your food." In 400 BC, Hippocrates could not have imagined that one day agricultural biotechnology could turn his statement into an amazing reality. Agricultural biotechnology research is improving the quality of the food supply and contributing much to the development of a functional foods market.
Four achievements which can be expected are fresher vegetables and fruit, foods with enhanced flavour, foods with reduced allergens and foods that fight disease. Some of the many research projects underway include oils with better fatty acid balance, bananas with better keeping properties, lycopene-enhanced tomatoes, corn with improved vitamin E levels and higher protein soy.
Food Quality
Encouraging people to consume more fresh vegetables and fruit has been a mission of nutritionists for decades. The many kinds of fresh produce available in summer is pleasing to the eye and the palate, but in February, the selection is limited and some products are quite expensive. Even in summer, though, some people hesitate to spend money on fresh vegetables and fruit because they may not keep well.
Fresh, sweet and seedless. Now, using the tools of biotechnology, scientists are working to increase the shelf life of vegetables and fruit, to improve the crispness of carrots, peppers and celery, to develop new seedless varieties of grapes and melons, to improve the sweetness of tomatoes, lettuce, peppers, peas and potatoes, and to extend the seasonal availability of tomatoes, strawberries and raspberries.
Vine-ripened flavour. One area of research that has advanced rapidly is the use of biotechnology to control the ripening of vegetables and fruit. Two substances that are involved in the ripening process are ethylene and polygalacturonase. Ethylene is a plant hormone responsible for the initial phase of ripening; in fact, tomatoes are usually picked green and then ripened artificially using ethylene gas. By controlling the ethylene within the plant through genetic modification, scientists can assure a supply of vine-ripened tomatoes with a longer shelf life. The second substance, polygalacturonase, is a plant enzyme that causes the plant cell walls to break down, thereby softening the vegetable or fruit. Through genetic modification, scientists have slowed down the softening process that leads to overripening by switching off some of the production of polygalacturonase.
Tomatoes were the first fruit to be genetically modified in such ways, but scientists are currently working on bananas, pineapples, peaches, nectarines, papaya, mangoes, strawberries and peppers. By controlling the ripening process, these technologies can also help improve the flavour of produce. Vine-ripened produce naturally has better flavour and this will encourage more people to buy fresh vegetables and fruit.
Hypoallergenic Foods
Although only a small number of people are severely affected by food allergies, food allergy is a serious problem which can cause death. Nearly all food allergies are caused by foods: peanuts, tree nuts, soybeans, milk, eggs, fish, shellfish and wheat. Almost all allergens are proteins; therefore, scientists can alter the genetic makeup of certain foods to eliminate the proteins that cause life-threatening reactions.
On the horizon. Scientists are already working on peanuts, soy and wheat – peanuts are especially important because anaphylactic shock, a condition where a person's organ systems fail, is common in peanut allergy sufferers.
Much progress has already been made with soy. The protein responsible for 65% of all soybean allergies has been identified and a technique called RNA interference has been employed to suppress the genes that code for that protein. Hypoallergenic soy products could be available within 10 years.
Another way in which foods could be made hypoallergenic is to design foods that contain monoclonal antibodies. Monoclonal antibodies can bind to the human body's own antibodies produced by its immune system, thereby eliminating the complexes formed that result in an allergic reaction.
Functional Foods
New food products or "functional foods" may help to reduce risk of chronic diseases such as heart disease and cancer. Functional foods are generally food products eaten as part of the usual diet that have beneficial effects that go beyond what are known as traditional nutritional effects. Today's research will develop functional foods in two ways: new processes using the tools of biotechnology and gene transfers will both be utilized to produce foods with special health benefits.
Health claims. Some of these new foods will carry health claims. Health Canada has approved four claims initially (see box below). As scientific evidence accumulates about the health benefits of certain food components, more health claims may be approved.
- A healthy diet low in saturated and trans fats may reduce the risk of heart disease.
- A healthy diet with adequate calcium and vitamin D, and regular physical activity, may help to achieve strong bones and may reduce the risk of osteoporosis.
- A healthy diet rich in a variety of vegetables and fruit may help reduce the risk of some types of cancer.
- A healthy diet containing foods high in potassium and low in sodium may reduce the risk of high blood pressure, a risk factor for stroke and heart disease.
Healthier oils. A variety of healthier cooking oils are already available to food processors that have special properties. Vegetable oil shortening replaced animal fat (lard) in many baked goods, but shortening has higher levels of trans fat, which is now known to increase blood cholesterol levels. Trans fat is formed when vegetable oils high in polyunsaturated fat are forced to take up hydrogen atoms — a process known as hydrogenation. Using genetic enhancement, researchers have developed a canola oil that is a high oleic, low linolenic acid version with greater stability during frying. This oil can be used by manufacturers rather than lard (high in saturated fat and cholesterol) or vegetable oil shortenings (low in monounsaturated fat and high in trans fat) when frying, potatoes, for example.
Future foods. What's coming to the functional foods marketplace in the near future includes soy beverages with enhanced vitamins and minerals, tailor-made bars and breakfast cereals with added calcium, iron and folic acid, selenium enriched foods to help men fight prostate cancer, and products with antioxidant power. Agricultural biotechnology research will have a significant role to play in this marketplace.
For example, an antioxidant extract from the Saskatoon berry is very powerful, but has a bitter flavour which scientists may be able to remove using the tools of biotechnology. Using these tools may also allow scientists to transfer the omega-6 fatty acid found in borage, a difficult grain to grow, into canola or flax, which also contain ample omega-3 fatty acids. A genetically modified tomato with enhanced levels of lycopene has already been developed, and researchers at the United States Department of Agriculture (USDA) are attempting to increase the ellagic acid content of strawberries. Ellagic acid protects against cancer.
The table below contains some examples of food with special health benefits that plant breeders can experiment with to either enhance their health-promoting substances or transfer those substances to other food products. A wider distribution of lycopene in the food supply, for example, would be a tremendous benefit to those people who are not fond of tomatoes and tomato products, the principle source of lycopene in the Canadian diet. Specialty crops would then be grown in an identity preservation program by farmers to provide people with novel foods to complement their usual diets.
Relief from Menopause Symptoms
- Milk
- Soy
Improvement of Digestive Health
- Honey
- Milk
- Yogurt
- Onions, Leeks, Scallions
- Garlic
Healthy Immune System
- Onions, Leeks, Scallions
- Carrots
Healthy Urinary Tract
- Cranberries
- Blueberries
Cardiovascular Health
- Bananas
- Celery
- Garlic
- Milk, Cheese
- Soy
- Beans
- Fish
- Oats
Stronger Bones
- Milk
- Cheese
- Soy
- Calcium fortified beverage
Antioxidant Power
- Saskatoon berries
- Blueberries
- Cocoa, Chocolate
- Tomatoes
- Green, Black Tea
Cancer Fighters
- Apples
- Grapes
- Citrus fruit
- Tomatoes
- Strawberries
Little did Hippocrates know about what knowledge humans would possess in the 21st century, nor could he even have guessed what life would be like nearly 2,500 years in the future. Today, humans live longer and have harnessed the power of technology to improve their lives. However, one could say Hippocrates predicted the future foods market with stunning accuracy because now, with the advent of biotechnology, humans will no longer grow crops just for food and fibre but also for their special health benefits.
Reading List
- Block G, Patterson B, Subar A. Fruits, vegetables, and cancer prevention: A review of the epidemiological evidence. Nutrition and Cancer 1992;18:1-28.
- Policy Paper: Nutraceuticals/Functional Foods and Health Calims On Foods, Therapeutic Products Programme and the Food Directorate, Health Canada, Ottawa, 1998.
- Functional Foods: Position of the American Dietetic Association. Journal of the American Dietetic Association 1999;99:1278-1285.
- Physiologically active food components. American Journal of Clinical Nutrition 2000;71(suppl):1651S-1742S.
- Raskin I, Ribnicky DM, Komarynytsky S, et al. Plants and human health in the twenty-first century. Trends in Biotechnology 2002;20:522-531.
- Ezzell C. Fixing food: Allergen-free comestibles might be on the way. Scientific American 2002.
- Verrips CT, Warmoeskerken MM, Post JA. General introduction to the importance of genomics in food biotechnology and nutrition. Current Opinion in Biotechnology 2001;12:483-487.