Ingredient Information

Function

Corn syrup is a liquid sweetener derived from corn and is commonly used in processed foods. It is less sweet than cane sugar (table sugar or sucrose) and is available in three different sweetness levels or dextrose equivalent (DE) ratings. The level of sweetness determines the ingredient function and foods that it can be used in.

Corn syrup is used as a humectant and it functions to retain moisture in baked products. This in turns extends the shelf life of many baked goods. It is also recognized as a browning agent, giving bread and crackers their appealing golden brown color when baked. Frozen food products also benefit from the addition of corn syrup. It is known to help prevent or reduce crystal formation by lowering the freezing point of the food in addition to adding sweetness. This function also helps frozen foods thaw faster, an added convenience for the consumer. Corn syrup is also added as a thickener as it adds texture and mouth-feel to many processed foods.

Corn syrup is not the same as high fructose corn syrup, although they share some of the same ingredient functions. High fructose corn syrup differs from corn syrup in that it is sweeter and is more soluble. It is manufactured from corn starch; however an additional enzyme is added to convert some of the glucose to fructose.

Other Use and Industries

Corn syrup is used in the pharmaceutical industry as a flavoring for cough syrups and antacids. It serves as a delivery aid for unpleasant tasting medications. It is also the main ingredient in throat lozenges and can be used in coating of vitamins and tablets. In the tobacco industry, corn syrup is used in the curing process. In the leather tanning process, corn syrup is applied to give the leather a shiny appearance. It also makes the leather soft and pliable.

Health Effects

Consumers are increasingly more aware of the negative effects of consuming too much sugar. Although, not under as much fire as high fructose corn syrup, research is showing that both products are metabolized by the body in the same way. Others tout that fructose is the “bad sugar” and corn syrup, containing only glucose molecules, is safer. Whichever side you fall on, over consumption of refined sugars is unhealthy. Over consumption of refined sugars has been implicated as a causative agent of weight gain, obesity, dental cavities, metabolic syndrome, increased triglyceride levels, diabetes, chronic inflammation, and non-alcoholic fatty liver disease. However, these studies are often criticized. In regards to obesity, scientists believe that there are many other factors, such as lack of exercise and fat consumption play a role in obesity.

The food industry is reacting to the negative perception of corn sweeteners. The consumption of products containing corn-type sweeteners is declining. The corn industry has even petitioned the FDA to allow new names for some refined corn sweeteners. At this time, the FDA has not allowed this change. Regardless, many food companies are removing corn-type sweeteners from their formulations and switching to cane sugar.

In addition, another knock against corn syrup is that it most probably originates from genetically modified corn or GMO corn. Currently, 86% of the US corn crop is genetically modified. Specifically, corn has been genetically altered to resist certain herbicides. Other modifications include insect resistance and vitamin-enriched varieties. Many criticize that these genetic modifications were not tested thoroughly. Others demand that GMO corn ingredients should be labeled so that consumers can make an informed choice about consuming such products. Recent studies are not showing good support of GMO products. One study revealed that GMO corn caused organ damage when fed to rats. If GMO corn is an issue for your beliefs, there are non-GMO corn products available at health foods markets.

Origins

Corn syrup or glucose syrup is a product of the wet milling processing of corn. First, shelled corn is cleaned and placed in large steep tanks. The corn is soaked for 30-50 hours at 130 °F in a dilute solution of sulfur dioxide. This steeping process softens the corn kernel so the germ can be removed. The next step involves the removal of the bran fraction of the kernel leaving the endosperm.

The endosperm consists of mostly starch and some gluten. A centrifugational step is used to separate these two components. Corn starch makes up the remaining fraction and this starch milk is refined and purified by additional centrifugation steps. The corn starch is partially hydrolyzed with two different enzymes to produce corn syrup. The first enzyme, amylase, breaks down the starch into shorter glucose chains. A second enzyme, glucoamylase, further breaks down the starch molecule into glucose molecules. The viscosity and the sweetness of the corn syrup are determined by the degree of hydrolysis during the enzyme process.