The word sugar is used differently in chemistry and culinary discussions. The word sugar, chemically, can be used to refer to monosaccharides or disaccharides themselves, rather than to refined white sugar and other sugar products. This article concerns “sugar” as the word is commonly used, referring to a refined product or the type of products we commonly refer to as “processed sugar” or “table sugar.” How it table sugar produced? Where does it come from? What are the steps involved?
Where Does Sugar Come From?
Sugar is produced from sugar cane or sugar beets. The most common source, by far, is sugar can, however.
Sugar cane, or Saccharum officinaruma, is tropical grass belonging to the same family of plants as sorghum, Johnson grass, and corn (maize), started being used as a source of sugar thousands of years ago in India, where it was mentioned in writings from 1400 to 1000 B.C. Although no one knows for sure, it is generally accepted that the plant was originally native to New Guinea. Modern sugar cane is a hybrid of several species of the genus Saccharum.
Sugar beets, or Beta vulgaris, which are white rather than red, are another viable sugar crop. They are a much more recent crop for this purpose, having only been introduced as a means for extracting sugar in 1794.
How Are Sugar Cane and Sugar Beets Refined?
Sugar cane is harvested, washed, and then shredded by giant steel rollers, which crush and squeeze the juice from the cane. Water is then sprayed on the crushed plants to get more juice to seep out.
Harvested sugar beets are washed, sliced, and soaked in vats of hot water to extract the sugar juice.
The juice from either plant is then heated in evaporation tanks so that it is concentrated into a thick syrup called molasses. During this process, sugar crystals are induced to form. These crystals can then be separated from the molasses by centrifuge.
After the “raw” sugar crystals are obtained, the sugar is further processed according to the end product being produced, such as white, turbinado, powdered, or brown sugar.
What are the Types of Processed Sugar?
Although most of the sugars mentioned below are produced from sugar cane or sugar beets, there are some other sugars that are sometimes used or have been used, as ingredients in food manufacturing.
Brown Sugar: processed white cane sugar to which molasses has been added. It contains varying amounts of sucrose, caramel, and molasses, all impurities that are originally removed during the refinement of table sugar.
Brown sugar can be anywhere from 85 to 95% pure sucrose, depending on how much molasses is added, which is what determines the difference between the “light brown sugar” and “dark brown sugar” we are familiar with. Yes, it’s a fair guess to say that light brown sugar contains a bit more sucrose than dark brown sugar. But not enough less to make a difference in the diet!
See also Why Does Brown Sugar Dry Out and Harden and What Can I Do About It?
Concentrated Fruit Juice: Used as a sweetener in processed foods, this is a concentrated sugar made from dehydrated and deflavored fruit juice. This sweetener is often used to sweeten products so that they can claim to be “all fruit” or “pure fruit.”
Confectioner’s Sugar: Finely powdered granulated white sucrose sugar. Most confectioner’s sugar for home use has some corn starch, wheat flour, or calcium phosphate added to keep it free-flowing. Also known as icing sugar or frosting sugar.
Corn Syrup: A syrup, synonymous with glucose syrup, made from maize (corn) via either acid or enzyme hydrolysis. This syrup contains glucose and varying levels of polysaccharides, maltodextrins, etc. It can be hydrolyzed to various degrees up to the point of producing pure dextrose (glucose). Corn syrup comes in various strengths (sweetness) which are determined by the amount of hydrolysis and come in “dextrose equivalents” (DE): 24, 36, and 42 DE. The higher the DE the thinner and sweeter the syrup is. The lower the DE the thicker and more starch-like. Corn syrup is one of several types of “starch hydrolysates” that are popular in the food manufacturing industry.
High Fructose Corn Syrup (HFCS): Produced from corn syrup (glucose syrup), some of the glucose is isomerized to fructose by the enzyme glucose isomerase. Although it is possible for HFCS to contain up to 90% fructose, the most common product used contains around 42% fructose, as this most closely resembles sucrose. HFCS is less expensive and sweeter than white sucrose sugar, and so is a popular sweetener of beverages such as soda. In other instances, such as baking, many criteria determine what type of corn syrup, or sweetener will be used.
Honey: A sweet syrup produced from the nectar of flowers by bees as a food source for the hive. Honey is always a mixture of glucose, fructose, a small amount of sucrose, and moisture, with some other sugars and impurities. The composition will vary depending on the flowers the bees used to produce the honey.
A typical batch of honey consists of around 40% fructose, 35% glucose, and 1 to 2% sucrose. Other sugars may include isomaltose, turanose, trehalose, erlose, maltotriose, melezitose, and raffinose, but these are present in only trace amounts of less than one percent. The rest is moisture, minerals, vitamins, beeswax, ash impurities in varying amounts, some enzymes, and aromatic volatile oils, which contribute to the unique flavor. The fructose in honey is sometimes referred to as levulose by the honey industry.
Since many recipes replace granulated sugar with more “healthy” honey, you may wonder what to substitute for the honey should you only have white sugar or some other sweetener.
Invert Sugar: A thin liquid solution of glucose and fructose produced by adding an acid like tartaric acid (cream or tartar) or sucrase (invertase enzyme) to a solution of sucrose (sucrose dissolved in water). The acid hydrolyzes the sucrose, causing it to break down into d-glucose and d-fructose. Sweeter than white granulated sugar, it resists crystallization, making it ideal for professional candy makers who use it to give candy a smooth, melt-in-the-mouth, texture. Invert sugars are an important part of some candy-making processes. See also Candy Making Sugar Stages.
Lactose: Lactose is a natural disaccharide of glucose and galactose. It is the primary carbohydrate found in milk. Lactose is about 1/5 to 1/6 as sweet as sucrose, meaning it barely tastes sweet at all. It is highly prone to crystallization.
The food industry uses lactose, separated from milk, as a browning agent in baked goods and to improve the water-holding capacity of processed meats like ham. It is also used in the making of candies and frozen desserts (besides the natural lactose already found in the milk used to make ice cream, etc.). As an “added” sugar, it does not contribute much to the diet but as a natural sugar, it is found abundantly.
Maltose: Maltose occurs naturally whenever a starch molecule is broken down, whether by a plant to use it’s stored starches as fuel, when seeds are germinating, or when starches are being digested in the intestinal tract. Maltose is used in fermented beverages (beer), breakfast cereals, and some infant formulas.
The maltose used in making beer comes from malt or malt extract, a mix of broken-down starches consisting mainly of maltose. Usually made from barley or wheat, cereal grains are allowed to sprout which causes the enzymatic breakdown (hydrolysis) of the starch to maltose.
Perhaps the most famous occurrence of maltose in prepared food is Post’s “Grape Nuts” cereal, which is made from wheat and malted barley. C.W. Post is said to have mistaken the maltose for glucose (dextrose) which was commonly called “grape sugar” by manufacturers at the time, hence the name Grape Nuts.
Maple Sugar: Produced by boiling maple syrup until most of its water evaporates and the sugar crystallizes. This sugar, like maple syrup, is almost entirely sucrose with only small amounts of free glucose and fructose. It also naturally contains invert sugars. Maple sugar is not commonly used today.
Molasses: Of all the “sugars” molasses can easily lay claim to being the most nutritious. Molasses is what is left over after the sucrose crystals are removed from the concentrated sugar cane (or beet) juice. It is boiled repeatedly to crystallize as much of the sugar as possible until no more sucrose can be extracted. This repeated boiling makes the molasses become darker and darker. The darkness determines the grade, with Blackstrap molasses being the darkest and most bitter.
The amount of sucrose in molasses differs, depending on whether sugar cane or sugar beets were used. Sugar cane molasses contains about 30 to 40% sucrose, some glucose, fructose, and inverted sugar. Sugar beet molasses contains about 60% sucrose. Other components are inorganic salts, and organic acids including amino acids, hemicellulose and pectin fiber, waxes, and ash. You may find molasses products labeled unsulphured, so see Why Does my Mollases say Unsulphured? Was Sulphur Removed From it?.
Raw Sugar: The term “raw sugar” as far as the consumer is concerned, should be considered a marketing joke, as there is no standard definition as to what kind of sugar can be called “raw.” If you wanted to be particular, the word “raw” would mean that virtually no refining of the sugar had taken place.
But this also begs the question of what is “sugar” and what is simply “dried cane juice”. However, most experts would tend to consider raw sugar as sugar that is extracted from sugar cane juice but not refined any further. That is, not washed or decolored. True raw sugar contains dirt, insect parts, yeast, molds, and many other contaminants. As a result, the FDA banned its sale to the public.
However, there are some products sold as raw sugar to consumers, such as “Sugar in the Raw“. These products labeled as raw sugar could be anything, but raw sugars typically are a cruder stage of the sugar production process, before “white sugar” is completely refined.
In the United States, such sugar is called turbinado sugar after the centrifuge in which it is spun. In the U.K. it is called demerara sugar. This sugar has been centrifuged and some of the impurities removed but it retains a light brown, amber color due to the leftover molasses content. It is not truly “raw” however, it is simply partially refined, with a larger crystal size. See Raw or Turbinado Sugar Versus White Sugar.
Sugar alcohols: also known as polyols, sugar alcohols are used in food labeled “sugar-free” and are often referred to as nutritive sweeteners. Chemically, they are saccharide derivatives in which a ketone or aldehyde group has been replaced by a hydroxyl group. These are naturally present, in small amounts, in some fruits and vegetables but they are produced commercially by hydrogenating mono, di, or polysaccharides. They have become popular as a sugar alternative because they are sweet and possess similar properties but deliver less energy, about 1 to 2.5 fewer calories per gram, than sugar. They are absorbed more slowly and less completely by the intestines.
However, this incomplete and slow digestion leads to sugar alcohols being fermented by the intestinal flora. If consumed in excess, they can cause gastrointestinal upset in some people, leading to flatulence, diarrhea, bloating, and other symptoms.
The advantage, in terms of calorie reduction, would appear to be small. Also, there is the problem of the tendency for people to take in more energy from foods that appear to have less calories because of “sugar-free” or other reduced macronutrient labeling. Sugar alcohols do have less of an impact on dental caries (cavities) however because bacteria in the mouth metabolize them much more slowly. This makes them particularly suited to chewing gums, breath mints, or any product that remains in the mouth for long periods.
The sugar alcohols approved for use in the U.S. include erythritol, isomalt, lactitol, maltitol, mannitol, sorbitol, and polyglycitols (hydrogenated starch hydrolysates). Hydrogenated starch hydrolysates or “HSH”, are hydrogenated glucose syrups, maltitol syrups, or sorbitol syrups.
These products are not intensely sweet like many artificial sweeteners such as non-nutritive sweeteners like saccharin, aspartame, and sucralose, also called intense sweeteners. In fact, some of the sugar alcohols are only about half as sweet as sucrose, while others are about as sweet but no sweeter.