Nutritional significance
Principles of sugar confectionery production
Processing
Packaging
Suitability for small-scale production
Sugar confectionery refers to a large range of food items, commonly known as sweets. Boiled sweets, toffees, marshmallows, and fondant are all examples.
Sweets are a non-essential commodity, but are consumed by people from most income groups. The variety of products is enormous, ranging from cheap, individually-wrapped sweets, to those presented in boxes with sophisticated packaging.
The main ingredient used in the production of sweets is sugar (sucrose). There is a danger that if sweets are consumed in excess over a prolonged period of time they may contribute to obesity. Unless good dental care is practiced, over-consumption can also lead to tooth decay.
By varying the ingredients used, the temperature of boiling, and the method of shaping, it is possible to make a wide variety of products. In all cases, however, the principle of production remains the same and is outlined below:
· balance the recipe
· prepare the ingredients
· mix together the ingredients
· boil the mixture until the desired temperature has been reached
· cool
· shape
· pack.
Many factors affect the production and storage of sweets:
· the degree of sucrose inversion (see below)
· the time and temperature of boiling
· the residual moisture content in the confectionery
· the addition of other ingredients.
Degree of inversion
Sweets containing high concentrations of sugar (sucrose) may crystallize either during manufacture or on storage (commonly referred to as graining). Although this may be desirable for certain products (such as fondant and fudge), in most other cases it is seen as a quality defect.
When a sugar solution is heated, a certain percentage of sucrose breaks down to form 'invert sugar'. This invert sugar inhibits sucrose crystallization and increases the overall concentration of sugars in the mixture. This natural process of inversion, however, makes it difficult to accurately assess the degree of invert sugar that will be produced.
As a way of controlling the amount of inversion, certain ingredients, such as cream of tartar or citric acid, may be used. Such ingredients accelerate the breakdown of sucrose into invert sugar, and thereby increase the overall percentage of invert sugar in the solution. A more accurate method of ensuring the correct balance of invert sugar is to add glucose syrup, as this will directly increase the proportion of invert sugar in the mixture.
The amount of invert sugar in the sweet must be controlled, as too much may make the sweet prone to take up water from the air and become sticky. Too little will be insufficient to prevent crystallization of the sucrose. About 10-15 per cent of invert sugar is the amount required to give a non-crystalline product.
Time and temperature of boiling
The temperature of boiling is very important, as it directly affects the final sugar concentration and moisture content of the sweet. For a fixed concentration of sugar, a mixture will boil at the same temperature at the same altitude above sea-level, and therefore each type of sweet has a different heating temperature (see chart below).
Boiling point of sucrose solutions
|
Sucrose concentration (per cent) |
Degrees C Boiling point * |
Degrees F Boiling point * |
|
40 |
101.4 |
214.5 |
|
50 |
102 |
215.5 |
|
60 |
103 |
217.5 |
|
70 |
105.5 |
222 |
|
75 |
108 |
227 |
|
80 |
111 |
232 |
|
85 |
116 |
241 |
|
90 |
122 |
252 |
|
95 |
130 |
266 |
*at sea level.
Variations in boiling temperature can make a difference between a sticky, cloudy sweet or a dry, clear sweet. An accurate way of measuring the temperature is to use a sugar thermometer. Other tests can be used to assess the temperature (for example, toffee temperatures can be estimated by removing a sample, cooling it in water, and examining it when cold). The temperatures are known by distinctive names such as 'soft ball', 'hard ball' etc., all of which refer to the consistency of the cold toffee.
|
Type of sweet |
Temperature range for boiling (Degrees C) |
|
Fondants |
116-121 |
|
Fudge |
116 |
|
Caramels and regular toffee |
118-132 |
|
Hard toffee (e.g. butterscotch) |
146-154 |
|
Hard-boiled sweets |
149-166 |
Moisture content
The water left in the sweet will influence its storage behaviour and determine whether the product will dry out, or pick up, moisture.
For sweets which contain more than 4 per cent moisture, it is likely that sucrose will crystallize on storage. The surface of the sweet will absorb water, the sucrose solution will subsequently weaken, and crystallization will occur at the surface - later spreading throughout the sweet.
Added ingredients
The addition of certain ingredients can affect the temperature of boiling. For example, if liquid milk is used in the production of toffees, the moisture content of the mixture immediately increases, and will therefore require a longer boiling time in order to reach the desired moisture content.
Added ingredients also have an effect on the shelf-life of the sweet. Toffees, caramels, and fudges, which contain milk-solids and fat, have a higher viscosity, which controls crystallization. On the other hand, the use of fats may make the sweet prone to rancidity, and consequently the shelf-life will be shortened.
Types of sweets
Fondants and creams
Fondant is made by boiling a sugar solution with the optional addition of glucose syrup. The mixture is boiled to a temperature in the range of 116-121°C, cooled, and then beaten in order to control the crystallization process and reduce the size of the crystals.
Creams are fondants which have been diluted with a weak sugar solution or water. These products are not very stable due to their high water content, and therefore have a shorter shelf-life than many other sugar confectionery products. Both fondants and creams are commonly used as soft centres for chocolates and other sweets.
Gelatin sweets
These sweets include gums, jellies, pastilles, and marshmallows. They are distinct from other sweets as they have a rather spongy texture which is set by gelatin.
Toffee and caramels
These are made from sugar solutions with the addition of ingredients such as milk-solids and fats. Toffees have a lower moisture content than caramels and consequently have a harder texture. As the product does not need to be clear, it is possible to use unrefined sugar such as jaggery or gur, instead of white granular sugar.
Hard-boiled sweets
These are made from a concentrated solution of sugar which has been heated and then cooled to form a solid mass containing less than 2 per cent moisture. Within this group of products there is a wide scope to create many different colours, flavours and shapes through the use of added flavourings and colourings.
The table below outlines the processing stages for a selected range of confectionery items.
|
|
Mix ingredients |
Boil |
Cool |
Beat |
Form/set |
|
Hard-boiled sweets |
* |
* |
* |
|
* |
|
Fondant |
* |
* |
* |
* |
* |
|
Toffees/caramels |
* |
* |
* |
|
* |
|
Fudge |
* |
* |
* |
* |
* |
|
Jellies |
* |
* |
* |
|
* |
|
Marshmallows |
* |
* |
* |
* |
* |
Boiling
There are three main ways by which to boil the sugar solution:
· a simple open boiling pan
· a steam jacketed pan
· a vacuum cooker.
Steam jacketed pans are often fitted with scrapers and blades which make the mixing and heating process more uniform, and lessen the possibility of localized over-heating. Vacuum cookers are not generally used at a small scale.
Cooling
All sweets are cooled slightly before being shaped. Most simply, the boiled mass is poured onto a table (this should be made from metal, stone, or marble to cool the product uniformly). The table should be clean and free from cracks, as they may harbour dirt and microorganisms.
It is important that the boiled mass is cooled sufficiently, since if it is to be formed by hand there is a danger that the operator may suffer burns.
Equipment required
|
Processing stage |
Equipment |
Section reference |
|
Mix ingredients |
Weighing and measuring equipment |
64.1 and 64.2 |
|
Boil
|
Heat source |
36.0 |
|
Boiling pans |
48.0 |
|
|
Steam jacketed pans |
48.0 |
|
|
Thermometer |
63.0 |
|
|
Cool |
Table |
|
|
Beat |
Hand whisk or liquid mixer |
43.1 |
|
Form/set |
Starch mould cutting equipment |
17.1 |
|
Pack |
Waxed papers cellulose films aluminium foils or polythene bags |
|
|
Heat sealer |
47.1 |
|
|
Wrapping equipment |
47.3 |
Beating
Beating is a process which controls the process of crystallization and produces crystals of a small size. For example in the production of fudge, the mass is poured onto the table, left to cool, and then beaten with a wood or metal beater.
Forming/setting
There are two main ways of forming sweets: cutting into pieces, or setting in moulds.
Moulds may be as simple as a greased and lined tray. Other moulds can be made from rubber, plastic, metal, starch, or wood. It is possible to make starch moulds by preparing a tray of cornstarch (cornflour), not packed too tightly. Impressions are then made in the starch using wooden shapes. The mixture is poured into the impressions and allowed to set.
When sweets are stored without proper packaging, especially in areas of high humidity, the sucrose may crystallize, making the sweet sticky and grainy. Traditional packaging materials such as banana or sugar-cane leaves are often used to wrap sweets. However, these do not provide sufficient protection for a long shelf-life because they are not efficient barriers to moisture and cannot be securely sealed.
Alternatively, individual wraps can be made from waxed paper, aluminium foil, and cellulose film, or a combination of these. In most cases, the sweets will be wrapped by hand, but for higher production, semi-automatic wrapping machines are available. For further protection, the individually-wrapped sweets may be packed in a heat-sealed polythene bag.
Sweets can also be packaged in glass jars, or tins with close fitting lids.
Certain types of sweets such as hard-boiled sweets require good quality ingredients (such as white granulated sugar). Such ingredients often need to be imported from other parts of the country, as they may not be widely or cheaply available in all areas.
It is possible to produce high-quality sweets on a small scale using inexpensive pieces of equipment. However, an open boiling pan gives less control over the boiling process and ultimately less control over the quality of the finished product. If simple equipment is used, the process will rely heavily upon the producer's experience and skills in production.
By using the basic principles of sweetmaking, the producer can use her/his creative skills to produce a wide range of products from local resources and materials.
