Cocoa Processing

After cocoa beans have been received at the processing location, they are inspected and thoroughly cleaned of all extraneous matter, such as sticks, stones, and metal fragments, as well as broken beans. The cleaning process involves blowers, which remove items that are lighter or heavier than cocoa beans, and sieves which eliminate items that are too small or too big.

Once the beans are cleaned, the processor has the option of roasting them before the shell is removed, or of removing the shell before roasting. The inside of the cocoa bean is called the nib. Generally speaking, chocolate manufacturers prefer to roast the beans before shelling them, while cocoa processors favor the nib-roasting process.

Bean roasting allows for more variety in the degree of roast and development of flavor, but requires beans of a uniform size, while nib roasting is more even and does not require uniform bean size. Removing the shell before roasting prevents migration of cocoa butter from the bean into the shell during the roasting process.

Once the beans have been shelled and roasted (or roasted and shelled, as the case may be), the nib is ground into a paste. The heat generated by this process causes the cocoa butter in the nib to melt, hence the name ‘cocoa liquor’. It is also known as cocoa paste, chocolate paste, cocoa mass or in the United States Food Standards of Identify, simply as chocolate. Once further refined, it also is called unsweetened baking chocolate.

Chocolate liquor destined for processing into cocoa butter and cake is refined to a very small particle size, as it is easier to reduce the particle size earlier, when the butter is still present, rather than later, when most of the butter has been pressed out. A smaller particle size makes butter extraction easier.

Chocolate liquor destined for chocolate production need not be as finely ground. Indeed, a larger particle size is preferable because it requires less cocoa butter than finely ground liquor to give the same mouth feel to the finished chocolate. This is an important economic consideration.

In the cocoa-processing operation, the liquor is now fed into hydraulic presses that remove a predetermined percentage of the cocoa butter, leaving behind a cake which, according to the processor’s requirements, may contain anything from 6% to 24% of cocoa butter. The cocoa butter so extracted is then filtered and stored in tanks in liquid form until ready to be turned over to the chocolate operation, if at the same location. Otherwise it is shipped to its final destination either in liquid form in tank trucks or in mounded form in cartons. It is sold as ‘pure, prime pressed, natural’ cocoa butter, usually considered to be best quality.

The cocoa cake is either broken into smaller pieces (kibbled) and sold into the generic cocoa cake market, or it is ground into a fine powder.

The cocoa processor has the option of treating the nib or the liquor with an alkali solution (alkalizing), which will reduce the acidity by increasing the normal pH factor from about 5.0 up to 8.0. This treatment is also known as ‘dutching’. It was invented in the late 1800s by the Dutchman C. J. Van Houten, who developed the cocoa butter pressing operation as well.

Alkalizing cocoa nib or cocoa liquor renders the powder darker, gives it a milder, but more chocolaty flavor, and allows it to stay in suspension longer in liquids such as milk. It generally commands a premium over natural cocoa powder.

On the other hand, the cocoa butter extracted from alkalized liquor does have a more pungent and less desirable odor and flavor, and must be deodorized, as well as refined. It is then carefully blended with other cocoa butters, so that the resulting final butter for sale is consistent in its bland flavor, color and viscosity.

Virtually all the cocoa butter produced by the international cocoa processing industry is used in the manufacture of chocolate, where it must be added to the liquor to achieve the desired result. The pharmaceutical and cosmetics industries, which also use cocoa butter, may obtain their requirements from sources using solvent extraction or methods other than pressing cocoa butter from cocoa shell. Some may use cocoa beans that are not suitable as a food item.

Source: www.chocolateandcocoa.org