What is candi sugar?

Candy sugar (or “candi” sugar as it is commonly spelled) has a long history in Belgium because of the busy trading port of Antwerp. Until the 19th century, Europe did not produce sucrose, what is now known as table sugar, and relied on sugar imports. According to history about this trade found on Candico’s website, Venetian galleys brought the very first cargoes of cane sugar into Antwerp in 1317. And it is in this area where sugar processing in Belgium turned into a specialized industry serving confectioneries, bakeries, coffee cafés, and, of course, breweries.

There are three forms of candi sugar used by breweries: Rock sugars, free-flowing and semi-soft sugars, and liquid sugars (sometimes called candi syrup). Contrary to basic definitions about candi sugar found scattered around the internet, these are not different forms of the same basic raw material. The solid sugars are the oldest types and are what were produced by Belgian sugarmakers for centuries. Chemically, these products are all based on sucrose from sugar cane or sugar beets (sugar beets are what brought sugar to Europe in the 19th century). Sucrose is a disaccharide made up of glucose and fructose. Unlike maltose, a disaccharide containing two molecules of glucose, sucrose is a non-reducing sugar and is unable to react with amino acids and proteins in the Maillard reaction because the reactive part of glucose that binds with an amino acid in the first step of the Maillard is bound to fructose. This means that when cane and/or beet juice is heated, color development through the Maillard reaction does not happen. This is why colorless sugar crystals can be produced by boiling off sufficient water to result in crystallization.

And this brings us to the first type of candi sugar used by brewers; crystallized cane and/or beet sugar. This type of candi sugar is sold in large, irregular lumps, commonly called rock sugar, or as free-flowing granules. If the latter sounds like common table sugar, it’s because they have the same chemical composition. Colorless candi sugar is a handy ingredient to boost beer ABV without adding other flavors or boosting body from unfermentables. 

Clear rock sugar can be used for the same purpose but is not commonly used by commercial breweries these days because it takes longer to dissolve and is more difficult to handle. Although rock sugar is not commonly used in commercial brewing, many people associate rock sugar, aka rock candy, with candi sugar. Although crystalline candi sugar and rock candy are both forms of sucrose, some candi sugars contain sugars other than sucrose and are colored.

Colored types of candi sugar either contain molasses and/or are processed to allow color development from Maillard and caramelization reactions. Like the Maillard reaction, caramelization is a non-enzymatic browning reaction. But unlike Maillard browning, caramelization does not require amino acids or reducing sugars. In the case of sucrose, caramelization occurs at temperatures above 338 °F (170 °C). If sucrose syrups are acidified and heated, the bond joining glucose to fructose can be broken to form invert sugar. Because glucose is a reducing sugar and able to react with amino acids above certain pH values depending on the amino acid, Maillard reactions are possible. The bottom line is that a wide range of colors and flavors can be made by adjusting process conditions, making candi sugars more than just a clean source of fermentable sugar.

This is where the range of products grows. Caramelized candi sugar tends to crystallize because sucrose solutions that are hot enough to caramelize also contain too little water to remain liquid when cooled. However, when sucrose is “inverted” by acid hydrolysis and then concentrated, liquid candi syrups can be produced because glucose prevents sucrose crystallization upon cooling. Invert sugars can also be cooked to develop color, often after increasing pH, resulting in a wide range of syrup colors. Table 1 shows differences among candi syrups produced by Tiense Suiker in Belgium.

Hopefully that sheds some light onto the ins and outs of candi sugar. It’s definitely an ingredient that is useful in brewing many Belgian beer styles. Picking the right one is up to you.