By Benjamin Raymond
While there are hundreds of different types of sugars, there are only a few that are of much importance for use as sweeteners in foods. All sugars are made of the elements carbon, hydrogen, and oxygen. These elements are formed into a ring structure. Nutritionists and food scientists may refer to sugars as mono-, di-, oligo-, poly-saccharides or sugars.
Monosaccharides are the simplest of sugars and are all composed of one single molecule such as fructose or glucose. Disaccharides are composed of two monosaccharides that have been bonded together, such as lactose (glucose+galactose). Oligosaccharides combine a few different sugars (from the Greek “oligos,” meaning a few). Fructo-oligosaccharides, for example, are found in many vegetables and consist of short chains of fructose molecules.
Starches are polysaccharides composed of hundreds or thousands of glucose units bonded together. tarches do not lend sweetness to foods as the complex and large structure does not trigger sensations of sweetness on the tongue.
Sugars are added to foods not only to add sweetness, but they also contribute to texture and structure, and may aide in preservation. Sugars typically contribute 4 kcals of energy per gram. When consumed, sugars and non-fiber starches are broken down into monosaccharides in the stomach and small intestine by stomach acid and enzymes respectively. They are then absorbed into the bloodstream and may be used for energy or stored in the form of fats or glycogen. Put simply, extra sugar will be stored for use at a later time in the form of fat. Humans cannot break down some polysaccharides and these constitute the fiber portion of ones diet.
There are other molecules found in nature called sugar alcohols that are similar to sugars, but have a slightly different structure. These are not alcohol in sense that they will intoxicate; rather they have “alcohol groups” on the sugar ring structure that effect the way we taste and digest them. These are typically not digested as efficiently as sugar and contribute less calories per gram than sugars such as sucrose. They are usually less sweet than sucrose and are often used to contribute bulk and body to foods that contain high intensity artificial sweeteners. They are also often used in foods such as chewing gum. Bacteria that may contribute to tooth decay aren’t able to digest the sugar alcohols so they do not produce damaging acids. Sugar alcohols are not digested by the body, however, so if large amounts are consumed, bacteria in the large intestine may ferment the sugar alcohols producing gas and intestinal discomfort.
High intensity artificial sweeteners contribute much more sweetness than any of the sugars. They are often hundreds to thousands of times more sweet than sucrose. There are a variety of high intensity sweeteners. The FDA has approved a total of six high intensity artificial sweeteners as Generally Regarded As Safe (GRAS). They are advantame, saccharin, aspartame, acesulfame potassium, sucralose, and neotame. They do not contribute calories to the food they are used in and do not raise blood sugar levels. There are limits to the amount contained in serving of food to ensure they may be safely consumed. In addition to these, there are new nature derived high intensity sweeteners appearing on the market such as stevia and monk fruit extracts that are also much sweeter than sugar.
How to identify the sugar or sweetener in foods? A simple way to determine if an ingredient is a caloric sweetener is to look at the suffix. Ingredient names ending in “ose” such as glucose, lactose, and fructose are sugars that contribute calories to the food. Those ending in “ol” are sugar alcohols and contribute very few, if any calories to the food. Then there are the six high intensity artificial sweeteners (advantame, saccharin, aspartame, acesulfame potassium, sucralose, and neotame) these do not contribute any calories to a food. The natural extracts are often branded products and identified as such. So what does this all mean? Foods that are heavily sweetened with sugars or high intensity sweeteners should be eaten in moderation and not constitute a large portion of one’s daily caloric intake.
Benjamin Raymond was raised in Shrewsbury, Vt, graduated from Mill River High School and then UVM with BS in Nutrition and Food Science and NC State with an MS in Food Science. Raymont is currently employed as an innovation scientist developing new natural food colors in Louisville, KY.