Fresh cocoa beans contain a lot of water and have no aroma. After baking and fermentation, they have a strong fragrance, which is formed by a variety of amino acids decomposed by fermentation. In addition, cream, milk powder, malt, almond, vanillin and other aroma components are added in the processing process, which makes chocolate have a special aroma.
Chocolate candy contains high fat, high protein, high sugar and high calorie. The melting point of cocoa butter is close to human body temperature. Cocoa beans are also rich in vitamins and trace amounts of theobromine. The particles of caffeine and other nerve stimulating substances are highly emulsified, forming good color, fragrance and taste, which makes chocolate candy have high nutritional value and easy to digest and absorb.
There are many kinds of chocolate candy, which can be divided into pure chocolate, nut chocolate, sandwich chocolate, wine chocolate and nut paste chocolate. In recent years, there is a trend of snack chocolate abroad.
Chocolate candy consists of cocoa products, sugar and dairy products. Cocoa products are products made from cocoa beans, including cocoa liquor, cocoa butter, cocoa candy and so on.
1. Cocoa liquid mass: also known as cocoa or bitter substances. Cocoa beans are baked, shelled, ground into paste, and cooled to form a brown block solid with aroma and bitterness, which belongs to semi-finished raw materials. The moisture content of cocoa liquor should be less than 4%, and the fat content should be less than 55%. Those less than 45% do not meet the requirements.
2. Cocoa butter: It is fat extracted from cocoa liquor, which is milky yellow. Liquid cocoa butter is hard and brittle at room temperature, and it is solid after cooling and shrinking. Cocoa butter has a beautiful and unique fragrance. Cocoa butter consists of various triglycerides.
3. Cocoa powder: Cocoa powder is a cake after extracting cocoa butter from cocoa liquid. The processing methods of cocoa powder are divided into ordinary preparation method and alkali treatment method.
Different varieties of chocolate have different ingredients, as shown in the following table:
fundamental/essential component
Milk chocolate (common)
Milk chocolate (high-grade)
Milk chocolate (for clothes coating)
Cocoa liquid block%
10~ 12
1 1~ 13
10~ 12
Cocoa butter%
22~28
22~30
22~30
Sugar%
43~55
40~45
44~48
Milk solids%
10~ 12
15~20
13~ 15
Total oil percentage
30~38
32~40
35~40
The principle of making chocolate candy has the characteristics of lubrication, delicacy and attractive aroma, which is determined by its raw materials and manufacturing technology.
In the production process, all solid substances in chocolate products are dispersed into tiny particles, so that all soluble substances and insoluble substances become tiny particles, making chocolate very delicate and smooth.
Secondly, the mixing degree of various raw materials of chocolate products is the highest. After the mixing is highly uniform, there are phenomena such as sugar not coming out and oil not coming out. , so as not to affect the appearance and organizational structure of chocolate products.
Therefore, it is necessary to grind, mix, homogenize and refine all the ingredients into tiny particles (the particle size is not more than 80 microns), and at the same time, make all kinds of different substances mix very evenly, so that you can't tell the characteristics of different substances in the sense of your tongue, but only think that chocolate has become a fine product with seamless lubrication. In order to achieve a high degree of homogeneity, emulsifiers are sometimes added to emulsify and dilute.
The aroma of chocolate is the sensory comprehensive result of aroma and taste. One of the main sources of its aroma is the comprehensive product of cocoa beans after baking and fermentation. According to analysis, the aroma substances of cocoa are composed of hundreds of aromatic compounds, and the special taste of cocoa comes from trace components such as theobromine, caffeine and tannin. During the processing, the presence of sugar and milk increased its burnt taste. The addition of vanillin and maltitol set off and perfected the flavor characteristics of chocolate.
Viscosity is an important physical property of chocolate. Chocolate with melting point above should have good fluidity, so that materials can be transported and operated smoothly. Viscosity is particularly important for the temperature regulation, crystallization and molding of chocolate. Therefore, viscosity is an important technical characteristic of chocolate. The viscosity of chocolate sauce is different at different temperatures, and the viscosity is related to the content of cocoa butter.
The viscosity of chocolate is also controlled by phospholipid, water content, plasmid size of milk solid and dry solid.
At room temperature, chocolate products are hard and brittle. When the temperature exceeds 30℃, it will suddenly change from solid to liquid, losing its luster and complete shape, which is determined by the physical properties of cocoa butter. Chocolate has certain hardness and brittleness below the melting point, and has good fluidity above the melting point.
When it is close to the melting point, the duality of cocoa butter is very obvious. Therefore, the physical properties of chocolate candy are very sensitive when the temperature is close to its melting point. This requires that this characteristic should be paid attention to in the process of mold filling, painting, packaging, storage and transportation.
Production method 1. Preparation of cocoa liquid block:
(1) Baking: The next step of fermented and dried cocoa beans is baking. The main functions of baking are: removing some water; Make the bean shell brittle and dry, which is convenient for shelling; It can turn dark brown cocoa beans into purplish red, make some oil penetrate from cells and make bean meat bright; Baking can change the composition of cocoa beans, gelatinize starch into soluble particles and increase aromatic substances such as acids, alcohols and esters. Make the material plastic.
(2) Different baking methods require different temperatures and time. The new roasting methods are indirect hot air heat transfer and continuous roasting. The baking temperature and time required for different product varieties are different. The technological conditions of the hot air continuous roaster are as follows:
diversification
Temperature℃
Time (minutes)
cocoa powder
125~ 130
25~30
milk chocolate
1 10~ 125
15~20
Dark chocolate
85~ 100
1 1~ 14
The higher the baking temperature, the greater the loss rate of cocoa beans, which is a technical and economic index that needs attention in baking.
(2) Wind separation: Although the shell of roasted cocoa beans has cracked, the meat and shell have not separated yet, and they can be separated by a little rolling. Under the mechanical impact, the beans were broken into irregular pieces. The function of the winnowing screen is to separate the bean meat from the skin, so as to facilitate the processing of the bean meat in the next process.
(3) Grinding: Grinding, also known as primary grinding, is to grind cocoa pieces into paste. This process is very important in order to obtain cocoa mass composed of particles. It is required to grind to 50 ~ 1 14 micron. After one grinding, the time of fine grinding in the next process can be shortened and better results can be obtained. After grinding into paste, brown cocoa liquid can be obtained.
There are many types of primary grinding equipment: disc refiner, roller mill, gear mill, ball mill and colloid mill.
2. Fine grinding: Fine grinding is the process of adding a certain amount of cocoa butter, milk powder, seasonings, surfactants and spices to the cocoa liquid blocks made by primary grinding and the processed sugar powder.
Cocoa or powdered sugar that has only been ground for the first time has large particles, and it has a rough feeling after being imported, so it must be refined to further reduce the particles. When most plasmids are smaller than 25 microns or between 18 ~ 23 microns, chocolate will have no graininess after entering human mouth. This range is the requirement of fine grinding.
Physical changes mainly occur in the process of fine grinding. With fine grinding, the material is dispersed, and the finer the material is dispersed, the larger its surface area is. The total surface area contained in the total volume of a certain number of substances is called specific surface area. The larger the specific surface area, the more chocolate particles, and the smaller and finer the particles.
When maintaining a certain temperature in fine grinding, the finer the fine grinding, the thicker the material, the higher the viscosity and the lower the fluidity.
The refining equipment includes three-roll refiners, five-roll refiners and drum refiners. In the process of fine grinding, we should pay attention to controlling the following operating procedures: adjusting friction gap, adjusting material viscosity, controlling fine grinding temperature and controlling fine grinding degree. There are certain boundary requirements for the particle size of refined chocolate: too large or too many large particles, rough taste; However, if the particle size is too small or the proportion of small particles is too large, it is easy to attach to our tongue and palate, and it is not easy to be taken away from our mouth by saliva, which makes people feel alive.
3. Refinement: Although the finely ground chocolate is very fine, it is not delicate enough and its fragrance is not elegant and mellow enough. Refining can further improve its quality. Especially high-grade chocolate, it needs to be refined.
Refining is carried out in a refiner. There are many kinds of refiners, and the rotary refiner is widely used at present. After repeated friction and collision of the refiner, it is further sharpened and refined to drive away the moisture and volatile smell in the material, so that the material is fully emulsified, thus improving the quality of chocolate.
The main conditions for refining are temperature and time, and the requirements for plasmid angular temperature vary with the variety of chocolate candy. Dark chocolate 55 ~ 85℃; Milk chocolate 45 ~ 60℃. The fine grinding time is long, generally 24 ~ 72 hours.
Refining has the following functions: the quality of chocolate is more delicate and smooth; The material becomes thinner, the fluidity is enhanced, and the color, fragrance and taste are improved.
Phospholipids added in refining are extracted from oils such as soybeans and sunflowers.
Phospholipids have both lipophilic and hydrophilic properties. It has both lipophilic and hydrophilic groups, and its hydrophilic end can also be adsorbed by sugar, cocoa and milk solids. In this way, it plays a surface active role in chocolate materials, making the materials in a highly stable opaque state, so phospholipids also belong to emulsifiers.
Phospholipids can change the interfacial tension between plasmids and reduce the hydration of micelles, thus hindering the formation of gels, playing a dilution role and reducing the viscosity of materials.
Adding phospholipids to chocolate will not reduce the viscosity. Therefore, the addition of chocolate in the production of chocolate candy is between 0. 1-0.5%.
Adding phospholipids to chocolate candy can reduce a certain proportion of cocoa butter, which has certain economic significance.
Phospholipids also have the function of preventing oil oxidation and belong to antioxidants.
4. Temperature adjustment: The function of temperature adjustment is to control the phase transition of cocoa butter at different temperatures, so as to achieve the function of conditioning.
It is best to change the liquid chocolate sauce into solid chocolate candy through the temperature adjustment stage. If the temperature is not adjusted or the temperature is poor, the product quality will be inferior.
According to the requirements of production technology, the chocolate raw material from liquid to solid requires obvious shrinkage, so that it can easily fall off from the mold, which is a necessary requirement of continuous production line. Adjusting the temperature according to the requirements of technological conditions can make chocolate raw materials have obvious shrinkage properties. Conducive to demoulding and continuous production.
Chocolate with no or poor temperature regulation has a rough texture and dark color after cold setting, and lacks the brittle characteristics of chocolate. In the process of preservation, it is easy to become rough and similar to the texture of the nest, and lose the commodity value. Therefore, temperature regulation is an important process in chocolate production.
Chocolate contains about 30% cocoa butter, which is a continuous phase in the dispersion system, and its state determines the physical characteristics of chocolate. The change of chocolate material in temperature regulation is essentially the change of the polymorphic characteristics of cocoa butter. The purpose of temperature adjustment is to make the chocolate raw material produce the highest crystal form, make the chocolate production process smooth and the finished product quality stable.
The refined chocolate is generally above 45℃, and its plasmid is in motion, so it is necessary to stir the materials in the storage tank for a certain period of time before adjusting the temperature.
In the first stage of temperature adjustment, the material was cooled from 45℃ to 29℃, and cocoa butter produced crystal nucleus, which gradually changed into other crystal forms.
In the second stage of temperature adjustment, the material was cooled from 29℃ to 27℃, and some unstable crystal forms were transformed into stable crystal forms, and the quantity and viscosity increased.
In the third stage, the temperature is adjusted, and the material is raised from 27℃ to 29 ~ 30℃, so as to melt the unstable crystal form below 29℃ and only keep the stable crystal form, that is, the crystal form. At the same time, the viscosity of the material is reduced, which is suitable for the requirements of molding process.
The temperature adjustment process is a detailed process, and the temperature adjustment and control must be very strict and accurate. At present, there is no ideal temperature regulator, and the thin film continuous temperature regulator is suitable for mass production.
After adjusting the temperature, chocolate can be used to produce chocolate candy. According to the molding process, chocolate candy can be divided into casting molding and coating molding.
5. Pouring molding: The temperature and viscosity of chocolate for pouring should be strictly controlled. The feeding temperature should be about 30℃, too high temperature will destroy the crystal form of cocoa butter which has formed a stable crystal form. The finished product is loose in texture, lacking in shrinkage characteristics, difficult to demould, and prone to mottling or darkening during storage. When the temperature is too low, the material is sticky, and it is difficult to distribute quantitatively when pouring the mold, and it is difficult to eliminate bubbles in the material, and the product is prone to honeycomb. Therefore, in the molding process, the material should always maintain an accurate temperature and keep it within the minimum temperature difference range.
Viscosity is another important factor for material requirements, and the viscosity of materials also affects its fluidity and distribution accuracy. Therefore, the viscosity range of the material should be maintained during the casting process. After casting the mold, the model should be vibrated to make the quality structure firm and prevent bubbles or gaps. The amplitude is less than 5 mm, and the frequency is about 1000 times per minute.
There are two forms of heat in chocolate sauce: sensible heat and latent heat. Sensible heat refers to the heat released when the temperature of chocolate sauce decreases; Latent heat refers to the heat released from liquid to solid, and the sum of the two kinds of heat is all the heat that needs to be taken away during the molding process.
The requirements for cooling process are as follows: after pouring the mold, put it in a refrigerator at 8 ~ 10℃ for about 5 minutes, and the material temperature will drop to 21℃; After about 265438 0 minutes, the material temperature drops by 65438 02℃, and the total cooling time is 25 ~ 30 minutes. The cooling rate depends on the cooling temperature, cold air mode and product shape.
The cooling speed from liquid to solid should not be too fast, and the cooling temperature is generally 8 ~ 10℃, which can be appropriately increased to 12 ~ 14℃ in the later cooling period. The suitable speed of cold air is 7 meters per second. When the chocolate bar shrinks and deforms, the cooling is over.
6. Coating formation process: The coating forms a candy made of silk, which is called sandwich chocolate. Most of them are named after sandwiches, such as peanut chocolate and protein chocolate.
The coating formation process has the following requirements:
(1) Making and requirements for the heart: the nature, color and fragrance of the heart should be harmoniously combined with the chocolate coat. The specific requirements are that the taste is soft, soluble, non-sticky, and will not cause morphological changes, penetration and perforation, expansion and contraction, rancidity, moth-eaten and mildew. When clothes are coated, the core and temperature are generally about 5℃ lower than the coat temperature.
(2) Preparation of coating and requirements for coating: The cocoa butter in chocolate used for coating is higher than that used for casting. The chocolate sauce used for coating should have proper viscosity and fluidity. Too thick materials are not only inconvenient to transport, but also unevenly distributed, and the coating thickness is uneven, so the consumption quota cannot be guaranteed. During the whole coating process, the temperature adjustment requirements of the sauce should always be strictly controlled at 30 ~ 33℃.
(3) Control the cooling speed: the cooling channel of the coating forming unit should be kept at 7 ~ 12℃, the cold air speed should not exceed 7m/s, and the cooling time should be kept at 15 ~ 20min. The temperature in the later stage of cooling can be slightly higher, and it should be carried out under dry conditions.
7. Chocolate candy packaging: The main functions of packaging are: heat protection, moisture absorption and melting prevention, fragrance escape prevention, grease precipitation and rancidity prevention, mildew prevention, insect prevention and pollution prevention. The requirements for packaging are elegant and colorful, which can keep the color, fragrance, taste and shape of chocolate candy for a long time, especially the sanitary conditions.
General wax paper is difficult to meet the above requirements. Commonly used packaging materials are: aluminum foil, polyethylene, polypropylene, polystyrene and so on. There are also aluminum foil ~ polyethylene composites or other composites.