With Valentine’s Day upon us, we thought we’d share some thoughts on most everybody’s favorite confection – chocolate! While it’s true that many more confectionaries can and are made using continuous processors, we think chocolate deserves its very own forum. We will discuss a bit of the process science involved; some health facts, and finally a little history just for some fun.
Below in italics are some excerpts on chocolate from an article on chocolate conching as seen in Food Processing Magazine.
The powder used to begin conching derives from a set process in which cocoa beans are roasted, crushed, blended and then ground. During grinding, the “nib” – or meat – of the bean liquefies into a paste known as cocoa liquor, which contains cocoa butter, a natural fat, and the dry matter of the bean. The cocoa liquor is then mixed with sugar (and milk for milk chocolate) and refined to a powder.
In simple terms, conching transforms chocolate mass from a powdery aggregate to a fluid. “Traditionally, it’s been associated with low-shear operations of long duration, though shear rates have increased over the years to shorten the process” (Ziegler 2003).
First, let’s define what low-shear operations are. Low-shear operations in regard to conching refer to the slow process wherein some sort of mixing and/or rolling device kneads a ground chocolate paste until the desired flavor, texture, and consistency is achieved. This process in a non-continuous machine takes anywhere from several hours to several days – depending on the desired quality. Continuous processing outputs can achieve the same results for high-quality chocolate in a matter of minutes.
Few confections are as shrouded in myth, mystery and misunderstanding as chocolate. It’s sinfully delicious, to be sure, but is chocolate really as guilty a pleasure as it’s purported to be? Apparently not, in recent years, science has done much to melt some of the myths surrounding chocolate and health.
Take the assumption that chocolate raises cholesterol. Although saturated fats typically increase cholesterol in our bodies, stearic acid, the main saturated fat in chocolate, does not raise blood cholesterol levels. In fact, studies suggest that chocolate not only doesn’t raise low-density lipoprotein levels (LDL or “bad cholesterol”), but actually increases high-density lipoprotein levels (HDL or “good cholesterol”).
To the added advantage of chocolate’s health benefits is the fact that the Continuous Processor is a closed system which utilizes USDA sanitary standards. Batch mixing on the other hand is an open system with multiple opportunities for foreign materials to enter into the process stream.
Chocolate was originally enjoyed in liquid form by first the Aztecs and Mayans of the per-Columbian America’s, and then by the Spanish, English and French during the age of exploration. It wasn’t until mid-1800 that chocolate was made for eating, and another 25 years until milk was added to balance the bitterness of the bean.
Another milestone in chocolate’s sweet history is that Readco processors have been continuously churning it out for over 40 years!
Gregerson, J. The low – or is it high? – shear of a process known as conching helps enhance the flavor and texture of chocolate. Or does it? Food Processing Magazine. (2003)