Use and Handling of Chocolate

General Guidelines

While detailed knowledge of chocolate manufacturing is not essential for confectionery success, knowing how to handle and store chocolate is. The basic guidelines for handling chocolate are rather simple: Always keep chocolate away from moisture and excessive heat; these are the two factors that destroy chocolate more rapidly than all others. Also, chocolate should be stored in a cool, dark place, away from strong odors that can taint its flavor.

A very small amount of moisture in chocolate will noticeably increase its viscosity, making it unacceptable for dipping or enrobing. When melting chocolate, be careful not to allow excess steam to develop, which will interface with the surface of the chocolate, moistening it and increasing the viscosity. When working with chocolate, always be certain that all utensils and surfaces are dry. Chocolate that has been exposed to moisture may still be used in some applications, such as chocolate caramels or chocolate fudge, but should not be used for dipping or enrobing.

Excessive heat will cause chocolate to form grains and to thicken. Dark chocolate should not be heated over 50 Celsius. Milk and white chocolate are especially vulnerable to damage from heat, due to the milk solids they contain; to prevent damage, do not heat them over 40 Celsius. When melting small quantities of chocolate, it is important to chop it finely, melt it over a warm, and stir it as it melts. The chocolate must be chopped in order to ensure that it melts evenly and quickly without overheating. The water bath should be warm, not boiling. a boiling water bath will not only introduce the hazard of steam, but will also overheat the chocolate in the bottom of the bowl, stirring ensures that the chocolate will melt evenly without overheating. An alternative method for melting chocolate is the very gentle dry heat of a melter. These devices can be set for the desired temperature, and the chocolate left overnight to melt, without having to be chopped beforehand or stirred while melting, making the melters the easiest way to melt larger quantities of chocolate.

Work Environment

All work with chocolate should be carried out in a temperature-controlled, low-humidity environment. Although various steps of confectionery production may be best accomplished at different temperatures, most artisan confectioners do not have the luxury of having more than one temperature-controlled room for chocolate work. For general chocolate work, including crystallization of the finished pieces, an ambient temperature of 20 Celsius is appropriate with a humidity level of 45 to 50 percent. Temperature significantly higher than this will cause the chocolate to crystallize too slowly. Temperatures that are much lower will result in rapid cooling and an increase of viscosity, as well as the formation of unstable cocoa butter crystals, causing poor gloss and snap, and the formation of bloom during storage.

In Thailand the humidity level is varying from 60% to 90% depending of the season, which is too high for working with chocolate. To bring the humidity level down to 45-50 % it is recommended to purchase a dehumidifier.

Chocolate storage Guidelines

Because chocolate contains virtually no moisture, it has very low water activity level, and is not prone to bacterial spoilage during storage, resulting in a long shelf life. The factor limiting shelf life for chocolate is rancidity, the breakdown of fats than can create off flavors. Although cocoa butter is relatively resistant to rancidity, chocolate should be stored protected from exposure to oxygen, light, heat, and moisture (humidity), and when working with chocolate, do not expose it to reactive metals such as copper and iron. All these factors shorten the potential shelf life by increasing the likelihood of the onset of rancidity. When stored under ideal conditions, dark chocolates have a shelf life of approximately 12 months, while milk and white chocolates have a shelf life of approximately 6 months. These are the maximum times suggested for storing chocolate. The artisan confectioner is well advised to turn over his chocolate inventory much more rapidly to ensure the highest-quality products with the freshest flavor.

Bloom

 In confectionery, bloom refers to the gray cast, streaks, or spots that appear on poorly handled chocolate. There are two different types of bloom: fat bloom and sugar bloom. Fat bloom is the visible crystallization of fat on the surface of chocolate. It is caused by improperly tempered or stored chocolate.

Chocolate that has been allowed to set without proper tempering will immediately form fat bloom. Chocolate that has been pre-crystallized with the wrong form of crystals will form fat bloom during storage. If during storage, the chocolate melts and then re-crystallizes, it will also exhibit fat bloom.

Sugar bloom is the formation of sugar crystals on the surface of chocolate. It is caused by the exposure of chocolate to high humidity or other moisture. When exposed to moisture, the sugar particles on the surface of the chocolate absorb the moisture, and dissolve. When the moisture subsequently evaporates, the sugar re-crystallizes, in larger crystals, resulting in sugar bloom.

It is difficult to distinguish sugar bloom from fat bloom by sight alone, but there is a simple test to determine the source of the bloom: gently rub a sample of the bloomed chocolate on your lip or wrist. If the chocolate feels smooth, the bloom is fat bloom. If there is a noticeable rough texture to the chocolate, it is sugar bloom.