This post was prepared with the help Carol Harvey, Director of food/nutrition labeling and product development at Palate Works.
If you rely on American supermarkets for your sustenance, then no doubt you have bought and eaten products sweetened with corn syrup. Just look at the ingredient list of bread, cookies, candies, sauces, snack bars, and more to see how prevalent an ingredient corn syrup is.
While sugar, most high fructose corn syrup (aka HFCS – not the same as corn syrup!), agave nectar and other nutritive sweeteners count as 100% “sugars” in the nutrition facts panel, corn syrup elegantly gets away with a limited contribution to the total sugar count in a product.
A serving of sugar is 1 teaspoon. It has 4 grams of Total Carbohydrate, per the nutrition facts label below. All 4 grams of carbs (100% of carbs) are from Sugars.
This, however, is not the case with corn syrup. Below you can see the label for Karo Corn Syrup. A serving is 2 tablespoons, and it contains 30 grams Total Carbohydrate. As a sweetener, you would expect those 30 grams to be coming from Sugars. Alas, only 10 grams, or 33% are Sugars. Where are the other 20 grams?
Here’s a “real world” product example:
Walmart’s butter-flavored syrup pictured above lists corn syrup and HFCS as its two main ingredients. The rest are flavorings and preservatives that don’t add calories or carbs.
The Total Carbohydrate count, 53 grams, is therefore the sum of carbs from the corn syrup and HFCS. But the total Sugars count is only 29 grams, when one would expect it to be 53 grams as well (check any real maple syrup for comparison).
Knowing that Sugars are only one third of the Total Carbohydrate count in corn syrup we can deduce that there are 36 grams of corn syrup used here, and 17 grams of HFCS.
(Mathematically we solved 2 equations for 2 variables:
- x + y = 53
- 0.33x + y = 29
x= corn syrup grams, y = HFCS grams)
Again, the question is – why would corn syrup carb grams be three times as high as their sugar grams? What are those other carbs?
To try and answer the question, we sent a sample of Karo corn syrup to Anresco laboratories for a Sugars Analysis. The results came back within a couple of weeks:
Approximately 13% is dextrose, also known as glucose. This is the simplest form of sugar, a single molecule (monosaccharide), most readily absorbed by our bodies and used for quick energy. Another 12% is maltose, a slightly more complex sugar made from 2 glucose molecules bound together. Maltose is a type of disaccharide. (Another famous disaccharide is sucrose, more commonly known as table sugar. Sucrose is composed of one molecule of glucose and onle molecule of fructose)
We also know that corn syrup is about 25% water (see this USDA data chart). So together with the dextrose and maltose, we have accounted for 50% of corn syrup’s composition.
But what about the other half? Obviously they are carbs. If they were Sugars, then they would need to be labeled as such on the Karo product and in all foods where corn syrup is used. Right?
Stay tuned for tomorrow’s post, where we will explain…
1. Harvard School of Public Health
2. John S. White, Ph.D., President, White Technical Research
3. FDA website