The Murky World of High-Fructose Corn Syrup

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In the Kitchen with Mother The Murky World of High-Fructose Corn SyrupBy Joyce Forristal, CCP, MTAThink of sugar and you think of sugar cane or beets. Extraction ofsugar from sugar cane spurred the colonization of the New World.Extraction of sugar from beets was developed during the time ofNapoleon so that the French could have sugar in spite of the Englishtrading blockade.Nobody thinks of sugar when they see a field of corn. Most of us wouldbe surprised to learn that the larger percentage of sweeteners used inprocessed food comes from corn, not sugar cane or beets.The process for making the sweetener high fructose corn syrup (HFCS)out of corn was developed in the 1970s. Use of HFCS grew rapidly, fromless than three million short tons in 1980 to almost 8 million shorttons in 1995. During the late 1990s, use of sugar actually declined asit was eclipsed by HFCS. Today Americans consume more HFCS than sugar.High-fructose corn syrup (HFCS) is produced by processing corn starchto yield glucose, and then processing the glucose to produce a highpercentage of fructose. It all sounds rather simple--white cornstarchis turned into crystal clear syrup. However, the process is actuallyvery complicated. Three different enzymes are needed to break downcornstarch, which is composed of chains of glucose molecules of almostinfinite length, into the simple sugars glucose and fructose.First, cornstarch is treated with alpha-amylase to produce shorterchains of sugars called polysaccharides. Alpha-amylase is industriallyproduced by a bacterium, usually Bacillus sp. It is purified and thenshipped to HFCS manufacturers.Next, an enzyme called glucoamylase breaks the sugar chains down evenfurther to yield the simple sugar glucose. Unlike alpha-amylase,glucoamylase is produced by Aspergillus, a fungus, in a fermentationvat where one would likely see little balls of Aspergillus floating onthe top.The third enzyme, glucose-isomerase, is very expensive. It convertsglucose to a mixture of about 42 percent fructose and 50-52 percentglucose with some other sugars mixed in. While alpha-amylase andglucoamylase are added directly to the slurry, priceyglucose-isomerase is packed into columns and the sugar mixture is thenpassed over it. Inexpensive alpha-amylase and glucoamylase are usedonly once, glucose-isomerase is reused until it loses most of itsactivity.There are two more steps involved. First is a liquid chromatographystep that takes the mixture to 90 percent fructose. Finally, this isback-blended with the original mixture to yield a final concentrationof about 55 percent fructose--what the industry calls high fructosecorn syrup.HFCS has the exact same sweetness and taste as an equal amount ofsucrose from cane or beet sugar but it is obviously much morecomplicated to make, involving vats of murky fermenting liquid, fungusand chemical tweaking, all of which take place in one of 16 chemicalplants located in the Corn Belt. Yet in spite of all the specialenzymes required, HFCS is actually cheaper than sugar. It is also veryeasy to transport--it's just piped into tanker trucks. This translatesinto lower costs and higher profits for food producers.The development of the HFCS process came at an opportune time for corngrowers. Refinements of the partial hydrogenation process had made itpossible to get better shortenings and margarines out of soybeans thancorn. HFCS took up the slack as demand for corn oil margarinedeclined. Lysine, an amino acid, can be produced from the corn residueafter the glucose is removed. This is the modus operandi of the foodconglomerates--break down commodities into their basic components andthen put them back together again as processed food.Today HFCS is used to sweeten jams, condiments like ketchup, and softdrinks. It is also a favorite ingredient in many so-called healthfoods. Four companies control 85 percent of the $2.6 billionbusiness--Archer s Midland, Cargill, Staley Manufacturing Co.and CPC International. In the mid-1990s, ADM was the object of an FBIprobe into price fixing of three products--HFCS, citric acid andlysine--and consumers got a glimpse of the murky world of corporatemanipulation.There's a couple of other murky things that consumers should knowabout HFCS. According to a food technology expert, two of the enzymesused, alpha-amylase and glucose-isomerase, are genetically modified tomake them more stable. Enzymes are actually very large proteins andthrough genetic modification specific amino acids in the enzymes arechanged or replaced so the enzyme's "backbone" won't break down orunfold. This allows the industry to get the enzymes to highertemperatures before they become unstable.Consumers trying to avoid genetically modified foods should avoidHFCS. It is almost certainly made from genetically modified corn andthen it is processed with genetically modified enzymes. I've seen someestimates claiming that virtually everything--almost 80 percent--ofwhat we eat today has been genetically modified at some point. Sincethe use of HFCS is so prevalent in processed foods, those figures maybe right.But there's another reason to avoid HFCS. Consumers may think thatbecause it contains fructose--which they associate with fruit, whichis a natural food--that it is healthier than sugar. A team ofinvestigators at the USDA, led by Dr. Meira Field, has discovered thatthis just ain't so.Sucrose is composed of glucose and fructose. When sugar is given torats in high amounts, the rats develop multiple health problems,especially when the rats were deficient in certain nutrients, such ascopper. The researchers wanted to know whether it was the fructose orthe glucose moiety that was causing the problems. So they repeatedtheir studies with two groups of rats, one given high amounts ofglucose and one given high amounts of fructose. The glucose group wasunaffected but the fructose group had disastrous results. The malerats did not reach adulthood. They had anemia, high cholesterol andheart hypertrophy--that means that their hearts enlarged until theyexploded. They also had delayed testicular development. Dr. Fieldexplains that fructose in combination with copper deficiency in thegrowing animal interferes with collagen production. (Copperdeficiency, by the way, is widespread in America.) In a nutshell, thelittle bodies of the rats just fell apart. The females were not soaffected, but they were unable to produce live young."The medical profession thinks fructose is better for diabetics thansugar," says Dr. Field, "but every cell in the body can metabolizeglucose. However, all fructose must be metabolized in the liver. Thelivers of the rats on the high fructose diet looked like the livers ofalcoholics, plugged with fat and cirrhotic."HFCS contains more fructose than sugar and this fructose is moreimmediately available because it is not bound up in sucrose. Since theeffects of fructose are most severe in the growing organism, we needto think carefully about what kind of sweeteners we give to ourchildren. Fruit juices should be strictly avoided--they are very highin fructose--but so should anything with HFCS.Interestingly, although HFCS is used in many products aimed atchildren, it is not used in baby formula, even though it wouldprobably save the manufactueres a few pennies for each can. Do theformula makers know something they aren't telling us? Pretty murky!About the author Forristal, CCP, MTA is the author of Ode to Sucanat (1993) andBulgarian Rhapsody (1998). Visit her website at www.motherlindas.com.