By J. W. WHITE, JR. AND LANDIS W. DONER
Research leader and research chemist, respectively, Science and Education Administration, Eastern Regional Research Center, Philadelphia, Pa. 19118.
BEEKEEPING IN THE UNITED STATES
AGRICULTURE HANDBOOK NUMBER 335
Revised October 1980
Pages 82 - 91
Honey is essentially a highly concentrated water solution of two sugars, dextrose and levulose, with small amounts of at least 22 other more complex sugars. Many other substances also occur in honey, but the sugars are by far the major components. The principal physical characteristics and behavior of honey are due to its sugars, but the minor constituents - such as flavoring materials, pigments, acids, and minerals - are largely responsible for the differences among individual honey types.
Honey, as it is found in the hive, is a truly remarkable material, elaborated by bees with floral nectar, and less often with honeydew. Nectar is a thin, easily spoiled sweet liquid that is changed ("ripened") by the honey bee to a stable, high-density, high-energy food. The earlier U.S. Food and Drug Act defined honey as "the nectar and saccharine exudation of plants, gathered, modified, and stored in the comb by honey bees (Apis mellifera and A. dorsata); is levorotatory; contains not more than 25% water, not more than 0.25% ash, and not more than 8% sucrose." The limits established in this definition were largely based on a survey published in 1908. Today, this definition has an advisory status only, but is not totally correct, as it allows too high a content of water and sucrose, is too low in ash, and makes no mention of honeydew.
Colors of honey form a continuous range from very pale yellow through ambers to a darkish red amber to nearly black. The variations are almost entirely due to the plant source of the honey, although climate may modify the color somewhat through the darkening action of heat.
The flavor and aroma of honey vary even more than the color. Although there seems to be a characteristic "honey flavor," almost an infinite number of aroma and flavor variations can exist. As with color, the variations appear to be governed by the floral source. In general, light-colored honey is mild in flavor and a darker honey has a more pronounced flavor. Exceptions to the rule sometimes endow a light honey with very definite specific flavors. Since flavor and aroma judgments are personal, individual preference will vary, but with the tremendous variety available, everyone should be able to find a favorite honey.
Composition of Honey
By far, the largest portion of the dry matter in honey consists of the sugars. This very concentrated solution of several sugars results in the characteristic physical properties of honey - high viscosity, "stickiness," high density, granulation tendencies, tendency to absorb moisture from the air, and immunity from some types of spoilage. Because of its unique character and its considerable difference from other sweeteners, chemists have long been interested in its composition and food technologists sometimes have been frustrated in attempts to include honey in prepared food formulas or products. Limitations of methods available to earlier researchers made their results only approximate in regard to the true sugar composition of honey. Although recent research has greatly improved analytical procedures for sugars, even now some compromises are required to make possible accurate analysis of large numbers of honey samples for sugars.
An analytical survey of U.S. honey is reported in Composition of American Honeys, Technical Bulletin 1261, published by the U.S. Department of Agriculture in 1962. In this survey, considerable effort was made to obtain honey samples from all over the United States and to include enough samples of the commercially significant floral types that the results, averaged by floral type, would be useful to the beekeeper and packer and also to the food technologist. In addition to providing tables of composition of U.S. honeys, some general conclusions were reached in the bulletin on various factors affected by honey composition.
Where comparisons were made of the composition of the same types of honey from 2 crop years, relatively small or no differences were found. The same was true for the same type of honey from various locations. As previously known, dark honey is higher than light honey in ash (mineral) and nitrogen content. Averaging results by regions showed that eastern and southern honeys were darker than average, whereas north-central and intermountain honeys were lighter. The north-central honey was higher than average in moisture, and the intermountain honey was more heavy bodied. Honey from the South Atlantic States showed the least tendency to granulate, whereas the intermountain honey had the greatest tendency.
The technical bulletin includes complete analyses of 490 samples of U.S. floral honey and 14 samples of honeydew honey gathered from 47 of the 50 States and representing 82 "single" floral types and 93 blends of "known" composition. For the more common honey types, many samples were available and averages were calculated by computer for many floral types and plant families. Also given in this bulletin are the average honey composition for each State and region and detailed discussions of the effects of crop year, storage, area of production, granulation, and color on composition. Some of the tabular data are included in this handbook.
Table 1 gives the average value for all of the constituents analyzed in the survey and also lists the range of values for each constitutent. The range shows the great variability for all honey constituents. Most of the constituents listed are familiar. Levulose and dextrose are the simple sugars making up most of the honey. Fructose and glucose are other commonly used names for these sugars. Sucrose (table sugar) also is present in honey, and is one of the main sugars in nectar, along with levulose and dextrose. "Maltose" is actually a mixture of several complex sugars, which are analyzed collectively and reported as maltose. Higher sugars is a more descriptive term for the material formerly called honey dextrin.
The undetermined value is found by adding all the sugar percentages to the moisture value and subtracting from 100. The active acidity of a material is expressed as pH; the larger the number the lower is the active acidity. The lactone is a newly found component of honey. Lactones may be considered to be a reserve acidity, since by chemically adding water to them (hydrolysis) an acid is formed. The ash is, of course, the material remaining after the honey is burned and represents mineral matter. The nitrogen is a measure of the protein material, including the enzymes, and diastase is a specific starch-digesting enzyme.
Most of these constituents are expressed in percent, that is, parts per hundred of honey. The acidity is reported differently. In earlier times, acidity was reported as percent formic acid. We now know that there are many acids in honey, with formic acid being one of the least important. Since a sugar acid, gluconic acid, has been found to be the principal one in honey, these results could be expressed as "percent gluconic acid" by multiplying the numbers in the table by 0.0196. Since actually there are many acids in honey, the term "milliequivalents per kilogram" is used to avoid implying that only one acid is found in honey. This figure is such that it properly expresses the acidity of a honey sample independently of the kind or kinds of acids present.
In table 1, the differences between floral honey and honeydew honey(2) can be seen. Floral honey is higher in simple sugars (levulose and dextrose), lower in disaccharides and higher sugars (dextrins), and contains much less acid. The higher amount of mineral salts (ash) in honeydew gives it a less active acidity (higher PH). The nitrogen content reflecting the amino acids and protein content is also higher in honeydew.
Research leader and research chemist, respectively, Science and Education Administration, Eastern Regional Research Center, Philadelphia, Pa. 19118.
BEEKEEPING IN THE UNITED STATES
AGRICULTURE HANDBOOK NUMBER 335
Revised October 1980
Pages 82 - 91
Honey is essentially a highly concentrated water solution of two sugars, dextrose and levulose, with small amounts of at least 22 other more complex sugars. Many other substances also occur in honey, but the sugars are by far the major components. The principal physical characteristics and behavior of honey are due to its sugars, but the minor constituents - such as flavoring materials, pigments, acids, and minerals - are largely responsible for the differences among individual honey types.
Honey, as it is found in the hive, is a truly remarkable material, elaborated by bees with floral nectar, and less often with honeydew. Nectar is a thin, easily spoiled sweet liquid that is changed ("ripened") by the honey bee to a stable, high-density, high-energy food. The earlier U.S. Food and Drug Act defined honey as "the nectar and saccharine exudation of plants, gathered, modified, and stored in the comb by honey bees (Apis mellifera and A. dorsata); is levorotatory; contains not more than 25% water, not more than 0.25% ash, and not more than 8% sucrose." The limits established in this definition were largely based on a survey published in 1908. Today, this definition has an advisory status only, but is not totally correct, as it allows too high a content of water and sucrose, is too low in ash, and makes no mention of honeydew.
Colors of honey form a continuous range from very pale yellow through ambers to a darkish red amber to nearly black. The variations are almost entirely due to the plant source of the honey, although climate may modify the color somewhat through the darkening action of heat.
The flavor and aroma of honey vary even more than the color. Although there seems to be a characteristic "honey flavor," almost an infinite number of aroma and flavor variations can exist. As with color, the variations appear to be governed by the floral source. In general, light-colored honey is mild in flavor and a darker honey has a more pronounced flavor. Exceptions to the rule sometimes endow a light honey with very definite specific flavors. Since flavor and aroma judgments are personal, individual preference will vary, but with the tremendous variety available, everyone should be able to find a favorite honey.
Composition of Honey
By far, the largest portion of the dry matter in honey consists of the sugars. This very concentrated solution of several sugars results in the characteristic physical properties of honey - high viscosity, "stickiness," high density, granulation tendencies, tendency to absorb moisture from the air, and immunity from some types of spoilage. Because of its unique character and its considerable difference from other sweeteners, chemists have long been interested in its composition and food technologists sometimes have been frustrated in attempts to include honey in prepared food formulas or products. Limitations of methods available to earlier researchers made their results only approximate in regard to the true sugar composition of honey. Although recent research has greatly improved analytical procedures for sugars, even now some compromises are required to make possible accurate analysis of large numbers of honey samples for sugars.
An analytical survey of U.S. honey is reported in Composition of American Honeys, Technical Bulletin 1261, published by the U.S. Department of Agriculture in 1962. In this survey, considerable effort was made to obtain honey samples from all over the United States and to include enough samples of the commercially significant floral types that the results, averaged by floral type, would be useful to the beekeeper and packer and also to the food technologist. In addition to providing tables of composition of U.S. honeys, some general conclusions were reached in the bulletin on various factors affected by honey composition.
Where comparisons were made of the composition of the same types of honey from 2 crop years, relatively small or no differences were found. The same was true for the same type of honey from various locations. As previously known, dark honey is higher than light honey in ash (mineral) and nitrogen content. Averaging results by regions showed that eastern and southern honeys were darker than average, whereas north-central and intermountain honeys were lighter. The north-central honey was higher than average in moisture, and the intermountain honey was more heavy bodied. Honey from the South Atlantic States showed the least tendency to granulate, whereas the intermountain honey had the greatest tendency.
The technical bulletin includes complete analyses of 490 samples of U.S. floral honey and 14 samples of honeydew honey gathered from 47 of the 50 States and representing 82 "single" floral types and 93 blends of "known" composition. For the more common honey types, many samples were available and averages were calculated by computer for many floral types and plant families. Also given in this bulletin are the average honey composition for each State and region and detailed discussions of the effects of crop year, storage, area of production, granulation, and color on composition. Some of the tabular data are included in this handbook.
Table 1 gives the average value for all of the constituents analyzed in the survey and also lists the range of values for each constitutent. The range shows the great variability for all honey constituents. Most of the constituents listed are familiar. Levulose and dextrose are the simple sugars making up most of the honey. Fructose and glucose are other commonly used names for these sugars. Sucrose (table sugar) also is present in honey, and is one of the main sugars in nectar, along with levulose and dextrose. "Maltose" is actually a mixture of several complex sugars, which are analyzed collectively and reported as maltose. Higher sugars is a more descriptive term for the material formerly called honey dextrin.
The undetermined value is found by adding all the sugar percentages to the moisture value and subtracting from 100. The active acidity of a material is expressed as pH; the larger the number the lower is the active acidity. The lactone is a newly found component of honey. Lactones may be considered to be a reserve acidity, since by chemically adding water to them (hydrolysis) an acid is formed. The ash is, of course, the material remaining after the honey is burned and represents mineral matter. The nitrogen is a measure of the protein material, including the enzymes, and diastase is a specific starch-digesting enzyme.
Most of these constituents are expressed in percent, that is, parts per hundred of honey. The acidity is reported differently. In earlier times, acidity was reported as percent formic acid. We now know that there are many acids in honey, with formic acid being one of the least important. Since a sugar acid, gluconic acid, has been found to be the principal one in honey, these results could be expressed as "percent gluconic acid" by multiplying the numbers in the table by 0.0196. Since actually there are many acids in honey, the term "milliequivalents per kilogram" is used to avoid implying that only one acid is found in honey. This figure is such that it properly expresses the acidity of a honey sample independently of the kind or kinds of acids present.
In table 1, the differences between floral honey and honeydew honey(2) can be seen. Floral honey is higher in simple sugars (levulose and dextrose), lower in disaccharides and higher sugars (dextrins), and contains much less acid. The higher amount of mineral salts (ash) in honeydew gives it a less active acidity (higher PH). The nitrogen content reflecting the amino acids and protein content is also higher in honeydew.
TABLE 1.-Average composition of floral and honeydew honey and range of values(1) |