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Home , Caramel, Toffee

Paper No. 09 Paper Title: Bakery and Technology Module No. 28 Module Title: Technology of , and

1. CARAMEL 1.1 History

Initially of fruits and nuts dipped in were prepared by Arabs and Chinese. But during the Middle Ages, refined of any kind was very expensive and a rare treats. By the early 19th century, Americans used juice to make new candies and so were invented in USA in 19th century.

Originally, the production of caramels occurred using copper pots over direct gas flames, watched carefully by a master confectioner who used a thermometer to monitor the temperature, and poured out the cooling caramel batch onto a marble slab or a water-cooled table and scored it into squares.

1.2 Background

Caramels may be described as “soft glasses” that are viscous in nature and contain a dispersion of milk protein and an emulsion of fat (Jeffrey, 2001). Caramel is a popular and widely consumed confection that produces images of delicious, chewy treats in the minds of consumers. Caramel may be found in a range of textures, colours, flavours and products, may be consumed alone as or in combination with , , marshmallows, nuts, and other inclusions. The properties of individual caramels are dictated by ingredient formulation and processing. The best caramels are sweet and just a bit chewy. Caramel manufacturers use the term "short" to characterize a caramel that is too soft (perhaps too moist) or "long" for a caramel that is quite chewy. Caramels are softer because they have been cooked to a lower temperature than hard candies (to approximately 118°C, or the firm ball stage) and contain more moisture.

Because of this soft texture, caramel may be extruded at lower temperatures which can be moulded, and put into a variety of other candies or candy bars to add flavour, binding, and texture. The action of the heat on the milk solids, in conjunction with the sugar ingredients, imparts a typical caramel flavour to these sweets. Essentially, the entire batch of candy

undergoes the Maillard browning reaction. In a conventional process, the sugar are cooked to the proper moisture level, added to the fat and milk, heated, and then allowed to caramelize (develop the characteristic flavour and brown colour) in a browning kettle.

1.3 Raw materials

Different raw materials are used depending on the manufacturing and type of caramel under production. However, the most frequently made caramel, the vanilla caramel, contains many ingredients if it is mass-produced. The ingredients include milk, sometimes sweetened , corn , sugar, oil, whey, calcium carbonate, salt, flavour, and , another type of fat such as vegetable oil, , and corn starch. Milk is essential to distinguish the caramel from a , and it is the milk solids that change chemically to produce the caramel.

Corn syrup lends additional to the candy batch but also protects the mixture from becoming grainy, which would indicate there is too much sugar in the batch (graininess will ruin a batch of caramels). also lends body to the slurry. At least one fat is added to the mixture as well. Butter is often the only fat added by gourmet caramel-makers as it provides superior taste, but this proves to be very expensive for mass-production. So other fats are added along with a fairly small amount of butter. As maple caramels or other flavoured caramels are produced, the ingredients vary accordingly.

1.4 Manufacturing process

There are various stages of sugar solutions which are described by solutions behaviour when dropped in cold water. Below given are the stages which are involved in the caramel production.

Stages Temperature (°C) Characteristics

Thread stage 110-112 Solution thicken into syrup threads when you pull a spoon out

Short ball stage 112-115 Solution can be pressed to soft gooey ball. Used to make soft chewy candy like

Firm ball stage 117-121 Solution can be pressed into a firm ball. Used to make caramel

Below given process is one of the processes used for manufacturing of caramel; however there are many different processes used in industry for the manufacturing of caramel. The process is essentially the same, as batch process-the batch is machine mixed, cooked steadily, cooled, extruded, and formed into small squares.

1. All of the ingredients listed above are automatically batched and weighed using a batching and dissolving machine made expressly for the manufacture of caramels. The liquid and the dry ingredients are loaded into the machine. Then, the ingredients are weighed with great precision by computer in the weigh tank (which may be on the upper side). The ingredients are mixed by propellers in this weigh tank.

2. After blending, this milky slurry drops automatically to the lower mixing and dissolving tank. Steam heat brings the mixture up to a pre-determined temperature. In the mix tank, gear- driven agitation equipment dissolves the ingredients thoroughly. Surface scrapers skim along the bottom and sides where burned protein solids have a tendency to accumulate. These burned solids are redistributed and mixed back into the slurry to ensure that the whole mixture is a homogeneous batch.

3. The heated mixture is then sent to the heated surge tank. An operator's command transfers the batch into a stainless steel scraped surface heat exchanger for the final evaporation. Here a small variable-speed gear motor drives a scraping system within the evaporator. The syrup is forced through a small space that is jacketed with steam, thus forcing evaporation within the mixture.

4. The batch has now had much of its moisture removed and is thickening. It is gravity-fed into a steam-jacketed caramelizing tank where the caramelizing is ensured by exposing the batch to steam. The caramelizing mixture is re-circulated from the bottom to the top of the tank, with incoming syrup mixing with the caramelizing slurry, promoting homogeneity of the product. A discharge valve directs the mixture into the next processing machine, the cooling wheel.

5. This caramel candy, now at about 116°C, has to be cooled. There are many ways to cool the caramel; including moving it into cool rooms and running it through cooling tunnels. The

system described above utilizes as cooling wheel. The caramel is water-cooled on the outside surface of a large wheel that is 4ft wide and 12ft in diameter. The caramel is laid in a film about 1/8-inch (3.2-mm) thick on this wheel. The wheel completes a half turn and the caramel comes off the wheel, becoming solid and of a consistency so that the candy may be cut and packaged.

6. A batch roller takes the caramel film and shapes it into a rope. The rope is then shaped and sized into the thickness of a finished caramel. Caramels are not moulded; instead, they are shaped by being cut from the thick rope. As the caramels are cut they are automatically individually wrapped. From there, the caramels may be weighed and placed in a sealed bag and packed into cartons for shipping. If caramels are cooked to just the correct temperature, they can be shipped easily in any type of weather and will hold their shape. If they are undercooked just by a few degrees, they may do poorly after packaging and become too soft.

1.5 Quality control

The machinery involved in the process of is automated. The making of caramels requires precise measurements of ingredients, since too much sugar makes the candy grainy and makes it an inferior product. If there is too much moisture in the product, the caramel will be too gooey in warm weather. Too little moisture and cooked at too high a heat, and a "long" or chewy caramel is the result. So, the machinery must be very carefully checked and calibrated for accuracy in the mixing and weighing of materials. Insufficient mixing while may lead to either of two predominant tastes - a 'grittiness' due to the proteins not being evenly dispersed or an 'oily' taste if the fat was not fully emulsified.

The type of cooker used may greatly affect the product made relative to shear rate, cooling time and mixing efficiency. Temperature controls, too, must be extraordinarily accurate, since just a few degrees can affect the consistency of caramels. Human operators on the floor use their eyes and hands in order to maintain quality. Master caramel-makers are essential to the production of gourmet caramels, made in smaller batches at a time. Their experience can detect any slight variation that may result in an inferior batch just by the look, smell, and feel of the batch.

As with all food manufacture, the quality of all consumable ingredients must be checked for quality. Corn syrup must be of the high quality needed for this candy manufacture. All other

ingredients must be tested for quality as represented by the suppliers. It will be obvious that judgment and consistency of product quality depended totally on the skill of the confectioner.

2. TOFFEE 2.1 Introduction

Toffees are high-boiled products containing , sugar or invert sugar and fats, usually butter. These products have moisture level less than 5%. Most are chewable rather than glassy. Toffees have lower moisture content than caramel and having harder texture. As toffees normally have dispersed fat in them, they are emulsions. Toffees are nearest the oil-in-water category of emulsions since water itself is only a minor constituent of a finished toffee; the continuous phase of a toffee is a sugar and mix. In these products the crystalline or grainy texture developed during processing and structure is stabilized before product is packed.

2.2 History

The origin of the word „toffee‟ seems to be lost in time although it might be derived from „taffy‟, a dialect word for „sticky‟. The development of Mackintosh‟s toffee is regarded as important as it was said to combine the attributes of soft American caramel with English hard toffee. The resulting chewy product had the advantage that it could be sold all around the world without refrigeration. Because of this history, in the UK at least, toffee and caramel seem to be used interchangeably, and toffee is used to refer to products ranging from viscous liquids to hard sugar glasses.

2.3 Ingredients

The basic ingredients used in the production of toffee are:

i. Sugar () ii. Glucose syrup iii. Milk Protein iv. Fat v. Salt vi. Water vii. Other additives e.g. colour, flavour etc.

2.4 Structure of toffee

Toffee is an emulsion of fat in complex aqueous system. It is a mixture of , water and protein which is resistant to crystallization. Toffees have number of textural characteristics:

 Hardness is a function of moisture content.  Chewiness and toughness on eating are related to molecular weight of the carbohydrates  Body is a function of quantity and state of the milk protein and it is affected by quantity ,degree of emulsification and hardness of fat

All these characteristics of different ingredients affecting the eating characteristics of the toffee and by varying ratio of the ingredients and alternative ingredients use leads to give the desired texture of the toffee.

2.5 Formulation

It depends on the requirements of the toffee, which may be for wrapping as a sweet, for depositing into chocolate shells or layering on to other confectionary products. In general balanced recipe contains 3 parts of sugar, 5 parts of glucose syrup, 3 parts of sweetened condensed milk and 1 part of fat. For wrapped toffees, the ration of sugar to non-crystallizing sugars should be 1.1:1. For deposit product milk protein used up to 2 % acceptable above this may create problems. For deposit into shells low viscosities at low temperature are required and thinning with syrups of low molecular weight sugars may be necessary.

2.6 Processing

Toffees can be made using equipment ranging from an ordinary saucepan to a large continuous plant. The processes carried out are fundamentally similar.

a. Dissolving

Solid sugars are first dissolved in water or a mixture of water and glucose syrup.

b. Emulsifying

The fat and skim milk solids are added into the dissolved sugar or glucose syrup which makes the emulsion.

c. Cooking

The emulsion is then cooked to achieve the final water content. It is controlled by measuring the boiling point of 118-132°C for regular toffee and 146-154°C for hard toffee. If the cooking is done in a saucepan or steam pan, the toffee can then be passed to the next stage. If the toffee has been cooked in a high technology cooker such as a wiped film or a scraped surface heat exchanger the moisture is evaporated so rapidly that caramelization has no time to occur. In such systems either a pressurized pre-heater or a steam-heated post-cooking holding vessel must be provided. The residence time in these vessels is then adjusted to give the desired colour and flavour, and various continuous cookers have been produced with the specific aim of matching the pan boiled product. It is possible to have a system where the pre-boil emulsion is made on a batch basis but which is cooked on a continuous basis once made.

Converting a long-established product from a batch to a continuous process can create a lot of problems. The product made on the continuous plant often has a different texture and taste to the original product, other relate to rheological changes that occur during the cooking process.

d. Shaping the Toffee

The finished toffee has to be shaped in some way. Toffee is normally run into trays, cut into slabs or used as a component of other confectionery. There are three processes used for shaping toffees for individual twist wrapping. The processes are the slab process, cut and wrap processing as well as depositing.

i. Slab Process

This is a very old-fashioned way of shaping toffee. The toffee is poured, usually manually, onto water-cooled slabs. In order to facilitate manipulation of the toffee the slabs are coated with a release agent. Traditionally, this was a mineral oil although its use has been banned and long-life vegetable fats are now used. Because toffee is a poor conductor of heat it must be turned over on the slab to bring the cooler outer part into the middle and to bring the hotter middle onto the slab. If the toffee was just left on the slab to cool without turning the outside would be hard before the middle had cooled down. After sufficient cooling the toffee is cut into sheets before being cut into individual pieces.

ii. Cut and Wrap Process

In this process the toffee is cooled, usually by pouring it onto a cooled metal drum or band although cooling could be carried out on a slab if required. The temperature of cooling must not go low enough to cause condensation, which will occur if the product is below the dew point. The cooled product is then fed to rollers known as batch rollers that shape the mass into a cone and then a rope. The rope then passes through further rollers to reduce the thickness of the rope and then past forming wheels that produce the desired cross section. The product is cut with a rotating knife and the pieces are fed onto the wrapping paper and twist wrapped. Modern machines work at very high speeds. Although it is very quick, one problem with this type of system is that the individual pieces of toffee are distorted during wrapping.

iii. Depositing

This is the most modern process of the three. Soft caramels can be deposited into starch moulds or chocolate shells which are later sealed by adding a chocolate back. The high technology method is to deposit the toffee into rubber moulds. The problem of making such a deposit is that the depositing machinery must be kept sufficiently hot for the toffee to flow without any further loss of water. Toffee can thicken up if held for too long at high temperature. In the subsequent cooling stage the problem is to abstract heat from the product and to do it without cooling it so much that condensation occurs. The rate at which heat can be removed

from the finished toffee is controlled by the thermal conductivity of the toffee, which is low. After cooling, the toffees are fed to the wrapping machine for packing.

2.7 Toffee texture

Toffee textures are sometimes modified by the incorporation of air, which is introduced by mixing in a whipped frappe, and toffees are frequently combined with other confectionary products. In these conditions the main attention on the relative humidity of the separate components as, it may lead to moisture transfer to the sweets leading to change in the texture and in case of dried nuts and fruits which lead to prevent moisture being introduced into the toffee and initiating grain.

Reworking toffee products depends on the type of process involved. Solid rework can be added back either on the slab or into the boiled batch but, care should be taken that no grain developed on the surface of the rework. It is safer to dissolve the rework to premix solid and feed it back at the premix stage. It has been said that a proportion of rework improves toffee texture and improves flow characteristics in depositing processes.

2.8 Packaging and storage

Toffees are mostly packed in individual wraps can be made from waxed paper, aluminium foil and cellulose film or a combination of these. In most cases toffees 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.

Toffees are mostly stored under the ambient conditions of temperature and humidity.

3. FUDGE 3.1 Introduction

Fudge, a grained product, is a „fondant‟ containing milk protein and fat, often butter fat, and having characteristic flavour of caramel or toffee. Fudge can also be defined as a hybrid confection, a cross between caramel and cream. Perhaps the first fudge was made by someone accidently graining a batch of caramel. Fudge have wide range of texture from the hard „snappy‟ texture of traditional Scottish cut „‟ with its very high sugar content, to the soft tender

texture of chocolate coated starch moulded units. Often an egg whip is added to give a light „fluffy‟ texture similar to a soft crème.

3.2 Ingredients

The main ingredient used in the production of is Sugar (Sucrose). The basic ingredients of fudge are as below:

 Sugar  Glucose syrup  Milk protein  Fat  Salt  Water 3.3 Composition Components Proportion

Reducing sugar solids 17-25% Sugar 45-55% Fat and Milk solids 20% Moisture 7-10% (Jackson, 1990)

3.4 Processing

The basic unit operations in fudge manufacture are:

 Pre-Mixing  Emulsification  Cooking/Caramelizing  Cooling  Graining  Forming

i. Pre-Mixing

All the ingredients such as sugar, glucose syrup, milk solids, fat, water (if required) and salt are blended. Ideally the fats, milk and glucose should be emulsified before the sugar is added. The reason for this is to disperse the fat into aqueous syrup to prevent it coating the sugar and retarding solution.

ii. Emulsification

The emulsification is usually achieved in a high shear mixing stage between pre-mixing and cooking for typically 10-20 minutes while maintaining a temperature of 70-80°C. The emulsification of the ingredients is carried out with the stirrers on high speed. Ultrasonic homogenizers can also be used. Adequate emulsification is essential to optimize the flavour and to prevent fat separation during processing or storage. iii. Cooking/ Caramelization

The emulsified batch is cooked with constant scrapping to final temperature (116°C) required to give the final moisture content. During cooking the batch will caramelize and develop characteristic flavour and colour. Caramelization is time and temperature dependent and a typical cooking time is 20 minutes. Flavours are usually added at the end of cooking. Under batch processing conditions the degree of caramelization is affected by the quantity of protein, the quantity and type of and time taken to reach the final boiling temperature.

There have been several different methods developed to cook and caramelize continuously; some examples are:

 Thin-film or scraped-surface cooker in which the heat transfer rates are high, and evaporation occurs so rapidly that caramelization has no time to develop.  Plate heat exchanger for compactness and absence of moving parts. Capacity can be varied while dissolving and cooking sections can be part of same plate assembly. iv. Cooling

At the end of the cooking, butter may be added if required and either excess fondant added to bring the temperature below 105°C. The batch can be cooled by passing water through the pan jacket.

v. Graining

The grained structure of fudge can be produced by induced sugar crystallization. Use of fondant to provide seed crystal is almost universal. However, fondant crystal is destroyed in a hot batch, so cooling off the boil to about 105°C is required to ensure adequate crystal present when the batch is poured. The most common method is by pouring onto a slab, cooling, and traying off until crystallization has stabilized and then cutting, but fudge can be deposited into trays or moulds. Alternatively beating can be employed to control the process of crystallization and produce crystals of a same size. The fudge mass is poured onto the table, left to cool, and then beaten with a wood or metal beater. vi. Forming

Forming of finished products can be carried out by means of any of extruding, bar forming, depositing (starch or starchless), filling into plastic or foil trays, cut and wrap, stamping into shapes, etc.

3.5 Packaging and Storage

A moisture proof individual wrap of waxed paper, aluminium foil and cellulose film or a combination of these can be used for packaging of fudge. Semi-automatic wrapping machines are also available for higher productions. For further protection, the individually wrapped sweets may be packed in a heat-sealed polythene bag and then stored at room temperature or refrigerated conditions.