18 Role of ingredients used in confectionery industry

Mr. Sanket Borad

Multi-component confectionery products are not new. Their complexity has increased tremendously during the past hundred years or so. Consumer demand for new tastes and textural sensations are the governing factor for the research and development in the confectionery. These are largely attributed by the ingredients used for the preparation of confectionery products.

1. SUGAR

Confectionery has developed around the properties of a single ingredient – Sucrose, a non reducing disaccharide, consists of two reducing monosaccharides namely dextrose and fructose. It has a solubility of 66% at room temperature and 83% under boiling condition. Sugar is prepared either from cane sugar or beet sugar commercially. In general sugars from both sources are identical with slight differences in the impurities profile. Commercially sugars used are available in numbers of forms depending on its particle size. Granulated, milled/icing, coarse, powdered, ultra-fine, caster, non-pareil, fine sugar, etc. can be used as granulated sugar. Sugar syrups can also be used but its stability against microbial spoilage and economy in transportation hinder their uses. Chocolate confectionery employs only standard granulated sugar (sucrose) whereas other forms of sugar find their applications in a wide range of sugar confectionery. Table 1.1 illustrates the use of various forms of sugar for different sugar confectionery.

(Source: Edward, W.P., The science of sugar confectionery)

Other sources of sugar are also used along with cane sugar or beet sugar. These ingredients also carry their own importance in the product formulations and various attributes of finished products as well.

2. INVERT SUGAR

Invert sugar is available as syrup only. It overcomes one of the major drawbacks of sucrose in relation to its solubility as invert solutions can be prepared at concentrations as high as 80% at ambient condition. These solutions have a sufficiently low water activity capable of restricting microbial proliferation. It can be mixed easily with sucrose, can be concentrated sufficiently to yield products that have a sufficiently low water activity without the crystallization of fructose. Invert sugar, when added to a formulation, lowers the water activity and makes the product hygroscopic. Old-fashioned sugar confectionery products are formulated without essential use of invert sugar as they involve heating sucrose in the presence of acid to generate some invert sugar in-situ. The high cost of invert sugar has declined its use with effective replacement with glucose syrup. The later being cheaper and for some uses having superior properties is used. Although the other view is that invert syrup improves the flavour of certain products which is not imparted by glucose syrup. However there is another reason that encourages the use of invert sugar. Sugar-containing wastes can often be treated to produce invert sugar syrup. Recovery of sugar reduces cost of waste treatment, thus had economical considerations which guide the manufacturers.

3. GLUCOSE SYRUP (CORN SYRUP)

Corn syrup, commercial name of glucose syrup, has largely replaced invert sugar as a confectionery ingredient. In fact, some sugar confectionery products contain glucose syrup as a principal ingredient instead of sucrose. Despite the name, maltose is the major constituent of Corn syrup solids (CSS), but not dextrose. Originally, glucose syrup was made from hydrolyzing starch with acid. Nowadays, Glucose syrup can be made from almost any source of carbohydrate. It is economical to produce glucose syrup from maize starch, potato starch or wheat starch. The most common type of glucose syrup in sugar confectionery is 42 DE (or similar). It is even referred to as confectioner’s glucose. Other grades of glucose syrup such as products of 68 DE or equivalent, having the same water activity as invert sugar syrup and so can often be used as a direct replacement. While glucose syrups were made by acid conversion, the DE gave a complete specification of the product. The commercial advantage in terms of cost makes it widely used ingredient because a given weight of glucose syrup solids is cheaper than sucrose. The limited amount of sugar that can be replaced with glucose in a product since 42 DE glucose is less sweet than sucrose and affects the water activity and other properties. The technology of the glucose industry has now developed to the extent that virtually any starch hydrolysate can be produced as per requirement. The application of enzymes to glucose syrups was extended to include the conversion of dextrose to fructose by glucose isomers, resulting syrups were known as ‘high fructose corn syrup’. As the DE of corn syrup increases, the properties like browning, flavour, freezing point depression, humectancy, hygroscopy, osmotic pressure, sugar crystallization, sweetness, etc increases while some properties like cohesiveness, foam stability, viscosity decreases. This gives a brief idea about the corn syrup to be chosen for specific kind of confection.

4. COCOA PRODUCTS

This class of products is solely used in the preparations of chocolate confectionery. The cocoa liquor, cocoa butter and cocoa powder are the principal fractions obtained after processing of cocoa beans. Chocolate powder can also be used where fat is not an important component in the system rather low fat products. The flavour of chocolate depends upon the cocoa solid: sugar ratio in the formulations. It gives the typical flavour which can’t mimic by any other ingredient, it neither requires colour nor flavour addition to the recipe. It offers colour to the product varying from light brown to deep reddish brown colour depending on the pH and the rate of addition.

5. DAIRY INGREDIENTS

Milk cannot be directly employed in the manufacture of confectionery as water that needs to be removed is too great. Milk solids as either milk powder or sweetened condensed milk are favourable choice for confectionery. Chocolate confectionery largely depends on the dried milks only. Skim milk solids form an essential part in formulations of toffees and fudge. Butter or butter oil can be added to compensate for the fat which is likely to be absent in skim milk powder. Skim milk powder (SMP) has the advantage over whole milk powder in that former keeps better, and using skim milk and butter can be economically advantageous under certain conditions.

a. Sweetened Condensed Milk

Sweetened condensed milk (SCM) is the most preferred source of milk solids in toffee manufacture. SCM preparation was one of the earliest ways of producing a stable and long life product from milk. The advantage of skimmed SCM is that the milk fat can be replaced with vegetable fat whenever required. Toffees made from SCM are normally smoother than those made from milk powder; presumably because the milk protein in sweetened condensed milk is in a less damaged form than in milk powder. SCM also has the advantage that provided the tin and it has appreciable shelf life without refrigeration. SCM being sticky syrup needs handling skill; however, it is not an obstacle for confectionery factories.

b. Milk Powder

Milk powder is the other form of milk solids used in confectionery. Spray dried milk powder is used with so many advantages in terms of economy, quality, nutritive properties, reconstitution and functional properties and storage stability as well. In confectionery-making nutritional considerations is not a particular advantage since they do not form a major part of the diet. The less severe heat treatment during milk powder production can create problems since enzymes especially lipase present in the milk are not inactivated, bacterial lipases are much more resistant to heat treatment. Lipase splits fatty acids from glycerol and liberates free fatty acids (FFA) like butyric acid. If the substrate fat is butterfat then at low degree of hydrolysis, it gives a ‘buttery’ or ‘creamy’ flavour. As the FFA content is increased, the ‘cheesy’ flavour becomes pronounced. Normally in toffees free butyric acid is not a problem at any practical level, possibly because of losses during cooking. Other FFAs also contribute to the flavour profile. Lauric acid tastes like soap (sodium laurate is the important component of soap) and so whenever palm kernel oil is used as a butter fat replacer, the risk of development of soapy flavour will arise; another potential source can be nuts, which are sometimes combined with toffee. In either case, lipolytic activity shortens the shelf life of the product or renders it totally unacceptable among consumer.

c. Butter

Butter is used mainly as an ingredient of toffees and butterscotch. The technology of butter preparation does not present any particular problems as any type (sweet cream of lactic) of butter can be used to make toffee. But traditionally, rancid butter is preferred over the rest, if available. Rancid butter is rich in the quantity of free fatty acids. Butyric acid, at low levels, gives a pleasant, buttery flavour. At higher levels, it gives a cheesy flavour and at still higher levels takes on notes of Parmesan cheese. A common approach is to add a little quantity of lipolysed butter to the product which gives the same effect as using stale butter or adding a butter flavour. The lipolysed butter is a butter that has been deliberately treated with a lipolytic enzyme to release the fatty acids. Lipolysed butter can be described as ‘all natural’. Butter is avoided for the use in chocolate confectionery as it gives fat bloom defect.

d. Whey products

Whey, the by-product of cheese-making is a good source of lactose and serum proteins. The only whey product, whey powder, can be used as an ingredient in some toffees, otherwise whey has not been much used in confectionery. The reasons could be unpleasant flavour of whey, high mineral content and high lactose content. Lactose has a very limited solubility (12 time less soluble than sucrose), when used in excess it imparts the unpleasant metallic taste. Intolerance of lactose in certain consumers can not be neglected. However, innovations allow more incorporation of whey in various formulations. But still there is no evidence of major role of this class of products in the confectionery.

6. VEGETABLE FATS

Vegetable fats are the ultimate choice as a substitute for milk fat in the majority of food products including sugar confectionery. Economical factor makes manufactures to switch over vegetable oils as it costs around Rs. 90-150/L as compared to the cost of Ghee which is as high as Rs. 400/L. Apart from cost, feasibility of vegetable fats allows it’s blending, hydrogenation and inter-esterification to produce a vegetable fat with almost any desired range of properties. The most common vegetable fat used in toffees was hardened palm kernel oil which is quite cheap but is a lauric fat that influences the shelf life because of soapy rancidity.

7. HYDROCOLLOIDS: GUMS AND GELLING AGENTS

These ingredients also fall under the class of thickeners and stabilizers. Some make only minor components of confectionery formulations (regarded as additives) while others are used in quantities (regarded as ingredients). The individual agents, their origins and properties are given in Table 1.2.

(Source: Edward, W.P., The science of sugar confectionery)

8. EMULSIFIERS

Emulsifiers are used in a range of confectionery products except in fat-free products such as boiled sweets, gums or jellies. Many times it makes essential to use emulsifies as most chocolate based confections are fat rich. They assist in dispersing the fat and thus alter and stabilize the texture of a product which is a function of the size of any dispersed fat globules. It also facilitates the handling of the product during manufacture by imparting flowability and the ability to be shaped and cut with ease. Use of wrong emulsifier or an excess of emulsifier causes handling problems. There are some materials that are extremely effective emulsifiers but do not qualify as emulsifiers in food law. Milk proteins are one of its classes which have good emulsification properties but do not find their place in emulsifier classification.

Emulsifiers can be eliminated from the recipe of toffees or caramels by using a larger quantity of milk solids but it is rare to find such toffee or caramel. Distilled monoglycerides or a mixture of mono- and diglycerides, lecithin or possibly sucrose esters are used in toffees. Lecithin is almost widely employed whereas sucrose esters are the least. The performance of the monoglycerides depends on the purity of the material; distilled monoglycerides are high purity emulsifiers. Toffee is the class of sugar confectionery which mostly use the emulsifiers. Some other confectionery which has fat-in-sugar type emulsion with whipped air in the structure also contains emulsifier as the essential ingredient.

9. COLOURS

Colour additives are widely used in foods and beverages to mask variations in the natural colour of the product and also compensate the changes that may occur during processing and storage. Colours make products more visually appealing and they emphasize flavours normally associated with various applications. Chocolate confectionery need not any colouring agent in their formulations but dye for the textile industry was used initially for sugar confectionery products. At present the use of colours in foods is strictly regulated and ensured for the safety. Permitted colours are different throughout the world thus some manufacturers produce products without such colorant for the international export markets to make them universally acceptable. Colour has an important influence on flavour perception and so consumer acceptance. An alternative approach is to use coloured wrap for uncoloured products. The wrapper colour can efficiently convey the product characteristics to the consumer. The colouring substances should possess several attributes which make it feasible for ranges of confectionery are:

• It should be stable to heat and light.
• It should be stable to reducing sugar and resistance to sulfur dioxide is also useful.
• It should be water soluble. Most sugar confectionery products contain very little of the fat.

Lake colour is a subclass of colours used for sugar confectionery where opaqueness of the product is desirable such as panned goods, toffee, chewing gum, fondants, chews, bubble gum, etc. They are prepared by precipitating the water soluble colour with aluminium, magnesium or calcium salt onto aluminium hydroxide. Since the solubility is altered, the lake colours do not migrate unlike dye. They can also be used with high fat confectionery products.

10.  FLAVOUR

Chemically, the flavours are complex substances, a combination of both basic aroma and taste compounds. Based on the source, they are classified as: natural, nature-identical and synthetic.

a. Natural flavours

Those which are solely derived from natural sources are labelled as natural flavours. The most common natural flavouring agent is Vanillin which is extracted from plant Vanilla. Some others are based on citrus fruits, herbs, etc. The flavouring agent of the plant is usually extracted by means of solvent depending on the end use. The safety of natural flavours is the main appealing factor for their uses but at the same time there can be some side effect on the health can be debatable issue. The economic factor, stability in the food system, feasibility for use and availability throughout the year and across the world impedes their usages in the industries.

b. Nature-identical flavours

The group of flavouring agents which are present in the nature but can be synthesized to replace the natural counterparts are called nature-identical flavour. Vanillin can be synthesized and used as vanilla flavour. Benzaldehyde can be used as almond flavour. Since they are synthetic, they are tested for safety more exhaustively and proved inherently safer than the natural counterparts. The quite low cost without affecting quality of product makes it more appealing than natural flavourings.

c. Synthetic flavours

Those flavouring agents which are not present in the nature but can be synthesized and used to render the products resembling to nature derived flavours. Typical synthetic flavours are complex group of chemical compounds used where stability in the products under various processing and storage conditions are of prime importance.

11. ANTIOXIDANT

The obvious use of any antioxidant is to check the oxidation of lipid in the food system and thus extend the shelf life by imparting stability to the unsaturated fatty matter against various oxidative mechanisms. BHT (butylated hydrxoanisol) and gallate based antioxidant are widely used in the confectionery recipe. Natural antioxidants like tocopherol can also be used but the effect is not appreciable as compared to synthetic food grade antioxidants.

12. SALT

The common salt is widely used in the food industry for several purposes but the use in the confectionery is guided by only one property – flavour enhancing ability. The salt can be used in the confectionery @ 0.5 % to improve the flavour profile of the product.

13. ACIDULANT

The only intense for the use of Acidulant is to assist the in-situ inversion process during boiling of the content. Citric acid or tartaric acid is used whenever needed in the recipe for the assistance in the inversion of sucrose. Apart from the inversion, it also gives pleasant acid notes.

14. SUGAR SUBSTITUTES

Consumer awareness of the risk at high sugar consumption led to the development of sugar-free food products and that to for almost all foods which has sugar as an essential ingredient. Sugar confectionery is not the exception for that matter. The sugar has to be replaced with two components namely intense bulking agent and sweetener.

1. Bulking sweeteners

This class of sweeteners includes polyols like sorbitol, lactitol, polydextrose, maltitol, isomalt, erythritol, etc.

1. Intense sweeteners

Among the bulk sweeteners, only maltitol or hydrogenated glucose syrup imparts enough sweetness comparable to conventional sugar confectionery. The deficit in sweetness has to be compensated by using an intense sweetener. Some of these substances are not universally legal so the use of intense sweeteners has to be regulated strictly. For example, cyclamates have been banned in certain countries but have remained legal elsewhere, and stevioside is legal in Japan but nowhere else.

Whenever intense sweeteners are used, claims are made of synergy between sweeteners, i.e. a blend of sweeteners provides more sweetness than the sum of the amount provided by each singly. There is evidence of this effect in soft drinks although in confectionery evidence is less apparent. Synergy is not just a crude numerical effect. There can be synergy between rapid onset sweetness as in aspartame combining with another sweetener with slow onset sweetness.

Suggested readings

• Chocolate, Cocoa and Confectionery: Science and Technology (3rd Ed.) by Bernard W. Minifie

• The Science of Sugar Confectionery by W. P. Edwards

• Modern Technology Of Confectionery Industries With Formulae & Processes by Minni Jha