What are sweeteners actually made of?
Sweeteners are everywhere. You will find them in soft drinks, chewing gum, desserts, yoghurts, sauces and, of course, plenty of the drinks and snacks found in vending machines. But have you ever stopped to wonder what a sweetener actually is?
The word sweetener sounds as though it describes one particular ingredient, but it is actually a broad term covering a surprisingly varied group of substances. Some come from plants, some are made by modifying naturally occurring sugars and others are produced through carefully controlled chemical processes.
So, what exactly is hiding behind those little sachets and the words on food labels?
Not all sweeteners are the same
The first thing to understand is that sweeteners fall into several different categories.
Some, such as steviol glycosides, originate from plants. Steviol glycosides are extracted from the leaves of the stevia plant, which has been used for its sweet taste for centuries in parts of South America. They can taste hundreds of times sweeter than ordinary table sugar, so only a very small amount is needed.
Others are produced from substances that originally come from sugar or starch.
Sucralose, for example, starts with ordinary sucrose – the same sugar that we put in our tea or coffee. During manufacture, some of the hydrogen and oxygen atoms in the sugar molecule are replaced by chlorine atoms. The resulting compound is extremely sweet, but the body absorbs very little of it.
Then there is aspartame, which is made from two amino acids: aspartic acid and phenylalanine. These are substances that occur naturally in many foods and are also components of proteins. Aspartame is particularly interesting because it is around 200 times sweeter than sucrose, meaning that only a tiny quantity is required.
Saccharin, one of the oldest widely used artificial sweeteners, is quite different. It is a synthetic compound that was discovered accidentally in the late nineteenth century. It is several hundred times sweeter than sugar and has been used in food and drinks for well over a century.
What about acesulfame K?
Another familiar name on ingredient lists is acesulfame potassium, often shortened to acesulfame K or Ace-K.
It is a synthetic sweetening compound that is considerably sweeter than sugar. The potassium in its name refers to the potassium salt form in which it is used. Like several other high-intensity sweeteners, it can be combined with other sweeteners to create a taste profile that more closely resembles sugar.
You may therefore find more than one sweetener in the same drink. This is not necessarily because manufacturers simply want to make something exceptionally sweet. Different sweeteners have different taste characteristics, and combining them can help produce a more rounded flavour.
And then there are polyols
There is another group worth mentioning: polyols, also known as sugar alcohols.
Despite the name, they are neither ordinary sugar nor alcoholic drinks. They include substances such as sorbitol, xylitol and maltitol. They occur naturally in some fruits and vegetables, although the quantities used commercially are generally produced from plant-derived carbohydrates.
Polyols provide fewer calories than sugar and are often used in products such as sugar-free confectionery and chewing gum. They also have the useful property of being less likely than ordinary sugar to contribute to tooth decay.
There is a catch, though. Eating large quantities of some polyols can have a laxative effect, which is why products containing significant amounts may carry a warning.
Why use sweeteners at all?
The main attraction is simple: sweet taste without needing as much sugar.
High-intensity sweeteners can be hundreds of times sweeter than sugar, so only a tiny amount is needed. This allows manufacturers to reduce the amount of sugar in a product while retaining a sweet flavour.
For vending operators, this means there is a wide range of drinks available to suit different tastes and dietary preferences. A vending machine might offer everything from traditional sugar-sweetened drinks to reduced-sugar and sugar-free alternatives.
Are natural sweeteners better?
The word “natural” certainly sounds reassuring, but it does not automatically tell us whether something is better or worse for us.
Stevia, for example, comes from a plant, but the sweetening ingredients used in commercial food products are purified steviol glycosides. Conversely, some synthetic sweeteners have been extensively assessed for their permitted uses.
In the UK, approved food additives, including permitted sweeteners, are subject to safety assessments and maximum permitted levels. The important thing is therefore not simply whether a sweetener sounds natural, but what the ingredient is, how much is consumed and how it is being used.
So next time you pick up a can of sugar-free drink from a vending machine and see a list of unfamiliar ingredients, there is no mysterious substance hiding inside. Depending on the product, that sweetness might have come from a plant, modified sugar, amino acids or a carefully manufactured synthetic compound.
Sweeteners may sound complicated, but their purpose is remarkably straightforward: delivering the sweet taste we enjoy while allowing manufacturers to use considerably less conventional sugar.
