Chocolate!! Your mouth must have started to water after hearing this word. Chocolate is one such product, which is loved by all age groups. There are so many memories connected with chocolate from our childhood. If you are happy or sad, having a piece of chocolate can make everything seem better. But, the chocolate we eat, the taste we remember is not readily available in the nature. It is achieved by passing the cocoa beans through a number of processes which help in achieving the authentic taste of chocolate.
Cocoa beans are the beans of the Theobroma cacao L. tree. There are four types of cacao- Forastero, Criollo, Trinitario, Nacional. Out of these four types Forastero variety is used widely and it accounts for 95% of world cocoa production (Mattia et al., 2017). Cocoa beans are enclosed in a melon shaped shell called cacao pods. Each cacao pod has around 30-40 beans covered with pulp. This pulp plays a significant role in contributing the characteristic flavour of chocolate. So, how do these cocoa beans from cacao pods form the chocolate we all love? Let’s cherish this beautiful journey of chocolate from farm to our palates.
While producing chocolate, every step has its own contribution towards attaining the desired texture and flavour of chocolate. How? Stay tuned to find out.
Harvesting cacao pods-
Cacao pods turn vibrant yellow/orange upon ripening. Once they are ripened they are plucked from the tree and are opened up within a period of 4 days. Then the seeds are removed in the baskets and carried to a dry place.
Initiating the flavour development with fermentation-
Fermentation is the next step. This is the most important step as it is responsible for formation of the certain precursors of chocolate flavour. The pulp surrounding the cocoa beans is fermented by microorganisms along with the rise in temperature. This pulp contains sugar, which is utilized by yeast and bacteria. As a result, heat is generated and the temperature rises to about 500C, which causes the pulp to liquefy and drain out. This process can last from 5 to 10 days (Mattia et al., 2017). Usually two methods are used for this step. One is where a heap of cocoa beans is formed and covered with banana leaves with stirring and mixing at regular intervals for aeration and increasing the microbial activity. In second method, boxes with perforated bottom are used. As a result of this process the colour of cocoa beans changes and flavours are developed.
Drying the beans-
Fermented beans are then dried using sun drying method or heating trays. The aim of this process is to reduce the moisture content below 7% (Mattia et al., 2017). After drying, the beans are sorted and packed for further processing.
Cocoa beans are roasted in order to get the authentic chocolate flavour, aroma and colour which is there in the form of precursors generated during the fermentation process (Barisic et al., 2019).. Roasting is done at 120–150°C for 5–120 min. Roasting makes the shell of cocoa bean brittle and these shells are separated by winnowing. Along with developing the flavour, it also reduces the moisture content to below 2% and the number of microorganisms (Shafi et al., 2018). After roasting, nibs become darker in colour. The proteins are denatured and degenerated. Also, the amount of volatile acids and substances responsible acidity and bitterness are reduced (Albandary et al., 2022).
Grinding cocoa nibs-
After winnowing cacao shells are removed and only cocoa nibs pass to the grinding stage. The purpose of this stage is to form cocoa liquor/cocoa mass. For grinding cocoa nibs various machines like stone mills, disc mills, pin or hammer mills and bead or ball mills are used. Cocoa nib consists of almost 55% of cocoa butter. Grinding is a multistage process and the heat generated during the process causes the cocoa butter to melt and form cocoa liquor. Refined cocoa liquor is stored in the storage tank and heated to 90-100 °C for microbial destruction and aging. Almost 78-90% cocoa butter is extracted using the pressing method and for extracting the remaining fat supercritical fluid extraction can be used (Shafi et al., 2018).
The cocoa mass/liquor contains nearly equal amount of cocoa butter and cocoa solids. By further pressing of the cocoa mass, coco butter and coco powder can be obtained. These are the main ingredients required for making a chocolate. Now that our ingredients are ready lets see how the actual chocolate is formed.
Chocolate manufacturing (Shafi et al., 2018 & Albandary et al., 2022)-
Mixing and refining-
Mixing of ingredients in chocolate manufacturing is very important. Continuous or batch processing at proper time-temperature (40-50 ºC for 12-15 minutes) is used for mixing the ingredients in an automated kneader until a tough and plastic texture is achieved. There are many types of chocolates like millk chocolate(Coco mass + Coco butter + Sugar + Milk powder), dark chocolate (Coco mass + Coco butter + Sugar), white chocolate (Milk powder + Coco butter + Sugar). So, the ingredients used vary depending upon the chocolate being produced.
Refining of chocolate is important for achieving smooth texture by achieving a particle size less than 30 μm. Particle size influences the rheology as well as sensory attributes of the chocolate.
Conching is a process, which involves agitation of the chocolate mix at a temperature above 50ºC for few hours. It is an important step in the chocolate manufacturing, which is required for attaining viscosity, flavour, texture. Conching helps in the removal of volatile acids and moisture and also helps in reducing viscosity. For this process, the equipment used is called a conch. Conch consists of a mixer blade, which exerts shear force and aids in mixing. The time and temperature combination for conching may vary depending upon the desired end product. For enhancing the viscosity of chocolate for tempering, soy lecithin can be added towards the end of conching.
Tempering and moulding-
Now the chocolate is ready and it has to be formed into bars. But just pouring the chocolate into moulds will not form the chocolate that we all love. Chocolate contains cocoa butter, which can crystallize into different forms upon cooling. This is called as polymorphism. Cocoa butter can exist typically in six different crystalline forms. But all the forms are not desirable and stable; only small crystals which can melt in our mouth upon eating and release flavour are desirable.
Sometimes when we break chocolate it crumbles or takes a longer time to melt in our mouth, it is due to uncontrolled crystallization. It can result in larger crystals, which will cause the chocolate to crumble upon breaking and a matt surface. Hence the purpose of tempering is to make sure that only best type of crystals are present. In simple words, tempering is controlled heating and cooling process for achieving the desirable crystals.
The tempered chocolate is then poured into the moulds of desired shapes and allowed to harden. Now the chocolate is ready.
Once the chocolate is ready, it is very important to store the chocolate properly. Chocolate contains fats and sugar which can melt when exposed to heat and moisture respectively. So, if the storage conditions are too hot or too humid a white, dusty, grainy coat on chocolate. It is known as fat bloom and sugar bloom. Also, improper tempering can be one of the cause for these defects. So, should you throw away your chocolate if you find a whitish layer or no glaze on your chocolate? No, these defects are not harmful but they can make the chocolate unappealing.
Chocolate travels a very long distance before reaching our palates. A lot of processing methods are responsible for achieving that authentic and significant chocolate flavour. Temperature plays important role in many steps of chocolate manufacturing. A“good chocolate” is the one which has a gloss, breaks easily and melts effortlessly when we put it on our tongue. So, indulge into your favourite chocolate and appreciate the efforts put in for making it.
- Albandary, A., Albandary, F., & Jaiswal, A. K. (2022). Chocolate: Health, Processing, and Food Safety. In I. Var, & S. Uzunlu (Eds.), A Glance at Food Processing Applications [Working Title]. IntechOpen. https://doi.org/10.5772/intechopen.104819
- Di Mattia, C. D., Sacchetti, G., Mastrocola, D., & Serafini, M. (2017). From Cocoa to Chocolate: The Impact of Processing on In Vitro Antioxidant Activity and the Effects of Chocolate on Antioxidant Markers In Vivo. Frontiers in Immunology, 8. doi:10.3389/fimmu.2017.01207
- Shafi, Farah & Reshi, Monica & Bashir, Iqra. (2018). CHOCOLATE PROCESSING. IJABR, VOL.8 (3) 2018: 408-419. https://www.researchgate.net/publication/330171165_CHOCOLATE_PROCESSING