Introduction
When it comes to consumption of Confectionery products by children and adults, there is a general tendency to prefer chocolates as compared to cakes, cookies, wafers and crackers. Since confectionery products are low in nutritional components, they may cause diet and energy imbalances. The high calorie confectionery food products are mostly prepared with fat.
An emulsion generally involves the scattering fat globules that are mixed into a liquid medium. Thermodynamically, an emulsion in confectionery products is unstable, but can be stabilized using emulsifiers. Emulsifiers are divided into natural ones – LECITHIN and synthetic emulsifiers – MONO/DIGLYCERIDES and their derivatives. The two major functions of an emulsifier are the combination of two different phases of the product (like oil in water, water in oil) and the modification of the nature of the products for ages. Emulsifiers are amphiphilic, i.e., they act as hydrophilic and lipophilic, denoted as HLB and indicated on a scale from 0 to 20. A lower number is likely to be oil in nature and a higher number will be water in nature. For example: for lecithin, HLB will be around 4 and act more like oil in nature for chocolate.
Lecithin
Lecithin is a phospholipid and a natural emulsifier that provides both lipophilic and hydrophilic properties. The E-number for lecithin is E-322 and the dosage level of lecithin is less than or equal to 1%. Lecithin is obtained from both plants and animals, but lecithin from the animal source gives more yield than plants, from egg yolk – 8 to 10%, whereas soybean oil – 2 to 2.5%. Commercially lecithin is taken from soybean and is an important byproduct of soybean oil. The molecular formula for lecithin is C35H66NO7P.
Manufacturing Of Lecithin
Lecithin is manufactured by degumming crude oil, drying, cooling and standardizing crude lecithin.
- DEGUMMING: This can be done by 4 methods – water, acid, enzymatic and membrane filtration. However, water degumming is best for obtaining high-quality lecithin. Water is added to the oil and separated through a centrifugal separator.
- BLEACHING: Benzoyl/hydrogen peroxide is used to remove the colour.
- COOLING/DRYING: This should be done in a batch dryer for 3-4 hours. Storing lecithin at low temperatures can extend its shelf life.
Applications of Lecithin
Lecithin is used mainly in chocolate and sugar confectionery as emulsifying agents and surfactants respectively. Since, lecithin is a non-chemical food additive, it is used in the market as an ingredient for various products. The incorporation level of lecithin will be around 0.1% to 2% in food products, a healthy and dietary ingredient. Lecithin has both a water-loving and water-hating compound for making oil and water emulsion. The water-loving compound gets mixed with fatty substances, so that the surface will show oil in nature.
1. Chocolate Confectionery
Chocolate is the most popular confectionery product consumed by a human from birth to death. The main reason for consuming lots of chocolate is that it gives instant energy and boosts the mood in people. Emulsifier like lecithin is used in chocolate making for proper mixing of sugar and butter, reducing the internal particle interaction and getting a better consistency. Lecithin increases the moisture barrier properties and reduces the viscosity.
About 0.5% of lecithin can reduce the viscosity of chocolate from 300 Pa/s to 100 Pa/s. Adding a small amount of lecithin after conching increases the liquefication property of chocolate, because the emulsifier has a greater flow behaviour effect in chocolate. Lecithin can also prevent or decrease the time of blooming effect on the surface of the chocolate. The formation of a white colour spot known as BLOOM occurs when chocolates are not stored properly. These blooms can also be prevented by adding other emulsifiers like Sorbitan Tristearate (STS), Sorbitan monostearate (SMS) and Polysorbate.
2. Sugar Confectionery
In chocolate confectionery, we used lecithin for oil, butter or fat emulsification, but emulsifiers are used for nutritious carbohydrate sweeteners like sugar and sugar syrup. Modification of flavour and texture of the product had occurred, due to the emulsifier effect on sugar, lipophilic substances and a small amount of other fat-soluble compounds. Dispersion of fat with other ingredients forms chewing characteristics and improves the texture. 1% lecithin is used to manufacture the chewing gum to get softening consistency and give a protective coating. About 0.25% to 0.7% of the usage of lecithin and other emulsifiers in toffee, caramels and butterscotch is effective and normal. Lecithin is added to jellies and gums according to ACI ( Amylose – Complexing Index), i.e., the formation of permanent texture, which is water insoluble complex when amylase and emulsifier get mixed. The ACI value for gum and jellies is 16.
Interaction between Food Components and Lecithin
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Protein And Lecithin
Normally, ionic emulsifiers react more rapidly with proteins than non-ionic ones. The effect of polar lipids with protein depends on the phase structure of the product and lecithin at the activity time. Interaction between the protein and lecithin shows mutual or interdependent effects, i.e., either protein or lecithin gets over from the interface. The reaction between the protein and the lecithin can be judged by some practical experiments like Emulsion Capacity Test: the maximum amount of oil mixed with 1 gram of protein; Emulsion Activity Test: forming of emulsion when a small amount of oil is added to water-protein dispersion and Emulsion Stability Test: formation of heatstable emulsion by the protein that remains unaffected when kept at a particular time. The interaction between them may give rise to the following:
- Enhanced emulsion stability of oil in water emulsion;
- Formation of lecithin protein complexes;
- Reduction of the surface activity;
- Distribution of net charges of the surface;
- Unfolding of protein.
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Carbohydrates and Lecithin
Carbohydrates are a vast component of food. These are mono-, di-, oligo- and non-starch polysaccharides, which are less reactive with an emulsifier. In contrast, starch polysaccharides react with an emulsifier, form a complex and change the characteristics of starch. Formation of clathrate or inclusion complex due to the interaction between the linear molecules like amylose and fatty acid chain (fatty adjunct), i.e., the lipophilic part of emulsifier forms a helical structure called complex. Gelatinization or gelation can be altered and controlled by using a starch-emulsifier complex. These interactions between the emulsifier and starch hold back the formation of the crystalline site partially, which affects the texture and this phenomenon is known as Retrogradation.
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Fat and Lecithin
Adding lecithin to fat causes the destabilization of oil in water emulsion, flocculation and coalescence. They also decrease surface tension. About 0.5% of fat content is homogenized and spread by adding lecithin, due to unsaturated fatty acid. They increase the viscosity and complexity nature of fat. The addition of lecithin can lower the hardness and work of shearing. Its addition alters only a small number of thermal degrees.
Future Trends in Emulsifiers
Emulsifier used in raw or processed food product increases the shelf life, holding the physical, chemical and microbiological properties for shipping long distances and decreasing spoilage without refrigeration. According to the recommended value of dietary fat, not exceeding 30% of calories, replacing solid fat with liquid oil in most manufacturing companies increases the usage of emulsifiers. Some of the microbes are termed food-grade organisms that are used to produce natural and efficient surfactants. Emulsifier interacts with food components like protein, fat and carbohydrates and forms complex structures exhibiting improved and advanced product functionality. Hence, it is also termed as a functional food ingredient.
Conclusion
The Confectionery Industry is unique and special in India. Confectioneries are categorized into chocolates, chewing gums, jellies, candies and toffees. There is a huge demand by the consumer for food products with high quality, convenient as well as safe food with an extended shelf life. While about 70% of the population consume confectionery products in urban areas, around 30% consume the same in the rural areas. Further, there are many more healthy confectionery products available around the world. The manufacturer needs to find the healthy formulations to satisfy the consumer demands.
References:
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