High-fructose corn syrup

High-fructose corn syrup (HFCS) is any of a group of corn syrups that have undergone enzymatic processing in order to increase their fructose content and are then mixed with pure corn syrup (100% glucose) to reach their final form. The typical types of HFCS are: HFCS 90 (most commonly used in baked goods) which is approximately 90% fructose and 10% glucose; HFCS 55 (most commonly used in soft drinks) which is approximately 55% fructose and 45% glucose; and HFCS 42 (most commonly used in sports drinks) which is approximately 42% fructose and 58% glucose.

The process by which HFCS is produced was first developed by Richard O. Marshall and Earl R. Kooi in 1957 and refined by Japanese researchers in the 1970s. HFCS was rapidly introduced in many processed foods and soft drinks in the US over the period of about 1975–1985.

In terms of sweetness, HFCS 55 is comparable to table sugar (sucrose), which is a disaccharide of fructose and glucose. This makes it useful to manufacturers as a possible substitute for sucrose in soft drinks and other processed foods. HFCS 90 is sweeter than sucrose, while HFCS 42 is not as sweet as sucrose.

Use as a replacement for sugar
Since its introduction, HFCS has begun to replace sugar in various processed foods in the USA. The main reasons for this switch are:
 * HFCS is somewhat cheaper due to the relative abundance of corn, farm subsidies and sugar import tariffs in the United States.
 * HFCS is easier to blend and transport because it is a liquid.
 * HFCS usage leads to products with much longer shelf life.

Cane sugar
Cane sugar is relatively pure sucrose. While the glucose and fructose that are the two components of HFCS are monosaccharides, sucrose is a disaccharide composed of glucose and fructose linked together with a relatively weak glycosidic bond. A molecule of sucrose (with a chemical formula of C12H22O11) can be broken down into a molecule of glucose (C6H12O6) plus a molecule of fructose (also C6H12O6 — an isomer of glucose) in a weakly acidic environment. Sucrose is broken down during digestion into fructose and glucose through hydrolysis by the enzyme sucrase, by which the body regulates the rate of sucrose breakdown. Without this regulation mechanism, the body has less control over the rate of sugar absorption into the bloodstream.

The fact that sucrose is composed of glucose and fructose units chemically bound complicates the comparison between cane sugar and HFCS. The accuracy of saying that sucrose is "composed of 50% glucose and 50% fructose" depends on the context and point of view. Sucrose, glucose and fructose are unique, distinct molecules. Sucrose is broken down into its constituent monosaccharides - namely fructose and glucose - in weakly acidic environments by a process called inversion. This same process occurs in the stomach and in the small intestine during the digestion of sucrose into fructose and glucose. People with sucrase deficiency cannot digest (break down) sucrose, and thus exhibit sucrose intolerance.

Both HFCS and sucrose have approximately 4 kcal per gram of solid if the HFCS is dried; HFCS has approximately 3 kcal per gram in its liquid form.

Honey
Honey is a mixture of different types of sugars, water, and small amounts of other compounds. Honey typically has a fructose/glucose ratio similar to HFCS 55, as well as containing some sucrose and other sugars. Honey, HFCS and sucrose have the same number of calories having approximately 4 kcal per gram of solid; Honey and HFCS both have about 3 kcal per gram in liquid form.

Production
High-fructose corn syrup is produced by milling corn to produce corn starch then processing that corn starch to yield corn syrup that is almost entirely glucose, and then adding enzymes that change the glucose into fructose. The resulting syrup (after enzyme conversion) contains approximately 90% fructose and is HFCS 90. To make the other common forms of HFCS (HFCS 55 and HFCS 42) the HFCS 90 is mixed with 100% glucose corn syrup in the appropriate ratios to form the desired HFCS. The enzyme process that changes the 100% glucose corn syrup into HFCS 90 is as follows: While inexpensive alpha-amylase and glucoamylase are added directly to the slurry and used only once, the more costly glucose-isomerase is packed into columns and the sugar mixture is then passed over it, allowing it to be used repeatedly until it loses its activity. This 42–43% fructose glucose mixture is then subjected to a liquid chromatography step where the fructose is enriched to approximately 90%. The 90% fructose is then back-blended with 42% fructose to achieve a 55% fructose final product. Most manufacturers use carbon absorption for impurity removal. Numerous filtration, ion-exchange and evaporation steps are also part of the overall process.
 * 1) Cornstarch is treated with alpha-amylase to produce shorter chains of sugars called oligosaccharides.
 * 2) Glucoamylase breaks the sugar chains down even further to yield the simple sugar glucose.
 * 3) Glucose isomerase converts glucose to a mixture of about 42% fructose and 50–52% glucose with some other sugars mixed in.

Measuring concentration of HFCS
The units of measurement for sugars including HFCS are degrees Brix (symbol °Bx). Brix is a measurement of the mass ratio of dissolved sugars to water in a liquid. A 25 °Bx solution has 25 grams of sugar per 100 grams of liquid (25% w/w). Or, to put it another way, there are 25 grams of sugar and 75 grams of water in the 100 grams of solution. The Brix measurement was introduced by Antoine Brix.

When an infrared Brix sensor is used, it measures the vibrational frequency of the high-fructose corn syrup molecules, giving a Brix degrees measurement. This will not be the same measurement as Brix degrees using a density or refractive index measurement because it will specifically measure dissolved sugar concentration instead of all dissolved solids. When a refractometer is used, it is correct to report the result as "refractometric dried substance" (RDS). One might speak of a liquid as being 20 °Bx RDS. This is a measure of percent by weight of total dried solids and, although not technically the same as Brix degrees determined through an infrared method, renders an accurate measurement of sucrose content since the majority of dried solids are in fact sucrose. The advent of in-line infrared Brix measurement sensors have made measuring the amount of dissolved HFCS in products economical using a direct measurement. It also gives the possibility of a direct volume/volume measurement.

Recently an isotopic method for quantifying sweeteners derived from corn and sugar cane was developed by Jahren et al. that permits measurement of corn syrup and cane sugar derived sweeteners in humans thus allowing dietary assessment of the intake of these substances relative to total intake.

In the United States


Because of a system of price supports and sugar quotas imposed since May 1982, importing sugar into the United States is prohibitively expensive. High-fructose corn syrup, derived from corn, is more economical since the American price of sugar is artificially far higher than the global price of sugar and the price of #2 corn is artificially low due to both government subsidies and dumping on the market as farmers produce more corn annually. The food industry turned to HFCS as a substitute, with both Coca-Cola and Pepsi switching to HFCS in 1984.

The average American consumed approximately 28.4 kg of HFCS in 2005, versus 26.7 kg of sucrose sugar. In countries where HFCS is not used or rarely used, the sucrose consumption per person can be higher than the USA; for example (2002): Of course, in terms of total sugars consumed, the figures from countries where HFCS is not used should be compared to the sum of the sucrose and HFCS figures from countries where HFCS consumption is significant.
 * USA: 32.4 kg
 * EU: 40.1 kg
 * Brazil: 59.7 kg
 * Australia: 56.2 kg

International markets
In the European Union (EU), HFCS, known as isoglucose, has been subject to production quotas under the sugar regime since 1977. Production of isoglucose in the EU has been limited to 507,000 metric tons, equivalent to about 2%-3% of sugar production. Therefore, wide scale replacement of sugar has not occurred in the EU. In Japan, HFCS consumption accounts for one quarter of total sweetener consumption.

Controversies
Some controversy has arisen over the use of HFCS as a food additive as manufacturers begin to use HFCS in an increasing variety of foods, such as breads, cereals, soft drinks, and condiments.

American farm lobby
The preference for high-fructose corn syrup over cane sugar amongst the vast majority of American food and beverage manufacturers is largely due to U.S. import quotas and tariffs on sugar. These tariffs significantly increase the domestic U.S. price for sugar, forcing Americans to pay more than twice the world price for sugar, making high-fructose corn syrup an attractive substitute in U.S. markets. For instance, soft drink makers like Coca-Cola use sugar internationally but use high-fructose corn syrup in their U.S. products.

Large corporations such as Archer Daniels Midland lobby for the continuation of these subsidies. Since local and federal laws often put a limit on how much money one particular lobbyist can contribute, ADM's contributions are often given by numerous smaller entities under the authority of ADM. This is commonly called bundling political contributions.

Health effects
There are indications that "soda and sweetened drinks are the main source of calories in [the] American diet." Overconsumption of sugars has been linked to adverse health effects, and most of these effects are similar for HFCS and sucrose. There is a striking correlation between the rise of obesity in the US and the use of HFCS for sweetening beverages and foods. The controversy largely comes down to whether this is coincidence or a causal relationship. Some critics of HFCS do not claim that it is any worse than similar quantities of sucrose would be, but rather focus on its prominent role in the overconsumption of sugar, for example encouraging overconsumption through its low cost.

Possible differences in health effects between sucrose and HFCS could arise from the fact that glucose and fructose in sucrose are bound in a disaccharide or from the 10% difference in fructose content. Since many beverages are significantly acidic, sucrose will separate into glucose and fructose which is one of the mechanisms to form an invert sugar. The amount of sucrose converted will depend on the temperature the beverage is kept at and the amount of time it is kept at this temperature.

There are a number of relevant studies published in peer reviewed journals. Studies on the effect of fructose, as reviewed by Elliot et al., implicate increased consumption of fructose (due primarily to the increased consumption of sugars but also partly due to the slightly higher fructose content of HFCS as compared to sucrose) in obesity and insulin resistance. Likewise, the review by Forshee et al. concluded that "HFCS does not appear to contribute to overweight and obesity any differently than do other energy sources."

Melanson et al. concluded that sucrose is metabolized by the body like a mixture of 50% glucose and 50% fructose with no detectable difference from HFCS and Monsivais et al. could detect no difference in the reported satiety levels in people consuming sucrose or HFCS flavoured drinks.

Somewhat related, Sun and Empie found no difference in rates of obesity between people who regularly consume sugar sweetened drinks and those who do not.

Chi-Tang Ho et al found that adding HFCS to fizzy drinks makes them up to 10 times richer in harmful carbonyl compounds, such as methylglyoxal, than those containing cane sugar. Carbonyl compound are elevated in people with diabetes and are blamed for causing diabetic complications such as foot ulcers and eye and nerve damage.

One study concluded that foods with increased pure fructose "produced significantly higher fasting plasma triacylglycerol values than did the glucose diet in men" and "if plasma triacylglycerols are a risk factor for cardiovascular disease, then diets high in fructose may be undesirable". Bantle, et al. "noted the same effects in a study of 14 healthy volunteers who sequentially ate a high-fructose diet and one almost devoid of the sugar."

A study in mice suggests that fructose increases obesity. Large quantities of fructose stimulate the liver to produce triglycerides, promotes glycation of proteins and induces insulin resistance.

Some of the above-referenced studies have addressed fructose specifically, not sweeteners such as HFCS or sucrose that contain fructose in combination with other sugars. Thus, although they indicate that high fructose intake should be avoided, they don't necessarily indicate that HFCS is worse than sucrose intake, except insofar as HFCS contains 10% more fructose. Studies that have compared HFCS to sucrose (as opposed to pure fructose) find that they have essentially identical physiological effects. For instance, Melanson et al (2006), studied the effects of HFCS and sucrose sweetened drinks on blood glucose, insulin, leptin, and ghrelin levels. They found no significant differences in any of these parameters.

Perrigue et al (2006) compared the effects of isocaloric servings of colas sweetened HFCS 45, HFCS 55, sucrose, and aspartame on satiety and subsequent energy intake. They found that all of the drinks with caloric sweeteners produced similar satiety responses, and had the same effects on subsequent energy intake. Taken together with Melanson et al (2006), this study suggests that there is little or no evidence for the hypothesis that HFCS is different from sucrose in its effects on appetite or on metabolic processes involved in fat storage. Both the Perrigue et al study and the Melanson et al study were funded by "the American Beverage Institute and the Corn Refiners Association."

One much-publicized 2004 study found an association between obesity and high HFCS consumption, especially from soft drinks. However, this study did not provide any evidence that this association is causal. In fact, one of the study coauthors, Dr. Barry M. Popkin, is quoted in the New York Times (July 2, 2006, "A Sweetener With a Bad Rap") as saying that “I don't think there should be a perception that high-fructose corn syrup has caused obesity until we know more.” In the same article, Walter Willets, chair of the nutrition department of the Harvard School of Public Health, is quoted as saying that “There's no substantial evidence to support the idea that high-fructose corn syrup is somehow responsible for obesity .... If there was no high-fructose corn syrup, I don't think we would see a change in anything important.” In essence he is saying high-fructose corn syrup is just as bad as other sugars. Willets also recommends drinking water over soft drinks containing sugars or high-fructose corn syrup.

Labeling as "natural"
In May 2006, the Center for Science in the Public Interest (CSPI) threatened to file a lawsuit against Cadbury Schweppes for labeling 7 Up as "All Natural" or "100% Natural", despite containing high-fructose corn syrup. While the US FDA has no definition of "natural", CSPI claims that HFCS is not a “natural” ingredient due to the high level of processing and the use of at least one genetically modifed (GMO) enzyme required to produce it. On January 12, 2007, Cadbury Schweppes agreed to stop calling 7 Up "All Natural". They now call it "100% Natural Flavors".

Snapple (another Cadbury-Schweppes brand) is well-known for being labeled "all-natural," but most varieties contain HFCS. Newman's Own Lemonade and Limeade are labeled as "all-natural" but also contain HFCS. Bread produced by Nature's Own Bread is labeled as having "No artificial preservatives, colors, or flavors," though some varieties contain HFCS. Still, as the FDA has no definition of "natural," in the United States any company may refer to its product as "all natural," regardless of the ingredients.

Taste
Some beverage manufacturers have returned to cane sugar as a sweetener, maintaining that there is a noticeable difference in taste.


 * Jones Soda announced that the company will launch its 12 ounce canned soda (January 2007) sweetened with pure cane sugar instead of high-fructose corn syrup. The brand will be called Jones Pure Cane Soda and will be sold as a 12 ounce can package. As of March 2007, a 12 ounce bottle of Jones Pure Cane Soda Root Beer lists in its ingredients "inverted cane sugar", which seems to mean the same thing as inverted sugar syrup, which, like HFCS, is a mixture of fructose and glucose.


 * Goose Island sodas also use pure sugar and they market this to have a more pure flavor. Their market slogan is "Made with 100% real sugar for better taste."


 * Steaz sodas and energy drinks use only organic cane sugar produced using a "single-crystallization process [which] preserves the original flavor... without the use of additives, preservatives, or animal by-products."

Jolt Cola was originally sweetened with sugar, and marketed with the slogan "All the sugar and twice the caffeine." A later reformulation, though, replaced sugar with HFCS.

Vernors was originally sweetened with stevia from 1866 to 1991 and had a "deliciously different" taste. When the FDA banned stevia in 1991, the company replaced stevia in their drinks with HFCS.

Some Coca-Cola products have started to use sucrose as indicated by the ingredient list clearly marked on the outside of the box. This practice is not widespread and is dependent on individual processing plants. Coca-Cola does not have an official statement at this time on whether they are or are not using sucrose.

One independent Dr Pepper bottler in Dublin, Texas never switched, giving "Dublin Dr Pepper" a unique taste. Other bottlers have since followed suit, sometimes offering both HFCS and cane sugar sweetened versions in the same market.

Blue Sky Beverage Company (a fully-owned subsidiary of the Hansen Beverage Company) has two lines of sodas that do not use HFCS as a sweetener. Blue Sky Real Sugar is a line of sodas that uses sugar as a sweetener, and Blue Sky Organic Sodas use organic cane juice as a sweetener.

Certain soda processing plants, in areas with a large number of adherents of kosher diets, will make sugar-sweetened batches of soda in the spring season for the Jewish Passover holiday. This is because corn and its by-products are considered similar enough to classical grains to be prohibited for use on Passover by Ashkenazic Rabbis.