Chocolate roasting

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. 

A wide variety of special malts are produced which impart different flavor characteristics to beers. These malts are made from green (malt that has not been dried) or finished malts by roasting at elevated temperatures or by adjusting temperature profiles during kilning. A partial Hst of specialty malts includes standard malts, ie, standard brewers, lager, ale, Vienna, and wheat caramelized malts, ie, Munich, caramel, and dextrine and roasted products, ie, amber, chocolate, black, and roasted barley. 

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). 

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. 

Sweet chocolate can contain milk or milk soHds (up to 12% max), nuts, coffee, honey, malt, salt, vanillin, and other spices and flavors as well as a number of specified emulsifiers. Many different kiads of chocolate can be produced by careful selection of bean blends, controlled roasting temperatures, and varying amounts of ingredients and flavors (20). 

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. 

I thought, I d ask for a magic carpet like Aladdin so I could fly around the world and find my father s pictures, but I said my usual answer instead Roast chicken and lots of chocolate cake. And a puppy. ... 

A friend once ate at a banquet hosted by the New York Entomological Society where the menu included chocolate cricket torte, mealworm ganoush, sauteed Thai water bugs, and waxworm fritters with plum sauce. He mentioned a movie theater in Colombia where roasted ants were eaten like popcorn. As delicious as these treats were, his favorites were honeypot ants, with their transparent abdomens distended with peach nectar. 

Pyrazines are mainly used in roasted, peanut and chocolate flavours. Alkyl pyrazines can be obtained by the reaction in an autoclave at high temperature (120-160 °C) of reducing sugars like rhamnose and ammonia. 

The mycotoxin ochratoxin A (AAA) (7), which is a possible human carcinogen, continues to receive extensive attention due to its presence in a myriad of foods and beverages (1520, 1521) and its well-established toxicity (teratogenicity, mutagenicity, immunotoxicity, genotoxicity, and carcinogenicity) (1522-1524). Major sources of ochratoxin A are grapes, must, and wine (1525-1533), cereals (1534), beer (1535,1536), dried fruit (1537), roasted coffee (1538), and cocoa products and chocolate (1539). 

Catechin and the proanthocyanidin prodelphinidin B3 are, respectively, the major monomeric and dimeric flavan-3-ols found in barley and malt where prodelphinidin B3 is the main contributor for the radical scavenging activity [Dvorakova et al., 2007], Proanthocyanidins have also been detected in nuts. Hazelnuts (Corylus avellana) and pecans (Carya illinoensis) are particularly rich in proanthocyanidins containing ca. 5 g kg, whereas almonds (Prunus dulcis) and pistachios (Pistachio vera) contain 1.8-2.4 mg kg 1, walnuts (Juglans spp.) ca. 0.67 g kg, roasted peanuts (Arachis hypgaea) 0.16 g kg, and cashews (Anarcardium occidentale) 0.09 g kg 1 [Crozier et al., 2006c]. Dark chocolate derived from the roasted seeds of cocoa (Theobroma cacao) is also a rich source of procyanidins [Gu et al., 2004], Monomeric flavan-3-ols and the proanthocyanidin B2, B5 dimers, and Q trimer are found in fresh cocoa beans (Fig. 1.13). Flavan-3-ols have also been detected in mint... 

Although cocoa as a drink is now rather unfashionable, it provides the raw material for the manufacture of chocolate and is commercially very important. Cocoa (or cacao) is derived from the roasted seeds of Theobroma cacao (Sterculiaceae), a tree widely cultivated in South America and West Africa. The fruits develop on the trunk of the tree, and the seeds from them are separated, allowed to ferment, and are then roasted to develop the characteristic chocolate flavour. The kernels are then separated from the husks, ground up, and processed in various ways to give chocolate, cocoa, and cocoa butter. 

Cocoa seeds contain 35-50% of oil (cocoa butter or theobroma oil), 1-4% theobromine and 0.2-0.5% caffeine, plus tannins and volatile oils. During fermentation and roasting, most of the theobromine from the kernel passes into the husk, which thus provides a convenient source of the alkaloid. Theobroma oil or cocoa butter is obtained by hot expression from the ground seeds as a whitish solid with a mild chocolate taste. It is a valuable formulation aid in pharmacy where it is used as a suppository base. It contains glycerides of oleic (35%), stearic (35%), palmitic (26%), and linoleic (3%) acids (see page 44). 

T at 2 ppm Sweet, roasted meat-like, roasted nut-like, chocolate-like, vegetable green-like, hydrolyzed vegetable protein-like. 

Many bland, or even downright unpleasant-tasting, substances are transformed into some of the most desirable flavors and popular foods by roasting. Thus, those foods, representing such different tastes and aromas as chocolate, bread, roast beef, coffee, and toasted nuts have in common the fact that they are products of the Maillard browning... 

Rohan had suggested that the operative reaction in the development of chocolate aroma might be a Strecker degradation of the amino acid fraction. Bailey et al. (8) demonstrated quantitatively that three aldehydes, which could be related to leucine, valine, and alanine, were prominent in the volatiles from a typical sample of roasted, ground cacao beans. 

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. 

But the human nose has no difficulty in distinguishing chocolate from roast beef, and the flavor chemist is trying to catch up with this degree of discrimination. 

Chocolate has antioxidant properties for low-density lipoproteins and hence could prevent heart disease. Foods and beverages derived from cocoa beans have been consumed by humans since 460 a.d. Cocoa pods from the cocoa tree (Theobroma cacao) are harvested and the beans removed and fermented. Dried and roasted beans contain about 300 chemicals including caffeine, theobromine, and phenethylamine. Chocolate liquor is prepared by finely grinding the nib of the cocoa bean and is the basis for all chocolate products. Cocoa powder is made by removing part of the cocoabutter from the liquor. Bittersweet chocolate, sometimes called dark chocolate, contains between 15 and 60% chocolate liquor, the remainder being cocoa butter, sugar, and other additives. Milk chocolate is the predominant form of chocolate consumed in the U.S. and typically contains 10 to 12% chocolate liquor. 

Chocolate is a solid-in-oil (S/O) suspension of non-fat partides (of about 10-100 (im diameter) of sugar and cocoa (cacao) in a continuous phase of cocoa butter, which is the natural fat from the cocoa bean [215]. When cocoa beans are cleaned, roasted, cracked and ground, chocolate liquor results, a suspension of cocoa powder in cocoa butter. Depending on how much cocoa butter is removed (by pressing) one can make, in decreasing order of cocoa butter content bitter, unsweetened, baking... 

Numerous y- and 8-lactones were identified in Tokaji aszu grapes (Miklosy and Kerenyi, 2004 Miklosy et al., 2004). The odor notes of the y-lactones were described as resin- and caramel-like, roasted, or honey, while the 8-lactones exhibited characteristic notes of coconut, chocolate, and peach. The same lactones had been identified earlier from botrytized wines but not from normal wines (Schreier et al., 1976). Lactones are mostly found in oxidatively aged wines but seem to develop in fruit due to the oxidizing effect of B. cinerea, water loss, or Maillard reactions (Miklosy et al., 2004). 

Cacao Nibs Cacao nibs are crushed bits of cacao beans—which are actually not beans at all, but seeds from the Theobroma plant. Most often, these beans are dried or roasted and then extracted to make cocoa butter for chocolate, or ground into powder to make cocoa powder. Cacao nibs are crushed cacao beans that have not been made into chocolate or cocoa powder. You can find them raw or roasted, and they resemble espresso beans in texture and crunch. They contain no added sugar, so they re bittersweet. They add great texture to cookies—I even use them as a topping for ice cream. They can be found at most specialty and health-food stores or online. Make sure you buy the finely ground variety. 

One o-f the world s most popular -flavors, chocolate, is a product o-f both -fermentation and roasting. Early studies by Rohan (44-47) pointed out the importance o-f liberating the precusor materials (amino acid) so that roasting will generate chocolate aroma. 

Some 350 other volatiles have been identified in chocolate aroma, and about 10% are pyrazines (48— 51) and quinoxalines (52). During roasting 49% of the total free amino acids are lost with only 4% of the bound amino acid being lost (53). 

Besides their general flavor forming potential peptides are also reported to be unique precursors of composite food aromas. Peptides formed in the fermentative stage of cacao processing have been linked to roast generated chocolate aroma (5). Also, a methionine rich polypeptide has been associated vith roasted peanut volatiles (15). 

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