Effects of Processing on the Pollen and Nutrient Content of Honey
Katherine Beals1, David Ropa2
1University of Utah, Salt Lake City, UT 2Ropa Science Research, Madison, WI.

PURPOSEABSTRACT (#8955)
This pilot study examined the effects of commercial processing
on the pollen and nutrient content of honey. From a total of 22,
55-gallon drums of honey, 5 random drums were chosen toobtain 5 random samples of raw honey (pre-blended raw). The
22 drums were blended and heated at 140 F and 2 additionalrandom samples were selected (blended raw). The blendedhoney settled at 130 F for 12 hours, was manually skimmed(removing foam and extraneous solids), flash heated to 175 F
for 7 minutes, filtered using diatomaceous earth (DE) and flash
cooled to 130 F after which two additional samples were taken(blended (B) filtered). All samples were analyzed by outsidelaboratories (Covance Labs, Madison, WI and ABC Labs,Gainesville, FL) for micronutrient content, antioxidant (AOX)
capacity (ORAC) and pollen content. Processing reduced thepollen content of the honey (P<0.05)*, but did not significantly
affect the nutrient content indicating that the micronutrient profile
of honey is not related to its pollen content and is not significantly
affected by commercial processing.

°°°

To examine the effects of standard commercial processing (i.e.,blending, heating and filtering) on the pollen and nutrient
content as well as the antioxidant capacity of honey.

°

INTRODUCTION
Honey is the substance made when the nectar fromplants is gathered, enzymatically modified and stored in
the honeycomb by honey bees. During the collection ofnectar, bees also pick up some pollen and transfer thatpollen from one flower (which is essential for plantfertilization) as well as carry some of the pollen back to
the hive. However, honey is not produced from pollen; it
is produced from floral nectar.
The color and flavor of honey differ depending on thebees’ predominant nectar source (i.e., the flowerblossoms). It is estimated that there are more than 300
unique kinds of honey in the United States. In general,
lighter colored honeys are mild in flavor, while darker
honeys are usually more robust.
Commercial processing of honey involves heating andfiltering (generally using diatomaceous earth). This helpsdelay crystallization and produce a less cloudy
appearance (preferred by consumers). There is awidespread belief that unprocessed (raw) honey is more
“nutritious” than honey that has been processed, despite
a lack of empirical evidence to support such a belief.

RESULTSDISCUSSION

Table 1This pilot data indicates that processing honey does not
result in the destruction of the key vitamins, minerals andantioxidants found in honey. In fact, processing actually
increased the mineral content and AOX capacity of thehoney. On average, honey’s calcium, magnesium andpotassium levels increased 0.8%, 14.1% and 8.9%,
respectively after processing. Additionally, total
antioxidant capacity increased an average of 8.4%, whilehydrophilic rose 7.6% and lipophilic rose 15%. In
contrast, vitamin content tended to show either nochange or a slight decrease. Folic acid and Vitamin B12experienced no measurable change during heating andfiltration, and pyridoxine dropped 9.6%. As expected,
pollen was completely eliminated after processing.

Micronutrient and Pollen Contents and Antioxidant
Capacity (ORAC) of Pre-Blended (PB) Raw Honey Samples
PB #1

PB #2

PB #3

PB #4

PB #5

3.64

3.94

3.44

3.32

3.37

Pyridoxine (mg)

0.015

0.019

0.02

0.015

0.014

B12 (υg)< 0.012< 0.012< 0.012< 0.012< 0.012--

Folate (υg)<6<6<6<6<6--Pollen (grains/10 g)

76,93357,17853,684

123,11261,42774466.828606.4

ORAC (υmol TE/g)hydrophilic
lipophilic

1.17
1.00
0.168

1.34
1.14
0.195

1.42
1.22
0.199

1.30
1.11
0.185

1.41
1.22
0.188

METHODS

Magnesium (mg)1.4

1.521.31

1.31

1.35

Honey Samples: From a total of 22, 55-gallon drums ofcanola honey (donated by a large honey producer), 5
random drums of the honey were selected to obtain 5
random samples of raw honey (pre-blended (PB) raw). The
22 drums were then blended together and heated to 140 Ffor 18 hours (as is standard process), after which 2
additional samples were selected (blended raw). The entire
batch was then allowed to settle at 130 F for 12 hours after
which the honey was manually skimmed to remove foam
and extraneous solids on the surface of the honey. It wasthen flash heated to 175 F for approximately 7 minutes,
filtered using diatomaceous earth and flashed cooled to130 F after which 2 additional samples were taken(blended processed honey)

Potassium (mg)

13.5

15.1

11.9

11.6

10/8°°°

Measures: All samples were analyzed by outside labs.
Vitamins (vitamin B12, Folate and vitamin B6)1,2, minerals(potassium, magnesium, and calcium)3 and both lipophilic
and hydrophilic antioxidant (AOX) capacity (ORAC)4 wereanalyzed by Covance Labs (Madison, WI). The selection ofvitamins and minerals to be tested on based on the averagequantities found in honey nationwide. Pollen analysis (pollenconcentration in grains per 10 grams of honey) wasconducted by ABC labs (Gainesville, FL).

1Official Methods of Analysis of AOAC INTERNATIONAL, 18th Ed., Methods 952.20

and 960.46, AOAC INTERNATIONAL, Gaithersburg, MD, USA, (2005).
2Folic Acid (FOAN_S:13) Official Methods of Analysis of AOAC INTERNATIONAL,
18th Ed., Methods 960.46 and 992.05
3Elements by ICP Emission Spectrometry (ICP_S:13) Official Methods of Analysis ofAOAC INTERNATIONAL, 18th Ed., Method 984.27 and 985.01, AOAC
INTERNATIONAL, Gaithersburg, MD, USA, (2005)
4ORAC (ORAC_S:4 & ORLP_S:5)) Journal of Agricultural and Food Chemistry(2003)3272-3279.

3.54

±1.33
1.14
0..187± 0.01± 0.91± 0.012

It is worth noting the variability in micronutrient content, AOX
activity and especially pollen from samples drawn from drums allderived from the same source.

Table 2Micronutrient and Pollen Contents and Antioxidant
Capacity (ORAC) of Blended Raw Honeyvs. Blended Processed Honey
BlendedRaw Honey(meansd)

Calcium (mg)Magnesium (mg)

Statistical Analyses: Descriptive statistics include means
and standard deviations. Differences in micronutrient, AOX
and pollen contents between blended raw honey andblended processed honey were analyzed using paired Ttests.

±± 0.25
1.38 ± 0.88
12.58 ± 1.72
0.017 ± 0.003

Calcium (mg)°PB(meansd)

Potassium (mg)
Pyridoxine (mg)±3.47 ± 0.04
1.33 ± 0.00
13.00 ± 0.14
0.016 ± 0.000±± 0.06
1.5 ± 0.00
14.40 ± 0.65
0.015 ± 0.014
3.57< 0.012< 0.012

Folate (υg)<6<6ORAC (υmol TE/g)hydrophilic
lipophilic

70863.5
1.38
1.10
0.221

± 11614.2± 0.09±0.00± 0.018

Additional research is warranted to examine themechanisms underlying the effects of processing.

BlendedProcessed Honey(meansd)

B12 (υg)
Pollen (grains/10 g)

There are a number of possible reasons for the increases
seen in mineral content and AOX capacity after
processing including:
1.The inherent variability of micronutrient content andAOX capacity in honey samples may make the use ofaverages unsuitable in a study of this type.
2.The process of heating honey may eliminate moisture,
thereby increasing the concentration of minerals andantioxidants.
3.Diatomaceous earth (used for filtration) may increase
the concentration of minerals and antioxidants in honey.

0*

1.44
1.23
0.215

± 0.03± 0.04± 0.004* P<0.05

Processing significantly reduced the pollen content of thehoney (P<0.05), but did not significantly affect the
micronutrient content or AOX activity.

CONCLUSION
Traditional commercial processing significantly reduced
the pollen content of honey but did not significantly impact
the vitamin or mineral content or AOX activity, indicatingthat the micronutrient and antioxidant profile of honey is
not related to its pollen content.
**Funded by the National Honey Board