Genetically modified foods or GM foods are foods produced from organisms that have had specific changes introduced into their DNA using the methods of genetic engineering. These techniques allow for the introduction of new traits as well as greater control over traits than previous methods such as selective breeding and mutation breeding. Commercial sale of genetically modified foods began in 1994.
Scientists discovered in 1946 that DNA can transfer between organisms. The first genetically modified plant was produced in 1983, using antibiotic-resistant tobacco. In 1994, the transgenic Flavr Savr tomato was approved by the FDA for marketing in the US. The modification allowed the tomato to delay ripening after picking. In the early 1990s, recombinant chymosin was approved for use in several countries.
In the US in 1995, the following transgenic crops received marketing approval: canola with modified oil composition. In 2000, with the creation of golden rice, scientists genetically modified food to increase its nutrient value for the first time. As of 2011, the US is the leading country in the production of GM foods. Twenty-five GM crops had received regulatory approval. As of 2013, roughly 85% of corn, 91% of soybeans, and 88% of cotton produced in the US are genetically modified.
Foods that include modified DNA and/or protein include fruits, vegetables, corn and soy. Corn and soy are also consumed after modifications that remove most/all DNA/protein.
Fruits and vegetables
Papaya was genetically modified to resist the ringspot. The New York Times stated, "in the early 1990s, Hawaii’s papaya industry was facing disaster because of the deadly papaya ringspot virus. Its single-handed savior was a breed engineered to be resistant to the virus. Without it, the state’s papaya industry would have collapsed.
The New Leaf potato, brought to market by Monsanto in the late 1990s, was developed for the fast food market, but was withdrawn in 2001 after fast food retailers rejected it and food processors ran into export problem
As of 2005, about 13% of the Zucchini (a form of squash) grown in the US was genetically modified to resist three viruses; that strain is also grown in Canada
In 2011, BASF requested the European Union Food Safety Authority's approval for cultivation and marketing of its Fortuna potato as a feed and food. In February 2013, BASF withdrew its application.
In 2013, the USDA approved the import of a GM pineapple that is pink in color and that "overexpresses" a gene derived from tangerines and suppress other genes, increasing production of lycopene.
The plant's flowering cycle was changed to provide for more uniform growth and quality. The fruit "does not have the ability to propagate and persist in the environment once they have been harvested," according to USDA APHIS. According to Del Monte's submission, the pineapples are commercially grown in a "monoculture" that prevents seed production, as the plant's flowers aren't exposed to compatible pollen sources. Importation into Hawaii is banned for plant sanitation reasons
In 2014, the USDA approved a genetically modified potato developed by J.R. Simplot Company, which contains 10 genetic modifications that prevent bruising and produce less acrylamide when fried than conventional potatoes; the modifications do not cause new proteins to be made, but rather prevent proteins from being made, via RNA interference.
In February 2015 Arctic Apples were approved by the USDA, becoming the first genetically modified apple approved for sale in the United States. Gene silencing is used to reduce the expression of polyphenol oxidase (PPO), thus preventing the fruit from browning.
Corn used for food has been genetically modified to tolerate various herbicides and to express a protein from Bacillus thuringiensis (Bt) that kills certain insects. About 90% of the corn grown in the US has been genetically modified. Corn can be processed into grits, meal and flour as an ingredient in pancakes, muffins, doughnuts, breadings and batters, as well as baby foods, meat products, cereals, and some fermented products. Masa flour is variety of flour that is produced using the alkaline-cooked process. A related product, masa dough, can be made using corn flour and water. Masa flour and masa dough are used in the production of taco shells, corn chips, and tortillas.
Genetically modified soybean has been modified to tolerate herbicides, express Bt, and produce healthier oils. About 90% of soybeans in the US are genetically modified. Soybeans contain about 20% oil. In the most common method used to extract the oil, the soybeans are cracked, adjusted for moisture content, rolled into flakes and solvent-extracted with commercial hexane. The remaining soy meal has a 50% soy protein content. The meal is 'toasted' (a misnomer because the heat treatment is with moist steam) and ground in a hammer mill. Ninety-eight percent of the US soybean crop is used for livestock feed. Part of the balance is processed further into high protein soy products that are used in a variety of foods, such as salad dressings, soups, meat analogues, beverage powders, cheeses, nondairy creamer, frozen desserts, whipped topping, infant formulas, breads, breakfast cereals, pastas, and pet foods. Processed soy protein appears in foods mainly in three forms: soy flour, soy protein isolates and soy protein concentrates.
Food-grade soy protein isolate first became available on October 2, 1959 with the opening of Central Soya's edible soy isolate production facility on the Glidden Company industrial site in Chicago.:227–28 Soy protein isolate is a highly refined form of soy protein with a minimum protein content of 90% on a moisture-free basis. It is made from soy meal that has had most of the fats and carbohydrates removed. Soy isolates are mainly used to improve the texture of processed meat products and to increase protein content, enhance moisture retention, and as an emulsifier.
Soy protein concentrate is about 70% soy protein and is basically soybean meal without carbohydrates. Soy protein concentrate retains most of the bean fiber. It is used as a functional or nutritional ingredient in a wide variety of food products, mainly in baked foods, breakfast cereals and in some meat products. Soy protein concentrate is used in meat and poultry products to increase water and fat retention and to improve nutritional values (more protein, less fat).
Soy flour is made by grinding soybeans into a fine powder. It comes in three forms: natural or full-fat (contains natural oils); defatted (oils removed) with 50% protein content and with either high water solubility or low water solubility; and lecithinated (lecithin added). As soy flour is gluten-free, yeast-raised breads made with soy flour are dense in texture. Soy grits are similar to soy flour except the soybeans have been toasted and cracked into coarse pieces. Kinako is a soy flour used in Japanese cuisine.
Textured soy protein (TSP) is made by forming a dough from meal with water in a screw-type extruder, and heating with or without steam. The dough is extruded through a die into various shapes and dried in an oven. The extrusion technology changes the structure of the soy protein, resulting in a fibrous, spongy matrix similar in texture to meat. TSP is used as a low-cost substitute in meat and poultry products.
Corn starch and starch sugars, including syrups
Starch or amylum is a polysaccharide is produced by all green plants as an energy store. Pure starch is a white, tasteless and odourless powder that is insoluble in cold water or alcohol. It consists of two types of molecules: the linear and helical amylose and the branched amylopectin. Depending on the plant, starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight. To make corn starch, corn is steeped for 30 to 48 hours, which ferments it slightly. The germ is separated from the endosperm and those two components are ground separately (still soaked). Next the starch is removed from each by washing. The starch is separated from the corn steep liquor, the cereal germ, the fibers and the corn gluten mostly in hydrocyclones and centrifuges, and then dried. This process is called wet milling and results in pure starch. The products of that pure starch contain no GM DNA or protein.
Starch can be further modified to create modified starch for specific purposes, including creation of many of the sugars in processed foods. They include:
An example of a phosphatidylcholine, a type of phospholipid in lecithin. Red - choline and phosphate group; Black - glycerol; Green - unsaturated fatty acid; Blue - saturated fatty acid
Corn oil and soy oil, already free of protein and DNA, are sources of lecithin, which is widely used in processed foods as an emulsifier. Lecithin is sufficiently processed that protein or DNA from the original crop from which it is derived is often undetectable with standard testing practices. Nonetheless, consumer concerns about GM food extend to such products. This concern led to policy and regulatory changes in Europe in 2000, when Regulation (EC) 50/2000 was passed which required labelling of food containing additives derived from GMOs, including lecithin. Because of the difficulty of detecting the origin of derivatives like lecithin with current testing practices, European regulations require those who wish to sell lecithin in Europe to employ a comprehensive system of Identity preservation (IP).
The US imports 10% of its sugar from other countries, while the remaining 90% is extracted from domestically grown sugar beet and sugarcane. Domestically grown sugar crops come half from beet, and the other half from cane. After deregulation in 2005, glyphosate-resistant sugar beet was extensively adopted in the United States. 95% of beet acres in the US were planted with glyphosate-resistant seed in 2011. Herbicide-tolerant beets are also approved in Australia, Canada, Colombia, EU, Japan, Korea, Mexico, New Zealand, Philippines, Russian Federation and Singapore. The food products of sugar beets are refined sugar and molasses. Pulp from the refining process is used as animal feed. The sugar produced from GM sugarbeets contains no DNA or protein—it is just sucrose, chemically indistinguishable from sugar produced from non-GM sugarbeets.
Most vegetable oil used in the US is produced from GM crops canola, corn, cotton and soybeans. Vegetable oil is sold directly to consumers as cooking oil, shortening and margarine and is used in prepared foods. There is a vanishingly small amount of protein or DNA from the original crop in vegetable oil. Vegetable oil is made of triglycerides extracted from plants or seeds and then refined and may be further processed via hydrogenation to turn liquid oils into solids. The refining process removes all, or nearly all non-triglyceride ingredients.
Adapted from wikipedia
Mark T. Cuatt