Chocolate manufacturing process

The first important technical development in the chocolate manufacturing process occurred when water-powered mills superseded the use of manual labor to grind cocoa beans. This led to the establishment of many chocolate factories from 1804 to 1840. Early production consisted entirely of a type of chocolate beverage that was somewhat indigestible since none of the cocoa butter was removed during processing. In 1828, the Dutch firm of Van Houten invented the cocoa press, which facilitated the production of cocoa powder by partial removal of the cocoa butter from beans. 

Vanillin is added, in powder form during the manufacturing process of chocolate, in average amounts of 20 g per 100 kg of the finished product. However, this amount varies according to the quality of the chocolate being made. 

There is no evidence that any of the manufacturers of cocoa and chocolate have adapted any part of the Maillard technology to their manufacturing processes. There are at least two reasons for this. First, the standard processes, as applied to beans of good quality, produce excellent products. Second, while the work just reviewed has given us a rather clear outline as to how chocolate aroma is developed in the roasting of fermented beans, the research work has not yet been done, or reported, that would serve as a basis for improving the industrial processing of cacao beans. 

Cocoa butters have a natural variation in physical properties related to the triacylglycerol structure Malaysian, Indian and Indonesian butters are harder than those from Africa, and Brazilian butters are the softest. The hardness of typical butters from some continents has changed over the years (Timms and Stewart, 1999). Because the hardness affects the processing required for chocolate manufacture, suppliers of cocoa butter to that trade blend butters to attempt to produce a uniform product. 

Non-cocoa fats are added to certain chocolates for a number of reasons. Their introduction was prompted by a sharp rise in the cost of cocoa butter in the 1960s which coincided with the emergence of technologies suitable to analyse butter composition and produce substitute fats. Principally, chocolate manufacture can be made more economical by using more stable processing conditions when other fats are added. The variations in processing required by changes in the chemical composition and physical properties of different batches of cocoa butters, and the effects of erratic harvests, can be ameliorated by the incorporation of the tailored non-cocoa fats. 

Chocolate manufacture is a complicated engineering process with the aim of producing a material which is attractive to the consumer. Critical to the success of processes is the control of the crystalline state of the fats used and the networks that they form (see also Chapters 4 and 17). The engineering challenge is to develop a manufacturing route that produces the required product as efficiently as possible. 

The different tastes and types of chocolate reflect the histories of the industry in different parts of the world, and the tastes of different peoples. A typical composition of chocolate is shown in Table 22.1 and a typical manufacturing process shown in (Beckett 1989), which is the best single reference on chocolate manufacture. The process involves the following steps ... 

Cmde fractions can be obtained by solvent fractionation treatments utilizing lower alcohols, such as ethanol, or alcohol-water mixtures. The product is a soluble fraction rich in phosphatidylcholine, whereas phosphatidic acid and phophatidyli-nositol predominate in the insoluble fraction. The shift in the ratio of phosphatidylcholine to phosphatidylethanolamine improves the emulsification and antispattering capabilities of the soluble fraction. The products of this process can be used as they are or can be further purified with adsorbents. The soluble fraction is an excellent oil-in-water emulsifier and is predominately used in margarine. The acidic phospholipids of the insoluble fraction are used in water-in-oil systems. The chocolate manufacturing industry uses this fraction to increase the viscosity of chocolate masses, thereby reducing the requirement for cocoa butter (83, 84). 

Crystallization events in chocolate manufacture include tempering (pre-crystallization), cooling (bulk crystallization), and bloom (re-crystallization). These processes influence a number of important technological (economic) and sensorial attributes of chocolate (Table 1). Much attention has been focused on bloom formation and its influence on color and gloss, and for good reason, since a consumer may never even buy, let alone eat, a moldy-looking confection. However, we are less... 

The processing of cocoa beans and the manufacturing processes for chocolate and cocoa are shown in Figure 5.46. 

Crystallization Another Important process In chocolate manufacturing is tempering. During the tempering of the chocolate, the temperature of the chocolate is carefully controlled to ensure that the desired crystals form. When chocolate is not properly tempered, crystals form that create poor-quality chocolate. The desired crystals make the chocolate In Figure 2 glossy and firm, and allow it to snap well and melt near body temperature. 

The environmental benefits are (1) enzymes replace hydrochloric acid in the manufacturing process, (2)eUminate the need for harsh chemical processing, (3) reduce the risk to the environment, and (4) provide a safer workplace due to the elimination of the use of a strong acid. The consumer beuefits are (1) confections and specialty baked goods with excellent mouthfeel and taste characteristics are readily available at reasonable cost due to the use of the enzyme invertase (2) soft centers of fine chocolates remain smooth and creamy and (3) some candies stay chewy and soft cookies are available on the grocer s shelves, rivaling homemade versions because of this special food enzyme. 

In certain monocotyledonous families, however, compounds with a 25 configuration were identified [66, 77, 78]. It is interesting to note that (-)-catechin, absent in cocoa beans, is predominant in chocolate, most probably as a result of epimerization of (-)-epicatechin during the manufacturing process [80]. 

At this stage of manufacture, chocolate may be stored for future use in bulk Hquid form if usage is expected to be within one to two weeks, or at 43—50°C in a hot water jacketed agitated tank or in soHd block form where it can be stored for as long as 6 to 12 months. Blocks typically weigh between 3 and 30 kg. Storage conditions for block chocolate should be cool and dry, ie, 7 to 18°C and 40 to 45% relative humidity. If chocolate has been stored in block form, it can be remelted to temperatures up to 50°C and then processed in the same manner as freshly made Hquid chocolate. 

In another method of tempering, soHd chocolate shavings are added as seed crystals to Hquid chocolate at 32—33°C. This is a particularly good technique for a small confectionery manufacturer, who does not produce his own chocolate. However, the shavings are sometimes difficult to disperse and may cause lumps in the finished product (20). Most companies use continuous thin-film heat exchangers for the tempering process. 

Baking chocolate, theobromine and caffeine content, 6 367t Baking enzymes, 10 297 Baking furnaces, 12 734—735 Balanced vinyl chloride processes, in vinyl chloride manufacture, 25 634, 635,... 

The first step in any chemical analysis is procuring a representative sample to measure—a process called sampling. Is all chocolate the same Of course not. Denby and Scott bought one chocolate bar in the neighborhood store and analyzed pieces of it. If you wanted to make broad statements about caffeine in chocolate, you would need to analyze a variety of chocolates from different manufacturers. You would also need to measure multiple samples of each type to determine the range of caffeine in each kind of chocolate. 

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