Science / Medicine : The Sweet Truth : Chocolate: Researchers say it doesn’t melt the heart, just in your hands. Those who research the food dispel some myths, but admit that much remains a mystery.
Behind every Hershey’s Kiss, every See’s chocolate heart, and every Lindt’s dark Swiss chocolate bar stand legions of chocolate scientists who have a distinct advantage over those pursuing other types of research--they often eat their experiments.
Whether it is the opportunity for taste-testing that drives women and men to choose chocolate science as a profession is unknown, but the obsession to study the substance has a long history. It emerged in the early 1500s when Spaniards watched the Aztec emperor, Montezuma, drink 50 golden goblets of honey-flavored chocolate a day and took a swig of the sumptuous brew themselves.
That the emperor was said to drink a cup of the frothy liquid before crossing the threshold to his harem did much to promote chocolate’s reputation as an aphrodisiac, a myth that has survived the centuries to make chocolate the premier love offering on Valentine’s Day.
Two men--a Spanish physician and Franciscan friar--who studied Aztec medicine and culture began the official inquiry into cachuatl, the Aztec name for cacao bean, in the mid-1500s. In the 400-plus years since then, scientists have continued the tradition by churning out reams of research on the science and technology of chocolate, much of which entails taste-testing.
Yet, the substance continues to confound them and, thus, offers job prospects to aspiring chocolate scientists.
“We just don’t know enough about it,” said Terry Richardson, veteran of 37 years of chocolate research and president of Richardson Researches Inc., a chocolate and candy consulting company in Hayward, Calif. Richardson eats one or two ounces of chocolate every day. He is not fat.
Among the mysteries: Why does chocolate grown in Ghana taste so different from chocolate grown in Malaysia? What, exactly, makes some chocolate more “intense” than others? How can you increase the intensity in chocolate?
Even the measure of intensity--the “chocolateyness” of chocolate--defies quantitative analysis. Machines cannot do it. Only human taste-testers can.
What scientists do know about chocolate runs from the basic botanical characteristics to the complex--how to size ground-up cocoa particles, a factor in the texture of chocolate, with microscopes and laser beams.
On the basic side, chocolate comes from cacao beans, which grow in large pods off the trunk of a spreading, leafy tropical tree, Theobroma cacao. Theobroma, which means “food of the gods,” originated in the Amazon basin of South America. It thrives only in areas 20 degrees latitude on both sides of the Equator and is cultivated in 35 countries.
When the ripe yellow fruit pods are harvested, the seeds and pulp are removed and fermented to separate the cacao beans from their slimy seed coating. Fermentation is as important as cultivation, said Richardson; beans that are not fermented well do not deliver proper intensity.
The beans are dried, roasted and cracked, the shells and seed germ removed to leave the essence of chocolate: the nib. Nibs are ground into a thick brown goo, known as chocolate liquor, an ingredient often listed on chocolate products. Liquor refers to the “juice” of the chocolate; it is not alcoholic.
This is what Moctezuma II drank, as did the British for years in popular chocolate pubs. The liquor’s high fat content left a froth on the surface of the milk or water with which it was mixed.
In the 1800s, Dutchman C.J. Van Houten developed a method to remove most of the fat and process it into cocoa butter--now used in tanning and beauty aids--leaving dry cocoa that can dissolve more easily in water and milk. Most of today’s commercial cocoa is further processed with alkaline solutions, known as the “Dutch” process, to bring out a rich color.
Technically, chocolate comprises cocoa and sugar. Milk chocolate bars contain cocoa butter, cocoa or chocolate liquor, powdered milk and sugar. Dark chocolate contains no milk or a little milk fat.
Despite its reputation as junk food, chocolate is nutritious. One hundred grams (3.5 ounces) of Hershey’s cocoa provides 27.3 grams of protein, 12.8 grams of fat, 45.7 grams of carbohydrates, 20 milligrams of sodium and significant amounts of calcium, phosphorus, iron, potassium, magnesium, copper, zinc, manganese and Vitamin A. Cocoa, in this case, resembles a baked potato: By itself, it is nutritious. It becomes a dietary nightmare only when cocoa butter, sugar, nuts and saturated fats are added.
A 12-ounce mug of hot chocolate (or Ott Chocolate, made from a recipe of nonfat milk, cocoa and honey provided by Jonathan Ott in his intriguing book “Chocolate Addict”), contains only 17.5 milligrams of caffeine, compared with 100 to 200 milligrams in an equivalent amount of coffee. It is hardly enough to have much effect on most people. Chocolate does contain significant amounts of theobromine, a chemical similar to caffeine.
According to Ott, theobromine does not cause sleeplessness. Some studies have shown that it actually relaxes smooth muscles. In a one-man experiment to test the addictive qualities of theobromine (all in the name of science), Ott consumed heavy doses of chocolate, comparable to the 120- to 300-milligram doses of caffeine required to produce withdrawal symptoms. He reported similar effects of headache, lethargy and muscle tension.
Most chocolate scientists do research on what consumers want most: better chocolate or new chocolate products, such as the bar that was designed for U.S. troops in Saudi Arabia. Since cocoa butter melts at body temperature, fats that melt at higher temperatures are added instead. Chocolate scientists are also concerned with rheology, the flow properties of chocolate that are important in the manufacturing process; the interreactions of different types of milk solids; the crystallization of fats; texture, and how chocolate breaks. The ultimate test, of course, is how it tastes.
Outside candy companies, scientists pursue other aspects of chocolate. At Pennsylvania State University in State College, a in chocolate research, food chemist Paul Dimick, who keeps a jar of chocolate close at hand, works on several projects. They range from determining how chocolate differs among beans grown in various parts of the world, to defining the chemistry of the approximately 400 compounds that give chocolate its flavor, and studying what happens to those compounds during processing.
The American Cocoa Research Institute recently gave the school $1.5 million to focus on cocoa biotechnology, and some researchers have begun mapping the genes of Theobroma, with the aim of improving chocolate quality, increasing seed production and controlling disease.
Rumors and wishful thinking notwithstanding, there is no clear evidence that chocolate is an aphrodisiac, Dimick said. Some people have claimed that because cocoa contains phenylethylamine (PEA), a compound belonging to the family of biologically active amines that affect the involuntary nervous system, it causes a euphoric state similar to the feeling of being in love.
With only five micrograms of PEA per gram (or 200 micrograms in a typical serving of milk chocolate), cocoa does not have enough PEA to affect anything, Dimick said. He cited a study in which 1,600 milligrams of PEA were administered to humans, who showed no signs of euphoria.
Besides, noted Dimick, “fermented cheeses and sausages have 100 times the amount of PEA as cocoa, and nobody is saying that eating cheese will turn you on.”
In California, one of the tasks in which Richardson and his team of five chocolate researchers specializes is identifying the contents of popular chocolate products for competing companies that want to copy them. This entails studying the product microscopically, running a gas chromatograph analysis to pinpoint some of the flavor constituents, and tasting to determine in what country the beans were grown. Then they try to reproduce it. The taste tests are the final proof.
Other chocolate research focuses on shelf life and microbial attack, areas in which UC Davis food technologist George York specializes. Companies send him chocolate bars, chocolate-covered nuts, even chocolate cakes. He described an incident in which he gave his co-workers a box of chocolate truffles from a San Francisco firm he was consulting with. They--and he--were shocked to bite into a moldy, but nonpathogenic, middle. Moisture had collected between two layers of chocolate as they separated during manufacturing and provided a fertile breeding ground for fungi.
York, who is partial to milk chocolate but heretically claims to like pickles just as much, suggested changing the heating process, and the problem disappeared. “You don’t have to worry much about pathogenic bacteria or molds in chocolate,” he said. There’s not much free water available for microbes to grow on in chocolate because it is chemically bound to the sugar and the heating process usually kills any microbes that may ride in on the beans.
In analyzing shelf life, something with which most chocoholics have little experience, York accelerates a chocolate product’s degradation by incubating it at 90 degrees. He removes it periodically to check the texture and color. To check for staleness, he must, naturally, taste it.
Fortunately, chocolate science is not limited to professionals with years of schooling. Enthusiastic amateurs can also dip into the field with Richardson’s five-day course ($1,395) or Dimick’s seven-day course ($1,000) on chocolate technology. Chocoholics take note: Both incorporate hands-on training that requires daily taste-testing.
The basic steps in making chocolate: 1. Workers cut pods from cacao trees. 2. Pods are gathered into heaps and cut open. 3. Beans are scooped out of the pods and are put into a fermentation process that takes 7 to 10 days. The beans are placed in bags. 4. Chocolate manufacturers process the beans with methods including roasting, hulling, blending and grinding, producing seeds without shells called “nibs”. Nibs contain about 54% cocoa butter. 5. The nibs are ground fine, and the cocoa butter is released. the mixture of nibsand cocoa forms a substance called “chocolate liguor.” Chocolate products are all madefrom the chocolate liquor. Source: World Book Encyclopedia
