Honey

Antimicrobial Properties

Honey has the capacity to serve as a natural food preservative. Research has demonstrated the potential for honey to reduce enzymatic browning in fruits and vegetables and prevent lipid oxidation in meats. Most of the antibacterial activity of the honeys occurs due to hydrogen peroxide generation.1 Other researchers have identified the flavonoids in honey, particularly caffeicacid and ferulicacid, as the most likely contributors.

Antioxidants

Honey contains a variety of phytochemicals (as well as other substances such as organic acids, vitamins, and enzymes) that may serve as sources of dietary antioxidants (Gheldof and Engeseth 2002; Gheldof et al. 2002). The amount and type of these antioxidant compounds depends largely upon the floral source/ variety of the honey (Gheldof et al. 2002). In general, darker honeys have been shown to be higher in antioxidant content than lighter honeys (Gheldof et al. 2002). Researchers at the University of Illinois Champaign/Urbana examined the antioxidant content (using an assessment technique known as Oxygen Radical Absorbance Capacity or ORAC) of 14 unifl oral honeys compared to a sugar analogue. ORAC values for the honeys ranged from 3.0 μmol TE/g for acacia honey to 17.0 μmol TE/g for Illinois buckwheat honey. The sugar analogue displayed no antioxidant activity.

Antioxidant Activity (Measured by Oxygen Radical Absorbance Capacity or ORAC) and Total Phenolic Content of Honeys from Various Sources Compared to a Sugar Analogue* + (mean ± SD)

+ Data from: Gheldof N and Engeseth NJ. Antioxidant capacity of honeys from various floral sources based on the determination of oxygen radical absorbance capacity and inhibition of in vitro lipoprotein oxidation in human serum samples. J Agric Food Chem. 2002;50:3050-3055. aORAC values of all honeys were significantly greater than that for the sugar analogue.

Calories

Honey is a natural source of readily available carbohydrates providing 64 calories per tablespoon

Chemical Characteristics

pH

Honey contains a number of acids which include amino acids (0.05-0.1%) and organic acids (0.57%, range: 0.17-1.17%). The average pH of honey is 3.9 (with a typical range of 3.4 to 6.1).

Proteins, Amino Acids & Isoelectric Point
Protein 0.266%
Nitrogen 0.043%
Amino Acids 0.05 – 0.1%
Isoelectric Point 4.3

Color

Honey is classified by the U.S. Department of Agriculture into seven color categories: water white, extra white, white, extra light amber, light amber, amber and dark amber.

Composition

Honey is composed primarily of the sugars glucose and fructose; its third greatest component is water. Honey also contains numerous other types of sugars, as well as acids, proteins and minerals.4,5 Carbohydrates are described by the number of sub-units they contain. Fructose and glucose are monosaccharides, that is, simple sugars. Sucrose, which is composed of fructose and glucose linked together, is a disaccharide; it comprises a little over 1 percent of the composition of honey. Honey contains other disaccharides which make up over 7 percent of its composition. Some of the disaccharides in honey are maltose, sucrose, kojibiose, turanose, isomaltose, and maltulose. In addition, honey also contains carbohydrates known as oligosaccharides. These are medium- sized carbohydrates, containing more than three simple sugar sub-units, often made of mono- and disaccharides.

Crystallization

Honey sometimes takes on a semi-solid state known as crystallized or granulated honey. This natural phenomenon happens when glucose, one of three main sugars in honey, spontaneously precipitates out of the supersaturated
honey solution. Honey crystallizes because it is a supersaturated solution. This supersaturated state occurs because there is so much sugar in honey (more than 70%) relative to the water content (often less than 20%). Glucose tends to precipitate out of solution and the solution changes to the more stable saturated state

Diabetes

In the past, people with diabetes were advised to avoid “simple sugars” including honey. It was thought that consuming simple sugars would cause a sharp and rapid elevation in blood glucose levels and an overwhelming insulin demand. Some even speculated that eating simple sugars could cause diabetes, a notion that has not been supported by scientific research. In fact, research has shown that some complex carbohydrates raise blood glucose levels more significantly than certain simple sugars (see Glycemic Index). Both honey and sucrose have been shown to produce a lower glucose response than starchy foods such as white bread. Moreover, it has been shown that the total amount of carbohydrate consumed is probably more important than the type of carbohydrate when it comes to blood sugar levels. Thus, experts agree that diabetics may include moderate amounts of “simple sugars” in a balanced diet.6

Dried Honey

Dried honey products available commercially for industrial use are derived from pure liquid honey (1) to which have been added processing aids and other ingredients, (2) which has been dried to a low moisture content, and (3) which in most cases has been converted to a free-flowing product. Processing aids and other ingredients are added to keep the dried honey free-flowing and to modify and enhance the functionality of the product.

Enzymes

Honey naturally contains small amounts of enzymes that are introduced into honey by the bees during various phases of the honey manufacturing process. The predominant enzymes in honey are diastase (amylase), invertase (α-glucosi-dase) and glucose oxidase. Other enzymes such as catalase and acid phosphatase, are generally present in lesser amounts. While enzyme type is fairly uniform across honey varieties the amount of enzyme present can vary widely7. Enzymes play an important role in honey and contribute to its functional

properties.

Fermentation

Fermentation in honey is caused by osmophilic yeasts. It will not occur in honey that has a carbohydrate content > 83%, a moisture content < 17.1%, a storage temperature < 52° F (11° C), or that has been heat-treated. Properly extracted, treated and stored honey should not ferment.

Flavor Enhancement

The carbohydrates found in honey have the ability to improve the intensity of desirable flavors and reduce the intensity of others. Honey enhances sweetness intensity, decreases sourness, decreases the bitterness intensity and increases the acceptability of savory products by modifying saltiness perception.

Floral Sources

There are over 300 floral sources for honey in the United States, including clover, alfalfa, buckwheat and orange blossom. Honey’s color and flavor vary with its floral source.

Freezing Point Depression

15% honey solution: 29.44 to 29.25 °F (-1.42 to -1.53 °C). A 68% honey solution freezes at 21.6 °F (-5.78 °C).

Glycemic Index

Glycemic Index (GI) is defined as the incremental area under the blood glucose response curve of a 50 g portion of a test food expressed as a percentage of the response to the same amount of a reference food (generally white bread or glucose). In other words, the GI describes the rate and extent to which 50 grams of a carbohydrate-rich food will raise blood glucose levels. It has been hypothesized that floral variety can impact the GI of honey dew, at least in part, to differences in the simple sugar concentrations (particularly the fructose : glucose ratio). According to the most recently published International Table of Glycemic Index Values (Foster-Powell et al. 2002), the GIs for honeys from different floral varieties and origins (including Australia, Canada, and Romania) ranges from 35-87. Researchers at San Diego State University recently examined the GI of four US honeys varying in fructose : glucose ratio (Ischayek et al. 2005). The average GI value for the honeys was 72.6 and there were no significant differences between the four honey varieties indicating that small differences in fructose: glucose ratio do not impact the GI of honey.