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Showing posts with label Production. Show all posts
Showing posts with label Production. Show all posts

13 March 2009

Health

While chocolate is regularly eaten for pleasure, there are potential beneficial health effects of eating chocolate. Cocoa or dark chocolate benefits the circulatory system. Other beneficial effects suggested include anticancer, brain stimulator, cough preventor and antidiarrhoeal effects. An aphrodisiac effect is yet unproven.

On the other hand, eating large quantities of any energy-rich food such as chocolate increases risk of obesity. The high amount of calories is caused by factory-added substances such as fat and sugar. The high amounts of added fat and sugar are also suggested to make chocolate so addictive. This is because it is psychologically considered to be unhealthy by most (due to the added sugar and fat), causing a desire to eat chocolate, resulting from restraint. As such, eating black chocolate, or chocolate products with sweeteners, is considered less addictive (and more healthy) than milk chocolate, white chocolate, or any other high-calorie chocolate product.

There is concern of mild lead poisoning for some types of chocolate. Chocolate is toxic to many animals because of insufficient capacity to metabolize theobromine.

A study reported by the BBC indicated that melting chocolate in one's mouth produced an increase in brain activity and heart rate that was more intense than that associated with passionate kissing, and also lasted four times as long after the activity had ended.

Storage

Chocolate is very sensitive to temperature and humidity. Ideal storage temperatures are between 15 and 17 °C (59 to 63 °F), with a relative humidity of less than 50%. Chocolate is generally stored away from other foods as it can absorb different aromas. Ideally, chocolates are packed or wrapped, and placed in proper storage with the correct humidity and temperature. Additionally chocolate is frequently stored in a dark place or protected from light by wrapping paper. Various types of "blooming" effects can occur if chocolate is stored or served improperly. If refrigerated or frozen without containment, chocolate can absorb enough moisture to cause a whitish discoloration, the result of fat or sugar crystals rising to the surface. Moving chocolate from one temperature extreme to another, such as from a refrigerator on a hot day, can result in an oily texture. Although visually unappealing, chocolate suffering from bloom is perfectly safe for consumption.

Tempering

The final process is called tempering. Uncontrolled crystallization of cocoa butter typically results in crystals of varying size, some or all large enough to be clearly seen with the naked eye. This causes the surface of the chocolate to appear mottled and matte, and causes the chocolate to crumble rather than snap when broken. The uniform sheen and crisp bite of properly processed chocolate are the result of consistently small cocoa butter crystals produced by the tempering process.

The fats in cocoa butter can crystallize in six different forms (polymorphous crystallization). The primary purpose of tempering is to assure that only the best form is present. The six different crystal forms have different properties.

  • Crystal Melting temp. Notes
  • I 17 °C (63 °F) Soft, crumbly, melts too easily.
  • II 21 °C (70 °F) Soft, crumbly, melts too easily.
  • III 26 °C (78 °F) Firm, poor snap, melts too easily.
  • IV 28 °C (82 °F) Firm, good snap, melts too easily.
  • V 34 °C (94 °F) Glossy, firm, best snap, melts near body temperature (37 °C).
  • VI 36 °C (97 °F) Hard, takes weeks to form.

Making chocolate considered "good" is about forming as many type V crystals as possible. This provides the best appearance and texture and creates the most stable crystals so the texture and appearance will not degrade over time. To accomplish this, the temperature is carefully manipulated during the crystallization.

Generally, the chocolate is first heated to 45 °C (115 °F) to melt all six forms of crystals. Next, the chocolate is cooled to about 27 °C (80 °F), which will allow crystal types IV and V to form. At this temperature, the chocolate is agitated to create many small crystal "seeds" which will serve as nuclei to create small crystals in the chocolate. The chocolate is then heated to about 31 °C (88 °F) to eliminate any type IV crystals, leaving just type V. After this point, any excessive heating of the chocolate will destroy the temper and this process will have to be repeated. However, there are other methods of chocolate tempering used. The most common variant is introducing already tempered, solid "seed" chocolate. The temper of chocolate can be measured with a chocolate temper meter to ensure accuracy and consistency. A sample cup is filled with the chocolate and placed in the unit which then displays or prints the results.

Two classic ways of manually tempering chocolate are:

* Working the molten chocolate on a heat-absorbing surface, such as a stone slab, until thickening indicates the presence of sufficient crystal "seeds"; the chocolate is then gently warmed to working temperature.
* Stirring solid chocolate into molten chocolate to "inoculate" the liquid chocolate with crystals (this method uses the already formed crystal of the solid chocolate to "seed" the molten chocolate).

Chocolate tempering machines (or temperers) with computer controls can be used for producing consistently tempered chocolate, particularly for large volume applications.

Conching

The penultimate process is called conching. A conche is a container filled with metal beads, which act as grinders. The refined and blended chocolate mass is kept in a liquid state by frictional heat. Chocolate prior to conching has an uneven and gritty texture. The conching process produces cocoa and sugar particles smaller than the tongue can detect, hence the smooth feel in the mouth. The length of the conching process determines the final smoothness and quality of the chocolate. High-quality chocolate is conched for about 72 hours, lesser grades about four to six hours. After the process is complete, the chocolate mass is stored in tanks heated to approximately 45–50 °C (113–122 °F) until final processing.

Blending

Chocolate liquor is blended with the cocoa butter in varying quantities to make different types of chocolate or couvertures. The basic blends of ingredients for the various types of chocolate (in order of highest quantity of cocoa liquor first), are as follows:

* Dark chocolate: sugar, cocoa butter, cocoa liquor, and (sometimes) vanilla
* Milk chocolate: sugar, cocoa butter, cocoa liquor, milk or milk powder, and vanilla
* White chocolate: sugar, cocoa butter, milk or milk powder, and vanilla

Usually, an emulsifying agent such as soy lecithin is added, though a few manufacturers prefer to exclude this ingredient for purity reasons and to remain GMO free, sometimes at the cost of a perfectly smooth texture. Some manufacturers are now using PGPR, an artificial emulsifier derived from castor oil that allows them to reduce the amount of cocoa butter while maintaining the same mouthfeel.

The texture is also heavily influenced by processing, specifically conching (see below). The more expensive chocolate tends to be processed longer and thus have a smoother texture and "feel" on the tongue, regardless of whether emulsifying agents are added.

Different manufacturers develop their own "signature" blends based on the above formulas, but varying proportions of the different constituents are used.

The finest, plain dark chocolate couvertures contain at least 70% cocoa (both solids and butter), whereas milk chocolate usually contains up to 50%. High-quality white chocolate couvertures contain only about 33% cocoa.

Producers of high quality, small batch chocolate argue that mass production produces bad quality chocolate. Some mass-produced chocolate contains much less cocoa (as low as 7% in many cases) and fats other than cocoa butter. Vegetable oils and artificial vanilla flavor are often used in cheaper chocolate to mask poorly fermented and/or roasted beans.

In 2007, the Chocolate Manufacturers Association in the United States, whose members include Hershey, Nestlé, and Archer Daniels Midland, lobbied the Food and Drug Administration to change the legal definition of chocolate to let them substitute partially hydrogenated vegetable oils for cocoa butter in addition to using artificial sweeteners and milk substitutes. Currently, the U.S. Food and Drug Administration (FDA) does not allow a product to be referred to as "chocolate" if the product contains any of these ingredients.

Processing

Cacao pods are harvested by cutting the pods from the tree using a machete, or by knocking them off the tree using a stick. The beans with their surrounding pulp are removed from the pods and placed in piles or bins to ferment. The fermentation process is what gives the beans their familiar chocolate taste. It is important to harvest the pods when they are fully ripe because if the pod is unripe, the beans will have a low cocoa butter content, or there will be insufficient sugars in the white pulp for fermentation, resulting in a weak flavor. After fermentation, the beans must be quickly dried to prevent mold growth. Climate and weather permitting, this is done by spreading the beans out in the sun from 5 to 7 days.

The dried beans are then transported from the plantation where they were grown to a chocolate manufacturing facility. The beans are then cleaned (removing twigs, stones, and other debris), roasted, and graded. Next the shells are removed to extract the nib. Finally, the nibs are ground and liquified, resulting in pure chocolate in fluid form: chocolate liquor. The liquor can be further processed into two components: cocoa solids and cocoa butter.

Cacao varieties

Cacao trees are small, understory trees that need rich, well-drained soils. They naturally grow within 20 degrees of either side of the equator because they need about 2000 millimeters of rainfall a year, and temperatures in the range of 21 to 32 degrees Celsius. Cacao trees cannot tolerate a temperature lower than 15 degrees Celsius (59 degrees Fahrenheit).

The three main varieties of cacao beans used in chocolate are criollo, forastero and trinitario.

Representing only five percent of all cocoa beans grown, criollo is the rarest and most expensive cocoa on the market and is native to Central America, the Caribbean islands and the northern tier of South American states. There is some dispute about the genetic purity of cocoas sold today as Criollo, as most populations have been exposed to the genetic influence of other varieties. Criollos are particularly difficult to grow, as they are vulnerable to a variety of environmental threats and produce low yields of cocoa per tree. The flavor of Criollo is described as delicate yet complex, low in classic chocolate flavor, but rich in "secondary" notes of long duration.

The most commonly grown bean is forastero, a large group of wild and cultivated cacaos, most likely native to the Amazon basin. The African cocoa crop is entirely of the Forastero variety. They are significantly hardier and of higher yield than Criollo. The source of most chocolate marketed, forastero cocoas are typically strong in classic "chocolate" flavor, but have a short duration and are unsupported by secondary flavors, producing "quite bland" chocolate.

Trinitario is a natural hybrid of Criollo and Forastero. Trinitario originated in Trinidad after an introduction of Forastero to the local Criollo crop. Nearly all cacao produced over the past five decades is of the Forastero or lower-grade Trinitario varieties.

Production Of Chocolate

Roughly two-thirds of the entire world's cocoa is produced in Western Africa, with 43% sourced from Côte d'Ivoire. According to the World Cocoa Foundation, some 50 million people around the world depend on cocoa as a source of livelihood. The industry is dominated by three chocolate makers, Barry Callebaut, Cargill and Archer Daniels Midland Company. In the UK, most chocolatiers purchase their chocolate from them, to melt, mold and package to their own design. Despite some disagreement in the EU about the definition,[clarification needed] chocolate is any product made primarily of cocoa solids and cocoa fat. The different flavors of chocolate can be obtained by varying the time and temperature when roasting the beans, by adjusting the relative quantities of the cocoa solids and cocoa fat, and by adding non-chocolate ingredients.[citations needed]

Production costs can be decreased by reducing cocoa solid content or by substituting cocoa butter with a non-cocoa fat. Cocoa growers object to allowing the resulting food to be called "chocolate", due to the risk of lower demand for their crops.

There are two main jobs associated with creating chocolate candy, chocolate makers and chocolatiers. Chocolate makers use harvested cacao beans and other ingredients to produce couverture chocolate. Chocolatiers use the finished couverture to make chocolate candies (bars, truffles, etc.).
 
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