Cocoa roasting

Meat products, e.g. beef, chicken, pork, lamb Vegetables, e.g. onions, potatoes, garlic Roasted products, e.g. coffee, cocoa, roasted nuts, popcorn Cereal products, e.g. biscuits, bread, extrudates Beverages, e.g. beer, wine, whiskey... 

Another possibility for the use of flash pyrolysis is to bring smaller scale plants into the market. Thinkable are plants with a capacity of 1-10 t/d max.. There are a lot of biomass processing companies with a more or less unusual biomass waste fraction. This waste has no value for these companies at the moment, it only entails disposal costs. It will be demonstrated that these biomass can lead to acceptable bio-oil yields In this study cocoa shell from a German cocoa roasting company with an output of 4-S t coca shell per day was investigated. 

The flavor in water is cocoa, nutty (Pittet and Hruza, 1974), also described as cocoa, roasted-toasted, slightly liquorice at a concentration of lppm (Chemisis, 1993). A threshold of 1.8-7.2 p-g/m3 air was found by Gasser and Grosch (1990). 

Ikrawan, Y., S. Chaiseri, O. Vungdeethum, Effect of fermentation time on pyrazine concentration of Thai Forasero beans. Kasetsart J. Natural ScL, 1997. 31, 4, p. 479. Mermet, G., E. Cros, G. Georges, Preliminary study to optimize cocoa roasting parameters aroma precursor consumption, pyrazine development, organoleptic quality. Cafe Cacao, 1992. 36, 4, p. 285. 

Pyrazine derivatives (alkylpyrazines, acylpyrazines, aJkoxypyrazines and other derivatives, 8-175) are present in virtually all heat processed foods (such as meat, bread, cocoa, roasted coffee and nuts), where they are the major carriers of the characteristic burnt, roasted and nutty odour. Pyrazines arise mostly as products of the Madlard reaction and by pyrolysis of some amino acids. 2-Alkyl-3-methoxypyrazines, which are odour components ofvarious vegetables, are formed as primary odorous compounds through enzymatic reactions. 

A more complex flavor development occurs in the production of chocolate. The chocolate beans are first fermented to develop fewer complex flavor precursors upon roasting, these give the chocolate aroma. The beans from unfermented cocoa do not develop the chocolate notes (84—88) (see Chocolate and cocoa). The flavor development process with vanilla beans also allows for the formation of flavor precursors. The green vanilla beans, which have Htfle aroma or flavor, are scalded, removed, and allowed to perspire, which lowers the moisture content and retards the enzymatic activity. This process results in the formation of the vanilla aroma and flavor, and the dark-colored beans that after drying are the product of commerce. 

Cocoa beans are sometimes evaluated in the laboratory to distinguish and characterize flavors. Beans are roasted at a standardized temperature for a specific period of time, shelled, usually by hand, and ground or heated slightly to obtain chocolate Hquor. The Hquor s taste is evaluated by a panel of... 

Blending. Most chocolate and cocoa products consist of blends of beans chosen for flavor and color characteristics. Cocoa beans may be blended before or after roasting, or nibs may be blended before grinding. In some cases finished Hquors are blended. Common, or basic beans, are usually African or BraziUan and constitute the bulk of most blends. More expensive flavor beans from Venezuela, Trinidad, Ecuador, etc are added to impart specific characteristics. The blend is deterrnined by the end use or type of product desired. 

The natural moisture of the cocoa bean combined with the heat of roasting cause many chemical reactions other than flavor changes. Some of these reactions remove unpleasant volatile acids and astringent compounds, partially break down sugars, modify tannins and other nonvolatile compounds with a reduction in bitterness, and convert proteins to amino acids that react with sugars to form flavor compounds, particularly pyrazines (4). To date, over 300 different compounds, many of them formed during roasting, have been identified in the chocolate flavor (5). 

Table 4. Analyses of Cocoa Shell from Roasted Cocoa Beans...

The FDA has not legally defined cocoa butter, and no standard exists for this product under the U.S. Chocolate Standards. For the purpose of enforcement, the FDA defines cocoa butter as the edible fat obtained from cocoa beans either before or after roasting. Cocoa butter as defined in the US. Pharmacopeia is the fat obtained from the roasted seed of Theohroma cacao Uinne. 

Caffeine consumption is primarily due to coffee, tea and soft drinks. In the U.S., it is estimated that coffee contributes to 75% of the total caffeine intake, tea is 15%, and soda with caffeine accounts for 10% 5 chocolate and other caffeine-containing foods and medications contribute relatively little to overall caffeine exposure. Caffeine also varies by sources tea leaves contain 1.5 to 3.5% caffeine kola nuts contain 2% caffeine and roasted coffee beans contain 0.75 to 1.5% caffeine.6 Coffee varies in caffeine content some analyses have estimated that caffeine may range from 0.8 to 1.8%, depending on the type of coffee.7 Crops of coffee, tea, and cocoa are very similar in their production periods and their useful life in production. Typically coffee, tea, and cocoa trees can be productive with crops every 5 years for a total period of 40 years,8 or an estimated 8 yields per tree. 

Cocoa-purple, in cocoa shell from roasted beans, 6 357t... 

L-ascorbic acid and, 25 751 as chelating agent, 5 731 in cocoa shell from roasted beans, 6 357t Oxalic-acid-catalyzed novolacs, in molding compounds, 75 786 Oxalic acid esterification, 72 652 Oxaloacetic acid, in citric acid cycle, 6 633 Oxalosuccinic acid, in citric acid cycle, 6 633... 

Star-branched butyl rubber, 4 437-438 copolymers, 4 445-446 Starch(es), 4 703-704, 20 452-453 as blood substitute, 4 111-112 cationic, 18 114-115 in cereal grains, 26 271-274 in cocoa shell from roasted beans, 6 357t compression effects in centrifuges, 5 513 depolymerization, 4 712 in ethanol fermentation, 10 534—535 etherified, 20 563 as a flocculant, 11 627 high-amylose, 26 288 Mark-Houwink parameters for, 20 558t modified and unmodified, 12 52-53 in paper manufacture, 18 122-123 performance criteria in cosmetic use, 7 860t... 

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