WHAT'S THAT STUFF?
honey Bees rely on enzymes to create the WORLD'S FIRST ready-to-eat sweetener FLOWERS, BEES, and biochemistry: these are three of the essentials for making floral honey—one of my favorite foods. Bees produce and store honey as a food source. The final product is made of roughly 80% sugar, 17% water, and a hodgepodge of trace compounds that are critical to the honey's varied flavors and colors. The most abundant sugars in honey are fructose and _glucose. Among the myriad minor complex sugars in the goo are maltose, sucrose, and other disaccharides, as v/ell as trisaccharides such as erlose. To make this delicious treat, foraging bees start out by guzzling nectar, a dilute solution of sugars in flowers. Then, they mix the nectar with enzymes in their stomachlike honey sacs. Back at the hive, the foragers pass the digested material to house bees who reduce the moisture content of the mixture by ingesting and regurgitating it. They then deposit concentrated drops into honeycomb cells. Over the next few days, bees fan the fluid with their wings to further concentrate it, and finally, they cap the cells with wax. At the same time, enzyme-mediated changes produce a range of sugars and acids in the honey. Bee enzymes also show up in the finished product. Invertase is the most critical. It splits the sucrose in the nectar into fructose and glucose and also produces some erlose. Another enzyme, glucose oxidase, converts glucose to gluconolactone, which is then hydrolyzed to give gluconic acid, the principal acid in honey. Formic, acetic, butyric, and lactic acids are also found in honey, which explains why its pH typically measures 3.8-4.0 and bacteria have a hard time growing in it. Honey also contains small amounts of minerals and proteins.
to price in the honey one-third of the ash. HONEY business. Light honeys Other trace elements AT A GLANCE sold by the bottle have in honey include iron, manganese, a more popular flavor China is the largest producer of honcopper, and silicon. and are more expeney, churning out about 700 million lb each year. The U.S. is the largest sive than strongly flaThe sweetener also honey consumer, using about 300 vored, darker honeys contains up to 1% nimillion lb per year. used in industry as trogen, which comes food ingredients. principally from proA bee makes less than one-twelfth of teins. These proteins Honey's cachet as a teaspoon of honey in its lifetime. an ingredient in food can cause honey to Erlose was discovered at and named products has fueled foam and form tiny after the USDA Eastern Regional Rean increased demand air bubbles. search Center, in Pennsylvania, where worldwide, says Jerry Of the more than it was first isolated from honey. Probst, a consultant 100 compounds for the National found in honey, many Honey Board and a former president of are volatile organic compounds, such as the Sioux Honey Association. As a result, phenylethyl alcohol, that contribute to flahoney fraud exists. In fact, "much of what vor. "The honey flavor is dependent on the has been learned about the composition flavor compounds and aroma compounds and properties of honey has resulted from that come from a flower," explains William research aimed at verifying its authenticF. Huser, vice president of Sioux City, Iowaity," according to Landis W. Doner, one based Sioux Honey Association, which has of the investigators in a pioneering honey 300 beekeeper members in North America research program during the 1960s to '80s and markets U.S. clover honey under the at the Department of Agriculture's Eastern SueBee brand. Regional Research Center, in Pennsylvania. Because weather and geography affect Analytical techniques, including liquid flowers, Huser notes, each batch of, say, chromatography, thin-layer chromatograclover honey can have a slightly different phy, and mass spectrometric stable carbon makeup of flavor chemicals. And clover isotope ratio analysis, can help assess honey has a distinctly different flavor whether honey has been adulterated with than, for instance, orange honey found in corn syrup or cane or beet sugars. Doner California and Florida or cranberry honey and associates at USDA created many of found in New England. the first methods to analyze honey with these techniques. At certain levels, howIF NECTARS from a single flower species ever, these additives are virtually undetectvary from plant to plant, region to region, able because all of their major components and season to season, how does a brand also occur naturally in honey. maintain a uniform taste? Processors usually mix different batches of the same Huser adds that U.S. researchers comvariety of floral honey. "We are constantly monly test for both legal and illegal residoing a blend to get the proper moisture, dues. They rely on gas chromatography to the proper color, and the proper flavor," test for pesticides in honey, and they turn to Huser explains. For example, he notes, enzyme-linked immunosorbent assays to "We'll blend clover honeys from Montana, detect antibiotics. He notes that adulterawhich have one set of characteristics, with tion can also result from the removal of key clover honeys from Minnesota, which have components from honey. For example, proa different set of characteristics." cessors that use ultrafiltration to remove problematic residues may inadvertently To grade the color of honey, many in the extract some of honey's higher sugars and industry still use traditional colorimetric possibly even all of its flavor compounds. analysis, which relies on matching color by sight. Nowadays, however, many processors And without the flavor, honey essentialrate color by using various electronic cololy becomes just another sugary syrup.— rimetric analyzers. Color generally equates RACHEL PETKEWICH WWW.CEN-0NLINE.ORG
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