Conche

Last updated
Conche (in the Imhoff-Schokoladenmuseum)
Granite roller and granite base of a conche Granite Roller and Granite Base of a Conche.jpg
Granite roller and granite base of a conche

A conche is a surface scraping mixer and agitator that evenly distributes cocoa butter within chocolate and may act as a "polisher" of the particles. [1] It also promotes flavor development through frictional heat, release of volatiles and acids, and oxidation. There are numerous designs of conches. Food scientists are still studying precisely what happens during conching and why. The name arises from the shape of the vessels initially used which resembled conch shells.

Contents

When ingredients are mixed in this way, sometimes for up to 78 hours, chocolate can be produced with a mild, rich taste. Lower-quality chocolate is conched for as little as 6 hours. Since the process is so important to the final texture and flavor of chocolate, manufacturers keep the details of their conching process proprietary. [2]

Rodolphe Lindt invented the "conche" in Berne, Switzerland, in 1879. It produced chocolate with superior aroma and melting characteristics compared to other processes used at that time. The Lindt chocolate company states that Lindt (perhaps mistakenly) allowed a mixer containing chocolate running over a weekend (or possibly overnight, according to other variants of the possibly-apocryphal story). [3] Upon returning to the device, Lindt recognised the final product to have different properties to conventionally-produced chocolate at the time, with a less granular texture and greater shine than conventional chocolate at the time lacked, being generally "gritty" when solidified owing to the presence of non-ideal cocoa butter crystals. Lindt's invention made the mass-production of chocolate bars more practical, eventually replacing chocolate beverages as the primary means of mass chocolate consumption. [4]

Lindt's original conche consisted of a granite roller and granite trough; such a configuration is now called a "long conche" and can take more than a day to process a tonne of chocolate. The ends of the trough were shaped to allow the chocolate to be thrown back over the roller at the end of each stroke, increasing the surface area exposed to air. A modern rotary conche can process 3 to 10 tonnes of chocolate in less than 12 hours. Modern conches have cooled jacketed vessels containing long mixer shafts with radial arms that press the chocolate against vessel sides. A single machine can carry out all the steps of grinding, mixing, and conching required for small batches of chocolate.

Conching process

A Hershey conche from the early 1900s, on display as part of the Hershey Story collection Hershey Conche.jpg
A Hershey conche from the early 1900s, on display as part of the Hershey Story collection

Conching redistributes the substances from the dry cocoa that create flavor into the fat phase. Air flowing through the conche removes some unwanted acetic, propionic, and butyric acids from the chocolate and reduces moisture. A small amount of moisture greatly increases viscosity of the finished chocolate, so machinery is cleaned with cocoa butter instead of water. [5] Some of the substances produced in roasting of cocoa beans are oxidized in the conche, mellowing the flavor of the product.

The temperature of the conche is controlled and varies for different types of chocolate. Generally, higher temperature leads to a shorter required processing time. Temperature varies from around 49 °C (120 °F) for milk chocolate to up to 82 °C (180 °F) for dark chocolate. The elevated temperature leads to a partially caramelized flavor and in milk chocolate promotes the Maillard reaction. [1]

The chocolate passes through three phases during conching. In the dry phase the material is in powdery form, and the mixing coats the particles with fat. Air movement through the conche removes some moisture and volatile substances, which may give an acidic note to the flavor. Moisture balance affects the flavor and texture of the finished product because, after the particles are coated with fat, moisture and volatile chemicals are less likely to escape. [4]

In the pasty phase more of the particles are coated with the fats from the cocoa. The power required to turn the conche shafts increases at this step.

The final liquid phase allows minor adjustment to the viscosity of the finished product by addition of fats and emulsifiers, depending on the intended use of the chocolate.

While most conches are batch-process machines, continuous-flow conches separate the stages with weirs, over which the product travels through separate parts of the machine. [4] A continuous conche can reduce the conching time for milk chocolate to as little as four hours. [5]

See also

Related Research Articles

Chocolate Food produced from the seed of Theobroma cacao

Chocolate is a preparation of roasted and ground cacao seeds that is made in the form of a liquid, paste, or in a block, which may also be used as a flavoring ingredient in other foods. The earliest signs of use are associated with Olmec sites suggesting consumption of chocolate beverages, dating from 19 centuries BCE. The majority of Mesoamerican people made chocolate beverages, including the Maya and Aztecs. The word chocolate is derived from the Spanish word chocolate, deriving in turn from the Classical Nahuatl word xocolātl.

Nutella is a brand of sweetened hazelnut cocoa spread. Nutella is manufactured by the Italian company Ferrero and was first introduced in 1964, although its first iteration dates to 1963.

Candy Sweet confection

Candy, also called sweets or lollies, is a confection that features sugar as a principal ingredient. The category, called sugar confectionery, encompasses any sweet confection, including chocolate, chewing gum, and sugar candy. Vegetables, fruit, or nuts which have been glazed and coated with sugar are said to be candied.

Chocolate milk Sweetened chocolate-flavored milk

Chocolate milk is a sweetened chocolate-flavored milk. It can be made by mixing chocolate syrup with milk. It can be purchased pre-mixed with milk or made at home by blending milk with cocoa powder and a sweetener, melted chocolate, chocolate syrup, or a pre-made powdered chocolate milk mix. Other ingredients, such as starch, salt, carrageenan, vanilla, or artificial flavoring are sometimes added. To add nutritional value to the product, sometimes some minerals like zinc oxide or iron are added.

Animal fat Fats and oils which are derived from animals

Animal fats and oils are lipid materials derived from animals. Physically, oils are liquid at room temperature, and fats are solid. Chemically, both fats and oils are composed of triglycerides. Although many animal parts and secretions may yield oil, in commercial practice, oil is extracted primarily from rendered tissue fats obtained from livestock animals like pigs, chickens and cows. Dairy products also yield popular animal fat and oil products such as cheese, butter, and milk.

Ghee

Ghee is a class of clarified butter that originated in ancient India. It is commonly used in cuisine of the Indian subcontinent, Middle Eastern cuisine, Southeast Asian cuisine, traditional medicine, and religious rituals.

Cocoa butter Pale-yellow, edible fat extracted from the cocoa bean

Cocoa butter, also called theobroma oil, is a pale-yellow, edible fat extracted from the cocoa bean. It is used to make chocolate, as well as some ointments, toiletries, and pharmaceuticals. Cocoa butter has a cocoa flavor and aroma. Its melting point is just below human body temperature.

Blue cheese

Blue cheese or bleu cheese is cheese made with cultures of the mold Penicillium, giving it spots or veins of the mold throughout the cheese, which can vary in color through various shades of blue and green. This carries a distinct smell, either from that or various specially cultivated bacteria. Some blue cheeses are injected with spores before the curds form, and others have spores mixed in with the curds after they form. Blue cheeses are typically aged in a temperature-controlled environment such as a cave. Blue cheese can be eaten by itself or can be spread, crumbled or melted into or over a range of other foods. Blue cheese is known for its pungent creamy texture.

Coenraad Johannes van Houten Dutch businessman

Coenraad Johannes van Houten was a Dutch chemist and chocolate maker known for the treatment of cocoa mass with alkaline salts to remove the bitter taste and make cocoa solids more water-soluble; the resulting product is still called "Dutch process chocolate". He is also credited with introducing a method for pressing the fat from roasted cocoa beans, though this was in fact his father, Casparus van Houten's invention.

Churning (butter)

Churning is the process of shaking up cream or whole milk to make butter, usually using a butter churn. In Europe from the Middle Ages until the Industrial Revolution, a churn was usually as simple as a barrel with a plunger in it, moved by hand. These have mostly been replaced by mechanical churns.

Big Turk is a candy bar manufactured by Nestlé Canada, that consists of dark magenta Turkish delight coated in a chocolate coating.

Polyglycerol polyricinoleate

Polyglycerol polyricinoleate (PGPR), E476, is an emulsifier made from glycerol and fatty acids. In chocolate, compound chocolate and similar coatings, PGPR is mainly used with another substance like lecithin to reduce viscosity. It is used at low levels, and works by decreasing the friction between the solid particles in molten chocolate, reducing the yield stress so that it flows more easily, approaching the behaviour of a Newtonian fluid. It can also be used as an emulsifier in spreads and in salad dressings, or to improve the texture of baked goods. It is made up of a short chain of glycerol molecules connected by ether bonds, with ricinoleic acid side chains connected by ester bonds.

Types of chocolate A range of foods derived from cocoa

Chocolate is a range of foods derived from cocoa (cacao), mixed with fat and finely powdered sugar to produce a solid confectionery. There are several types of chocolate, classified according to the proportion of cocoa used in a particular formulation.

Hershey Kissables were a chocolate candy sold by The Hershey Company from late 2005 to 2009. Comparable to M&M's, Hershey Kissables were shaped like miniature Hershey's Kisses and were coated in a thick sugar shell.

Hersheys Cookies n Creme American/Canadian candy bar

Hershey's Cookies 'n' Creme is a candy bar manufactured by The Hershey Company.

Chocolate bloom

Chocolate bloom is either of two types of whitish coating that can appear on the surface of chocolate: fat bloom, caused by changes in the fat crystals in the chocolate; and sugar bloom, due to crystals formed by the action of moisture on the sugar. Fat and sugar bloom damage the appearance of chocolate and limit its shelf life. Chocolate that has "bloomed" is still safe to eat, but may have an unappetizing appearance and surface texture. Chocolate bloom can be repaired by melting the chocolate down, stirring it, then pouring it into a mold and allowing it to cool, bringing the sugar or fat back into the solution.

The following outline is provided as an overview of and topical guide to chocolate:

Sour cream

Sour cream or soured cream is a dairy product obtained by fermenting regular cream with certain kinds of lactic acid bacteria. The bacterial culture, which is introduced either deliberately or naturally, sours and thickens the cream. Its name comes from the production of lactic acid by bacterial fermentation, which is called souring. Crème fraîche is one type of sour cream with a high fat content and less sour taste.

Pasta processing production of pasta

Pasta processing is the process in which wheat semolina or flour is mixed with water and the dough is extruded to a specific shape, dried and packaged.

References

  1. 1 2 Emmanuel Ohene Afoakwa, Chocolate Science and Technology, John Wiley and Sons, 2010, ISBN   1-4051-9906-7, pages 43, 65–66.
  2. McClements, D. Julian Understanding and Controlling the Microstructure of Complex Foods, Woodhead Publishing, 2007, ISBN   978-1-4200-6573-2, page 654.
  3. "The Lindt Invention". chocolate.lindt.com. Lindt & Sprüngli. Retrieved 25 June 2020.
  4. 1 2 3 Talbot, Geoff (ed), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products, Woodhead Publishing, 2009, ISBN   978-1-84569-390-9, chapter 2.5 Conching.
  5. 1 2 Ranken, M. D.; Kill, R. C.; Baker, C. G. J. (ed.), Food Industries Manual (24th Edition), Springer-Verlag, 1997, ISBN   978-0-7514-0404-3, pages 438–439.