Sugar! Without it there would be no chocolate, cakes or diversion from the afternoon meltdown-nothing exciting to eat with a coffee! Sugar is a wondrous ingredient that is used in a myriad of ways. This guide will attempt to answer several questions, such as... Just how do all the different types of sugars and syrups that we have on our shelves at the Essential Ingredient work in cooking? Can I substitute one for another? What is the difference between molasses and treacle, golden syrup and honey? To understand sugar's role in cooking it helps to take a small detour into science so we can break it down into its basic parts.

Sugars are the simplest forms of carbohydrates, also known as saccharides. Sugars can be monosaccharides (mono meaning a single sugar molecule), which are the most basic building blocks of carbohydrates, and disaccharides (di meaning double), which are simply two monosaccharides bonded together. Our body actually breaks down almost everything we eat into these sugars, which are then combined to form more complex carbohydrates like starch. These complex carbohydrates, made up of long chains of sugars, are called polysaccharides and are generally no longer sweet.

What does this all mean? Well, it means that natural sugars are present in many foods and there are many different types of sugar which vary in sweetness. For example the sweetness of honey and golden syrup is quite different to the sweetness of brown sugar, because they differ in chemical composition. This difference in composition also causes different sugars to act differently when cooked or baked, and will result in different levels of sweetness or a finished product that may brown easily or have a crumbly texture.

Glucose is a monosaccharide and is less sweet than other sugars. Fructose, on the other hand, is the sweetest known monosaccharide. Sucrose, or common sugar, has 1 part glucose and 1 part fructose. Sometimes knowing what parts certain sugars or syrups break down into can help when choosing a substitute.

How is sugar made?

Making sugar is a process that begins with boiling juice from the plants with lime (calcium oxide), which partially purifies and clarifies the syrup. The syrup is then evaporated and concentrated and subsequently put into a centrifuge to draw off more liquid (molasses). The raw sugar is then dissolved again and stripped of colour, filtered and re-crystallized to granulated sugar. A further crystallization occurs to produce granules of specific sizes.

There are many varieties of sugar and despite their similarities they aren't all interchangeable. Here's a quick guide to the most common types of sugar.

Common Sugar

This is your everyday white table sugar. It has a large variety of uses, which we won't go into in this guide for the sake of brevity! Normal granulated sugar has a grain size of about 0.5mm across. You can also get larger grained sugars such as hail sugar which is popular for decorating cookies and other deserts.

Caster Sugar

Caster sugar is preferred in pastry and cake making as the granules are finer (around 0.35mm) and dissolve faster. With more sharp edges to cut through fat, batters become aerated more rapidly. Caster sugar also dissolves into beaten eggs for meringue with greater efficiency, and it's worthwhile to know that table sugar will typically produce a cake with a speckled crust.

A small note on etymology, the term caster or castor sugar is a British term given to sugar fine enough to fit through a sugar "caster" or sprinkler. In the United States this sugar is also sold as "superfine" sugar.

Icing Sugar (or confectioners sugar)

This is crushed, powdered granulated sugar. It is used in icings, fillings and some pastries, such as friandes and sable. It's also one of the most important ingredients in cake decorating. This is because icing sugar is the basis of royal icing, which is used for decorating and writing, and it's also used to make "cake glue" and to dust surfaces before rolling out icings.

There are a few different sorts of icing sugar and they are not interchangeable. Pure Icing Sugar is pure unmixed sugar with no additives. Pure icing sugar is quite lumpy and usually needs to be sifted. This is the sugar used for Royal icing. Icing Sugar Mixture is sugar that has been blended with a small amount of cornflour (around 4%). It's not so good for cake decorating work as the small amounts of flour present can start to form mould if there is any moisture in the cake or decorated items (and there usually is). Pure sugar will not mould. Icing sugar mixture however is fantastic for making simple glazes and icings, and fillings where a small amount of cornflour will not effect the result. It does not clump or lump and this is a definite advantage. Snow Sugar is icing sugar with a mixture of cornflour and a touch of vegetable fat and dextrose. This mixture produces a sugar that doesn't melt when dusted onto cakes and tarts. This is its primary use, although I have spoken to customers who bake with it very successfully.

Palm Sugar

Comes from a sugar-giving tree of which there are several. The most generous is the Asian sugar palm. The sap is collected from the flowers or from a tap in the trunk then boiled down to syrup (called palm honey) or crystallized to a mass. The dark sugar is often called jaggery and has a distinct almost winey aroma. It is mostly used in Indian, Indonesian and some African cuisines. A lighter palm sugar is also used extensively in Thai cuisine. This lighter palm sugar is the most common palm sugar used in our kitchens in Australia.

Brown Sugar

Brown sugars are softer and moister than granulated sugars. Their crystals are coated with a molasses like syrup. Darker sugars are more intensely flavoured, as the colour relates to the molasses retention. Glucose and fructose are present in the molasses syrup coating the crystals. These attract and retain more moisture in the sugar itself, making brown sugars great for baking, as the products will retain more moisture and stay fresher for longer periods. Granulated sugars are 99% sucrose and brown sugars vary between 85-92% sucrose along with glucose and fructose. If brown sugar is used instead of granulated sugar the result will be more flavourful and moist but the browning temperature will be lower. Demerara sugar can also be in this category, as it often comes from the first crystallization of cane juice, producing yellow gold crystals that are frequently washed with alcohol to make them shiny and clear. Muscavado sugars are the crystallization of the dark mother syrup forming very small sticky intensely flavoured sugars.

Invert Sugar

Invert sugar is made from a sucrose water solution (basic sugar syrup) that is heated with the addition of acid. Although invert sugar naturally occurrs in honey, molasses and corn syrup, to name a few, it can also be purchased as a paste or syrup. It doesn't crystallize and it retains moisture. It is sweeter than sucrose (standard sugar), and when added to baked goods it will keep them moist longer. It also helps prevent ice formation in ice creams and sorbets. Therefore, it is used extensively in ice cream, sorbet, glazes and sauces, fondant and candy making. Fudge and caramel sauce are two examples where a non-grainy texture is important.

To make invert sugar, simply boil 3 parts sugar with 1 part water (by weight) and add an acid. For example, add 3kg sugar to 1litre (or kg) water and approx 3-5g of citric acid. Bring this to the boil, strain and cool.

When sugar is dissolved in water it becomes a syrup. Syrups can be used in many situations where crystallized sugar isn't ideal, most notably when sweetness isn't the cause for adding sugar.

Molasses (also known as treacle)

There are a number of grades of molasses. The darker the molasses, the more bitter it is. Blackstrap molasses is usually the last extracted and is very dark as its sugars have been caramelized over and over and an effort to extract as much sucrose as possible. Most of the syrups available as molasses (or treacle) are a blend of molasses in various stages of caramelization and sugar syrups. This is so the molasses can be sold in an almost uniform condition. Just out of interest molasses is approximately 35-50% sucrose, 15-30% invert sugar and 20-25% water. Molasses is generally added to a recipe for colour and flavour and moisture, rather than sweetness. This is why you will often come across recipes that use molasses or treacle with sugar also added. A good example is gingerbread. Molasses is common in licorice, baked beans, and barbeque sauce. Molasses and to a lesser extent brown sugars are variably acidic, which makes them work well with bi-carbonate of soda as a levening agent.

Golden Syrup

This is refinery syrup made from raw sugar filtered through charcoal to give it a clear appearance and delicate flavour.

Honey

As mentioned before, honey is great for longevity in baked goods. It is very high in fructose and glucose, and is quite similar to invert sugar. It is approximately 1¼ times as sweet as granulated sugar. Heating honey makes it less liable to crystallize as it sometimes does. The sweetness of fructose is registered almost immediately on the tongue, and fades very quickly. This quick action is said to enhance the flavours in some foods, especially fruitiness, tartness and spiciness without the sweetness lingering long enough to mask the flavour of these foods. This is why honey and lemon work so well or honey used in a spicy marinade.

Maple Syrup and Maple Sugar

Maple syrup originates from the sap of the maple tree. The season for harvesting maple sap is very short at approximately six weeks. The water in the sap is separated from the sugars and boiled down, leaving heavily flavoured syrup. It takes about 40 parts sap to make 1 part syrup. After the refining process, the final composition is about 62% sucrose, 34% water, 3% glucose, fructose, and .5% acids. Maple syrup is graded by colour, flavour and sugar content, grade A being the highest grade. The lower darker grade syrups are used in baked goods and glazes. Cheap maple flavoured syrups are usually not maple at all, they're usually corn syrup with maple flavour added. Maple sugar is made by concentrating (boiling) the sap down for much longer than is needed to make the syrup until all that's left is a solid sugar.

Glucose (also known as dextrose)

Glucose is the building block of sugars, a place from which sugar chains are started. It is found in fruits and honey, amongst other things. Glucose is less sweet than granulated sugar. It is less water soluble, producing a thinner solution. It melts and starts to caramelize at 150°C, where granulated sugar will caramelize at around 170°C. It is great for sugar work as it caramelizes more quickly than other sugars. Used in toffees, candies and icecreams, it can keep the product soft and gooey while still caramelizing and setting.

Corn Syrup

Corn is the second largest sugar producing crop. Corn syrup begins as a starchy liquid that is converted into sugars by the addition of acid. The thickness of corn syrup is due to the large number of carbohydrate molecules that are tangled up with each other. This results in a syrup that is much thicker than a standard sugar can produce. Due to the tangled nature of its molecular composition, corn syrup has the valuable effect of preventing other sugars from crystallizing and producing a grainy texture. This means that it helps minimize the size of ice crystals in ice cream encouraging a creamy consistency. Its viscosity helps impart a thick chewy texture to foods. It is less sweet than sugar because it contains a lot of glucose, giving keeping qualities and preventing moisture loss without being overbearingly sweet. Corn syrup is acidic, due to the way it is produced; therefore, it works well with baking soda. Light corn syrup is a mixture of regular and high fructose corn syrup with the addition of vanilla. It contains around 75% fructose plus glucose making the sweetness similar to table sugar. The combination enhances the moisture and develops colour in baked goods. Dark Corn Syrup is a mixture of corn syrup and refiner's syrup, used for colour and flavour.

Date Syrup

This is made from date solids in a solution of sugar. Brands vary but can be a mix of approximately 37% solids with the remaining 63% being a mixture of glucose, fructose, and water.

Grape Syrup

A lovely syrup made from concentrated grape juice containing fructose and glucose, not unlike date syrup.

Sugar is an essential ingredient in many baked goods, but not necessarily for its sweet taste. It has many unique and useful properties which make it an absolute necessity for all kinds of recipes, from croissants to sourdough bread! So how is sugar used in baking, and how does it work?

Colouring

Sugar of any kind will contribute to browning in the oven as it caramelizes. A small amount of milk or milk powder can improve crust colour in bread. Glucose and fructose brown at a lower temperature than other sugars, so ingredients like honey and corn syrup will produce a darker product than other sugars would if used in the same recipe.

Aeration

Creaming is the most effective way to guarantee a light, evenly textured product. During creaming the sharp edges of the sugar crystals cut through the fat and leave air pockets. Caster sugar has more sharp edges than granulated sugar because the crystals are finer. Icing sugar, however, is relatively ineffective for creaming because it is too fine and dissolves too quickly. The addition of chemicals or leveners such as baking powder expands the air bubbles.

Tenderness

In batter and dough sugar competes with starches and protein in flour for available water. This in turn interferes with gluten formation, tenderizing and 'shortening' the product.

Moisture Retention

Sugar in baked goods helps them retain moisture. A roll made with sugar will stay fresh longer than without. This is even more apparent with products made with sugars containing fructose (corn syrup or honey). These goods have superior keeping qualities. Cakes made from honey or molasses such as gingerbread have amazing keeping qualities, the hydroscopic (water attracting) qualities of sugar, particularly fructose is accentuated on a rainy or humid day. This is detrimental to candy making or sugar work. As the goods cool, the sugars attract moisture from the air, causing hard toffee to become sticky and gooey.

Egg, Foams and Structure

Sugar when beaten with eggs or egg whites dissolves, melting into the egg where it absorbs moisture and helps prevent weeping. This makes the whipped egg foam more stable. Sugar also raises the coagulation temperature of eggs this means the batter has more time to rise before it sets.

Spread

Sugar contributes to batter spread. It is most noticeable when cooking dough as the sugar melts it turns to liquid before setting with the other ingredients.

Fermentation

Sugar assists in yeast fermentation. Yeast will consume the sugars in a dough or batter before breaking down other ingredients. Too much sugar will have the opposite effect.

Icing and Glazes

Icings, glazes and frostings don't just taste delicious, they also have the added effect of protecting the food underneath from drying out. Glazes are glossy thin coatings usually made up of icing sugar, a small amount of water and corn syrup, and sometimes fat (butter or cream). The corn syrup and fat prevent the sugar from producing coarse crystals. In addition, the corn syrup attracts moisture, filling the gaps between sugar particles with a shiny glass-like surface. A simple icing or frosting is made by whipping air into a solid fat such as butter, cream cheese or vegetable shortening, making a creamy, light mass. Using icing sugar will ensure the icing isn't grainy.

If you'd like to learn more about different kinds of icings, check out our guide to Cake Decorating.

Bibliography

• McGee on Food, Harold McGee, Hodder 2004
• Patisserie; A Cooks Book, Loretta Sartori
• Understanding Baking, Joseph Amendola, Nicole Rees 2003, Wiley