High fructose corn syrup

"HFCS" redirects here. It is not to be confused with HFCs.

High-fructose corn syrup

Nutritional value per 100 g (3.5 oz)
Energy	1,176 kJ (281 kcal)
Carbohydrates	76 g
Dietary fiber	0 g
Fat	0 g
Protein	0 g
Vitamins
Riboflavin (B2)	(2%) 0.019 mg
Niacin (B3)	(0%) 0 mg
Pantothenic acid (B5)	(0%) 0.011 mg
Vitamin B6	(2%) 0.024 mg
Folate (B9)	(0%) 0 μg
Vitamin C	(0%) 0 mg
Minerals
Calcium	(1%) 6 mg
Iron	(3%) 0.42 mg
Magnesium	(1%) 2 mg
Phosphorus	(1%) 4 mg
Potassium	(0%) 0 mg
Sodium	(0%) 2 mg
Zinc	(2%) 0.22 mg
Other constituents
Water	24 g
Shown is for 100 g, roughly 5.25 tbsp.
Units μg = micrograms • mg = milligrams IU = International units
Percentages are roughly approximated using US recommendations for adults. Source: USDA Nutrient Database

Structural formulae of fructose (left) and glucose (right)

High fructose corn syrup (HFCS) (also called glucose-fructose, isoglucose and glucose-fructose syrup) is a sweetener made from corn starch that has been processed by glucose isomerase to convert some of its glucose into fructose. HFCS was first marketed in the early 1970s by the Clinton Corn Processing Company, together with the Japanese research institute where the enzyme was discovered.

HFCS is used worldwide as a sweetener as it is easier to handle than granulated sugar, and since the price of the raw material, corn, is more stable due to government subsidies and a wider worldwide base of production, than sugar cane. Use of HFCS peaked in the late 1990s; demand decreased due to public concern about a possible link between HFCS and metabolic diseases like obesity and diabetes.

The Corn Refiners Association has attempted to counter negative public perceptions by marketing campaigns describing HFCS as "natural" and by attempting to change the name of the product to "corn sugar," which the FDA rejected.

Uses and composition

HFCS is 24% water, the rest mainly fructose and glucose with 0–5% unprocessed glucose oligomers, HFCS 55 (≈55% fructose if water were removed) is mostly used in soft drinks; HFCS 42 is used in beverages, processed foods, cereals, and baked goods. HFCS-90 has some niche uses but mainly mixed with HFCS 42 to make HFCS 55.

Food

In the U.S., HFCS is among the sweeteners that mostly replaced sucrose (table sugar) in the food industry. Factors include production quotas of domestic sugar, import tariff on foreign sugar, and subsidies of U.S. corn, raising the price of sucrose and lowering that of HFCS, making it cheapest for many sweetener applications. The relative sweetness of HFCS 55, used most commonly in soft drinks, is comparable to sucrose.

Because of its superficially similar sugar profile and lower price, HFCS has been used illegally to "stretch" honey. Assays to detect adulteration with HFCA use differential scanning calorimetry and other advanced testing methods.

Beekeeping

Main article: Colony collapse disorder

In apiculture in the United States, HFCS became a sucrose replacement for honey bees starting in the late 1970s. When HFCS is heated to about 45 degrees C, hydroxymethylfurfural can form from the breakdown of fructose, and is toxic to bees. HFCS has been investigated as a possible source of colony collapse disorder.

Production

Corn syrups, including HFCS, are made from corn starch. Commercial production of corn syrup began in 1864. In the late 1950s scientists at Clinton Corn Processing Company in Iowa tried to turn glucose from corn starch into fructose, but the process was not scalable. In 1965-1970 Yoshiyuki Takasaki, at the Japanese National Institute of Advanced Industrial Science and Technology (AIST) developed a heat-stable Xylose isomerase enzyme from yeast, and three years later AIST partnered with the Clinton company to commercialize the process.

In the contemporary process, corn (maize) is milled to produce corn starch and an "acid-enzyme" process is used in which the corn starch solution is acidified to begin breaking up the existing carbohydrates, and then enzymes are added to further metabolize the starch and convert the resulting sugars to fructose. The first enzyme added is alpha-amylase which breaks the long chains down into shorter sugar chains – oligosaccharides. Glucoamylase is mixed in and converts them to glucose; the resulting solution is filtered to remove protein, then using activated carbon, and then demineralized using Ion-exchange resins. The purified solution is then run over immobilized xylose isomerase, which turns the sugars to ~50–52% glucose with some unconverted oligosaccharides, and 42% fructose (HFCS 42), and again demineralized and again purified using activated carbon. Some is processed into HFCS 90 by liquid chromatography, then mixed with HFCS 42 to form HFCS 55. The enzymes used in the process are made by microbial fermentation.

Sweetener consumption patterns

Historical

Prior to the development of the worldwide sugar industry, dietary fructose was limited to only a few items. Milk, meats, and most vegetables, the staples of many early diets, have no fructose, and only 5–10% fructose by weight is found in fruits such as grapes, apples, and blueberries. Molasses and common dried fruits have a content of less than 10% fructose sugar. From 1970 to 2000 there was a 25% increase in "added sugars" in the U.S. After being classified as "generally recognized as safe" (GRAS) by the U.S. Food and Drug Administration in 1976, HFCS began to replace sucrose as the main sweetener of soft drinks in the United States. At the same time, rates of obesity rose. That correlation, in combination with laboratory research and epidemiological studies that suggested a link between consuming large amounts of fructose and changes to various proxy health measures including elevated blood triglycerides, size and type of low-density lipoproteins, uric acid levels, and weight, raised concerns about health effects of HFCS itself.

United States

Consumption of sugar and corn-based sweeteners in the United States from 1966 to 2013, in dry-basis pounds per capita.

In the US, sugar tariffs and quotas keep imported sugar at up to twice the global price since 1797, while subsidies to corn growers cheapen the primary ingredient in HFCS, corn. Industrial users looking for cheaper replacements rapidly adopted HFCS in the 1970s.

HFCS is easier to handle than granulated sucrose, although some sucrose is transported as solution. Unlike sucrose, HFCS cannot be hydrolyzed, but the free fructose in HFCS may produce Hydroxymethylfurfural when stored at high temperatures; these differences are most prominent in acidic beverages. Soft drink makers such as Coca-Cola and Pepsi use sugar in other nations, but switched to HFCS in the U.S. in 1984. Large corporations, such as Archer Daniels Midland, lobby for the continuation of government corn subsidies.

Other countries, including Mexico, typically use sugar in soft drinks. Some Americans seek out Mexican Coca-Cola in ethnic groceries because they prefer the taste compared to Coca-Cola in the U.S. which is made with HFCS. Kosher for Passover Coca-Cola sold in the U.S. around the Jewish holiday also uses sucrose rather than HFCS and is also highly sought after by people who prefer the original taste.

Consumption of HFCS in the U.S. has declined since it peaked at 37.5 lb (17.0 kg) per person in 1999. The average American consumed approximately 27.1 lb (12.3 kg) of HFCS in 2012, versus 39.0 lb (17.7 kg) of refined cane and beet sugar.

European Union

In the European Union (EU), HFCS, known as isoglucose in sugar regime, is subject to a production quota. In 2005, this quota was set at 303,000 tons; in comparison, the EU produced an average of 18.6 million tons of sugar annually between 1999 and 2001.

Japan

In Japan, HFCS is manufactured mostly from imported US corn and the output is regulated by the government. For the period from 2007 to 2012 HFCS had a 27-30% share of the Japanese sweetener market.

Health

Health concerns have been raised about a relationship between HFCS and metabolic disorders, and with regard to manufacturing contaminants.

Obesity and metabolic disorders

Sugars became a health concern among the American public in the early 1970s with the publication of John Yudkin’s book, Pure, White and Deadly, which claimed that simple sugars, an increasingly large part of the Western diet, were dangerous. In the 1980s and 1990s Gerald Reaven and Sheldon Reiser of the USDA published papers discussing the dangers of dietary fructose from consumption of sucrose and of HFCS, especially with regard to heart disease, diabetes, and obesity. These concerns came to the public's attention through media attention to a 2004 commentary in The American Journal of Clinical Nutrition that suggested that the altered metabolism of fructose when compared to glucose may be a factor in increasing obesity rates since, as compared to glucose, fructose may be more readily converted to fat and the sugar causes less of a rise in insulin and leptin, both of which increase feelings of satiety. Fructose, in contrast to glucose, was shown to potently stimulate lipogenesis (creation of fatty acids, for conversion to fat). In subsequent interviews, two of the study's authors stated the article was distorted to place emphasis solely on HFCS when the actual issue was the overconsumption of any type of sugar. While fructose absorption and modification by the intestines and liver does differ from glucose initially, the majority of the fructose molecules are converted to glucose or metabolized into byproducts identical to those produced by glucose metabolism. Consumption of moderate amounts of fructose has also been linked to positive outcomes, including reducing appetite if consumed before a meal, lower blood sugar increases compared to glucose, and (again compared to glucose) delaying exhaustion if consumed during exercise.

In 2007 an expert panel assembled by the University of Maryland's Center for Food, Nutrition and Agriculture Policy reviewed the links between HFCS and obesity and concluded there was no ecological validity in the association between rising body mass indexes (a measure of obesity) and the consumption of HFCS. The panel stated that since the ratio of fructose to glucose had not changed substantially in the United States since the 1960s when HFCS was introduced, the changes in obesity rates were probably not due to HFCS specifically but rather a greater consumption of calories overall, and recommended further research on the topic. In 2009 the American Medical Association published a review article on HFCS and concluded that based on the science available at the time it appeared unlikely that HFCS contributed more to obesity or other health conditions than sucrose, and there was insufficient evidence to suggest warning about or restricting use of HFCS or other fructose-containing sweeteners in foods. The review did report that studies found direct associations between high intakes of fructose and adverse health outcomes, including obesity and the metabolic syndrome.

In 2010, Consumer Reports noted that "HFCS has roughly the same composition as cane sugar—about half glucose and half fructose—and the same number of calories. Concerns that it's directly responsible for rising obesity rates or somehow intrinsically more fat-inducing than sugar are largely unfounded, though researchers continue to study whether the body handles HFCS differently."

Epidemiological research has suggested that the increase in metabolic disorders like obesity and non-alcoholic fatty liver disease, is linked to increased consumption of sugars and/or calories in general, and not due to any special effect of HFCS. A 2012 review found that fructose did not appear to cause weight gain when it replaced other carbohydrates in diets with similar calories. High fructose consumption has been linked to high levels of uric acid in the blood, though this is only thought to be a concern for patients with gout.

Numerous agencies in the United States recommend reducing the consumption of all sugars, including HFCS, without singling it out as presenting extra concerns. The Mayo Clinic cites the American Heart Association's recommendation that women limit the added sugar in their diet to 100 calories a day (~6 teaspoons) and that men limit it to 150 calories a day (~9 teaspoons), noting that there is not enough evidence to support HFCS having more adverse health effects than excess consumption of any other type of sugar. The United States departments of Agriculture and Health and Human Services recommendations for a healthy diet state that consumption of all types of added sugars be reduced.

People with fructose malabsorption should avoid foods containing HFCS.

Manufacturing contaminants

HFCS contains reactive dicarbonyl compounds that are created during the processing steps. These dicarbonyl compounds can in turn create advanced glycation end-products, the possible health effects of which were under investigation as of 2013.

In the contemporary process to make HFCS, an "acid-enzyme" process is used in which the corn starch solution is acidified to begin breaking up the existing carbohydrates, and then enzymes are added to further metabolize the starch and convert the resulting sugars to their constituents of fructose and glucose. A chemical used to separate corn starch from the kernel, lye was formerly manufactured using a process that included mercury, and scientists decided to investigate if HFCS used in food contained mercury. Two papers published in 2009 found that there were traces of inorganic mercury in some foods. However, the mercury was not methylmercury, the form of mercury that is of most concern to human health.

Public relations

Main article: Public relations of high fructose corn syrup

There are various public relations concerns with HFCS, including with its labeling as "natural", with its advertising, with companies that have moved back to sugar, and a proposed name change to "corn sugar". In 2010 the Corn Refiners Association applied to allow HFCS to be renamed "corn sugar", but were rejected by the United States Food and Drug Administration in 2012.

See also

• High maltose corn syrup

Further reading

Litchfield, Ruth (2008). High Fructose Corn Syrup—How sweet it is. Ames, Iowa: Iowa State University Extension and Outreach. Retrieved 2013-03-01. 

External links

• High fructose corn syrup at DMOZ