Sweeteners in Baking
Sugar in its various forms is the third most used ingredient in the bakeshop, exceeded only by flour and water. The following sections describe the forms of sugar available to bakers, and Table 2 shows the differences in composition of the leading types.
Cube sugar, or lump sugar, is made from the first refined syrup, which is the highest grade. It is formed in moulds while the sugar is still moist, then dried in ovens and packed. Cube sugar is excellent for sugar boiling in caramel work.
Refined granulated sugar is the most common form of sugar used. It is produced in various crystal sizes (fine, super fine, and berry are a few). Custom sizes are also available from some manufacturers, since any size crystal is possible at the factory depending on when the process is halted. The Canadian Food and Drug Regulations require a minimum purity of 99.8% sucrose, but all refined white sugar produced in Canada exceeds 99.9%.
Many food manufacturers purchase granulated sugar in bulk form to save handling and storage costs in their plants. It is delivered in specially designed trucks (20 tonnes) or railway cars (85 tonnes).
Some food manufacturers prefer this mixture of water and sugar. Liquid sugar is metered into the manufacturing process. There are many grades and blends of liquid sugar tailored to suit food manufacturers’ requirements.
When water and sugar are heated in the presence of a weak acid solution and/or enzymes, the sucrose breaks up into sweeteners of simpler chemical structure, creating invert sugar. A similar process occurs in the stomach. Like commercial glucose, invert sugar is a thick, colourless syrup and consists of 38% dextrose, 38% levulose, and 24% water. It is slightly sweeter than sucrose and is popular with some industrial users like soft drink bottlers and confectioners. Invert sugar is a good example of a monosaccharide — that is, despite the presence of a high concentration of sugar, it stays as a thick syrup.
Also known as confectionary or powdered sugar, icing sugar is produced by grinding high-grade crystals. This sugar passes through a series of sieves, yielding a selection of icing sugars. Icing sugar contains from 3% to a maximum of 5% starch (either cornstarch or wheat starch) to retard lumping or crystallization. Tricalcium phosphate may be added in the United States at a level of 1% for the same purpose.
Note: Icing sugar that contains wheat starch is not a gluten-free ingredient!
Fondant sugar is an especially fine icing sugar designed for frostings, doughnut glazes, and cold fondants. One of these super-fine icing sugars comes without any cornstarch, but with a small percent of invert sugar. It is designed for instant fondant centres for chocolate manufacture.
Brown Sugar and Golden (Yellow) Sugar
Brown sugar, light brown sugar, and yellow sugar are refined products containing a molasses-flavoured syrup giving the products a distinctive taste and colour. They are available in a variety of grades and colours and are soft sugars.
Keep this sugar moist. If stored in dry conditions, the sugar becomes lumpy and hard. If the ambient humidity is high, the sugar can be left exposed. If the air is dry, it must be kept well covered.
This is a dark brown sugar containing coarse crystals.
Golden syrup is a by-product of sugar refining. When the syrups, after repeated boiling, no longer yield crystals, the syrup is filtered and concentrated.
Molasses is a by-product of the cane and beet refining processes. Cane sugar molasses is edible and comes in many grades from fancy to black strap molasses. Sugar beet molasses is non-edible but has other industrial uses. Molasses is also available in dry form. In Canada, blackstrap molasses is another name for cooking molasses.
Raw Cane Sugar
This product is imported into Canada in special bulk cargo ships. Conditions under which it is manufactured and shipped vary.
Content of Selected Sugars (simplified)
|Granulated Sugar||Icing Sugar||Invert Sugar||Yellow Sugar|
Table 2 Composition of various sugars
Note: These figures are rounded and may vary depending on place of production.
Sweetness in Sugar
Sweetness is influenced by many factors including temperature, pH, and the presence of other substances that need not themselves be sweeteners. The relative sweetness of sugar and other carbohydrate sweeteners is shown in Table 3. Note that sucrose is the reference standard to which all the other types of sugar are compared. This reference is called the sweetness equivalent.
|Type of Sugar||Sweetness Equivalent|
|Glucose/dextrose||0.74 – 0.80|
Table 3 Relative sweetness of sugars
What this table tells us is that mannitol, for example, is only half as sweet as sucrose. Therefore, two level teaspoons of mannitol would be needed in a cup of coffee to obtain the same sweetness level as one teaspoon of sucrose.