Why is sorbitol in my food?

Abbey
Abbey
Nov 8 · 5 min read

Not to mention chewing gum, toothpaste, and pharmaceuticals too.

One of my closest friends from graduate school spent years studying sorbitol crystallization, and she always took the most beautiful, rainbow-like images of sorbitol crystals under the microscope. Since sorbitol is what brought her into my life, it has always had a soft spot in my heart, although, I think my friend was completely exasperated with the sweetener on a daily basis. I’m sure consumers feel this same irritation when they see a funky word like ‘sorbitol’ on a food’s ingredient statement. So, let me demystify sorbitol and its role in food.

Sorbitol is classified as a sugar alcohol (sometimes called polyols), even though it’s not technically a sugar and definitely not alcoholic. Sorbitol is a sweet carbohydrate that’s lower in calories than any sugar, so it’s often used as an alternative sweetener. Sorbitol is one of many sugar alcohols like mannitol, maltitol, xylitol, erythritol, and lactitol all of which are likely to be found in your food. Each of these compounds differ just slightly in chemical structure, but all are categorized as sugar alcohols.

Sugar alcohols haven’t always been common foods additives but have always been prevalent in nature. A French chemist first discovered sorbitol in the berries of mountain ash trees in 1872 [1]. Mannitol is commonly found in olives, seaweed, and edible fungi. Fermented food products like wine, beer, soy sauce, and sake feature smaller amounts of erythritol, in addition to melons, peaches, and some vegetables.

More recently, sugar alcohols have soared in popularity due to a widespread epidemic of obesity and diabetes in many Western countries. As consumers became more aware of the amount of sugars in their food, manufacturers responded by substituting in something like sorbitol, or another sugar alcohol, to lower the calorie count. Where sugars like sucrose (table sugar) provide 4 Cal/gram, sugar alcohols deliver less energy ranging anywhere between 0.2–2.7 Cal/gram [1].

Beyond the calorie reduction, there are other perks of using a sugar alcohol as a sweetener in foods. First, these compounds are non-cariogenic, meaning they don’t cause cavities in your teeth [2]. Unlike sugar, which microorganisms in your mouth will metabolize into acid that later erodes your teeth, sugar alcohols cannot be used by these microorganisms. In order to make products like mints, gums, and toothpastes more tooth-friendly, traditional sugar has been heavily replaced by sugar alcohols.

A second micrograph of sorbitol crystals. Sorbitol can crystallize into eight different types of crystals, or what is typically called polymorphs.

Sorbitol and other sugar alcohols have also become a massive success since they were the first sweetener used to make sugar-free candies. This transformed sweet treats into diabetic-friendly products as sugar alcohols don’t induce a rise in blood glucose levels. In other words, they can be metabolized without the secretion of insulin.

Another place you might see sugar alcohols sneak into your life is in your pills and other medications. Here sorbitol is used as an ‘excipient’ or a type of material that carries the active ingredient. In most cases, the whole pill is not active medication, instead a sugar alcohol might be added to increase the bulk of the pill. Most commonly, sorbitol, mannitol, and xylitol are used as excipients in the pharmaceutical industry because they help with flowability and binding of ingredients.

Some sugar alcohols have their own special talents that can be taken advantage of in products. Have you ever tossed a mint in your mouth and felt like you were breathing icy, cool air? This is most likely xylitol, which is known for its intense cooling sensation on your mouth and lips. Next time you have the chance, check the label of a minty product like chapstick, chewing gum, or breath mints for the presence of a sugar alcohol.

Lactitol is unique among the sugar alcohols as it’s classified as a prebiotic, or type of fiber. These kinds of compounds are able to survive gastric digestion and migrate into the colon where they are metabolized by beneficial bacteria. They also make you toot, but that’s a good thing since upping the amount of fiber in your diet has been associated with better gut health, lower weight, and lower incidence of cardiovascular disease [3].

There is one MAJOR downside to sugar alcohols and make sure to read on, so you don’t land yourself in the bathroom. You need to be wary of eating sugar alcohols in excessive amounts. Most people can only tolerate up to 50 grams of sorbitol a day [4]. Luckily, most foods only contain about 10 grams of sorbitol per serving, so as long as you don’t go ham on those sugar-free gummy bears, you’ll be fine. If you do overdo the sugar-free candy, you’ll be quick to notice a powerful laxative effect along with flatulence, bloating, and abdominal discomfort. Not a good time!

As mentioned earlier, sugar alcohols are found in nature, but most often they are produced from sugars using a process known as hydrogenation [4]. This is a type of chemical reaction where hydrogen gas is used to add more hydrogen atoms to a compound. For example, if glucose undergoes hydrogenation, and extra hydrogen atoms are added, it then becomes sorbitol. This means the structural differences between sugars and sugar alcohols are actually quite small. They only differ by a couple hydrogen atoms.

I know seeing bizarre looking words like ‘sorbitol’ or ‘xylitol’ on your food’s ingredient statement can be alarming, but I hope to have cleared up some of the misconceptions about these ingredients. Sugar alcohols are rock stars compared to sugar! They don’t cause cavities and contribute a lower number of calories. All this while giving a product a clean, sweet taste.

But seriously, don’t binge any type of food that contains sugar alcohols. It will result in a considerable amount of toilet time. If you don’t believe me, read these reviews of Haribo’s sugar free gummy bears for some real entertainment! https://www.amazon.com/Haribo-SUGAR-Classic-Gummi-Bears/product-reviews/B006J1FBLM

Sources

1. Grembecka, Małgorzata. “Sugar Alcohols — their Role in the Modern World of Sweeteners: A Review.” European Food Research and Technology 241.1 (2015): 1–14.

2. Zumbe, Albert, Adam Lee, and David Storey. “Polyols in Confectionery: The Route to Sugar-free, Reduced Sugar and Reduced Calorie Confectionery.” British Journal of Nutrition 85.S1 (2001): S31–45.

3. Slavin, Joanne. “Fiber and Prebiotics: Mechanisms and Health Benefits.” Nutrients 5.4 (2013): 1417–435.

4. “Sorbitol and Mannitol.” Sweeteners and Sugar Alternatives in Food Technology, by Helen Mitchell, Blackwell Pub., 2006, pp. 249–261.

Food Under a Microscope

Get up close and personal with your food! Learn about the food you eat through beautiful microscopic images with added explanations and fun facts of what you are seeing from a food scientist’s perspective.

Abbey

Written by

Abbey

Food scientist working towards her PhD. Sharer of food structure, processing, nutrition, trends, & history. Disprover of food myths, lies, & misinformation.

Food Under a Microscope

Get up close and personal with your food! Learn about the food you eat through beautiful microscopic images with added explanations and fun facts of what you are seeing from a food scientist’s perspective.

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