CODEX STAN
12-1981 Rev. 1 (1987)

Contents - Previous

 CODEX STANDARD FOR HONEY
(World-wide standard)5

1. SCOPE

1.1 This standard applies to all honeys produced by honeybees and covers all styles of honey presentation which are offered for direct consumption.

1.2 The standard also covers honey which is packed in non-retail (bulk) containers and is intended for re-packing into retail packs.

2. DEFINITION

2.1 Definition of Honey

Honey is the natural sweet substance produced by honeybees from the nectar of blossoms or from secretions of living parts of plants or excretions of plant sucking insects on the living parts of plants, which honeybees collect, transform and combine with specific substances of their own, store and leave in the honey comb to ripen and mature.

2.2 Description

Honey consists essentially of different sugars predominantly glucose and fructose. The colour of honey varies from nearly colourless to dark brown. The consistency can be fluid, viscous or partly to entirely crystallized. The flavour and aroma vary, but usually derive from the plant origin.

2.3 Subsidiary Definitions and Designations

2.3.1 Origin

2.3.1.1 Blossom Honev or Nectar Honey is the honey which comes from nectaries of flowers.

2.3.1.2 Honeydew Honey is the honey which comes mainly from secretions of living parts of plants or excretions of plant sucking insects on the living parts of plants. Its colour various from very light brown or greenish to dark brown.

2.3.2 Methods of Processing

2.3.2.1 Extracted Honey is honey only obtained by centrifuging decapped broodless combs.

2.3.2.2 Pressed Honey is honey obtained by pressing broodless combs with or without the application of moderate heat.

2.3.2.3 Drained Honey is honey obtained by draining decapped broodless combs.

2.3.3 Styles - Honey which meets all the compositional and quality criteria of Section 3 of this standard may be presented as follows:

(a) Honey which is honey in liquid or crystalline state or a mixture of the two;

(b) Comb Honey which is honey stored by bees in the cells of freshly built broodless combs and which is sold in sealed whole combs or sections of such combs

(c) Chunk Honey which is honey containing one or more pieces of comb honey;

(d) Crystallized or Granulated Honey which is honey that has undergone a natural process of solidification as a result of glucose crystallization;

(e) Creamed (or creamy or set) Honey is honey which has a fine crystalline structure and which may have undergone a physical process to give it that structure and to make it easy to spread.

3. ESSENTIAL COMPOSITION AND OUALITY FACTORS

3.1 Honey shall not have any objectionable flavour, aroma, or taint absorbed from foreign matter during its processing and storage. The honey shall not have begun to ferment or effervesce.

3.2 Honey shall not be heated to such an extent that its essential composition and quality is impaired.

3.3 Apparent reducing sugar content, calculated as invert sugar:

(a) Honey not listed below - Not less than 65%
(b) Honeydew honey - Not less than 60%
(c) Blackboy (Xanthorrhoea preissii) - Not less than 53%

3.4 Moisture Content

(a) Honeys not listed below

-

Not more than 21%
(b) Heather honey (Calluna)

-

Not more than 23%
(c) Clover honey (Trifolium)

-

Not more than 23%

3.5 Apparent Sucrose Content

(a) Honeys not listed below

-

Not more than 5%
(b) Honeydew honey, blends of honeydew honey and blossom honey, Robinia, Lavender, Citrus, Alfalfa, Sweet-clover, Red Gum (Eucalyptus Camaldulensis), Acacia, leatherwood (Eucryphia Lucinda), Menzies Banksia (Banksia menziesii)

-

Not more than 10%
(c) Red Bell (Calothamnus sanguineus), White stringy bark (Eucalyptus scabra), Grand Banksia (Banksia grandis), Blackboy (Xanthorrhoea preissi)

-

Not more than 15%

3.6 Water Insoluble Solids Contents

(a) For honeys other than pressed honey

-

Not more than 0.1%
(b) Pressed honey

-

Not more than 0.5%

3.7 Mineral Content (ash)

(a) Honeys not listed below

-

Not more than 0.6%
(b) Honeydew honey or a mixture of honeydew honey and blossom honey

-

Not more than 1.0%

 

3.8 Acidity

-

Not more than 40 milliequivalents acid per 1000 grammes

3.9 Diastase Activity

Determined after processing and blendig in accordance with Section 7.7

-

Not more than 3

 

3.10 Hydroxymethylfurfural Content

-

Not more than 80 mg/kg

4. FOOD ADDITIVES

4.1 None permitted.

5. HYGIENE

5.1 It is recommended that the product covered by the provisions of this standard be prepared in accordance with the appropriate sections of the General Principles of Food Hygiene recommended by the Codex Alimentarius Commission (Ref. No. CACIRCP 1-1969, Rev. 2 (1985)).

5.2 Honey should be free from visible mould and, as far as practicable, be free from inorganic or organic matters foreign to its composition, such as, insects, insect debris, brood or grains of sand, when the honey appears in retail trade or is used in any product for human consumption.

5.3 Honey shall not contain toxic substances arising from microorganisms or plants in an amount which may constitute a hazard to health.

6. LABELLING

In addition to Sections 2, 3, 7 and 8 of the General Standard for Labelling or Prepackaged Foods (CODEX STAN 1~1985)6 the following specific provisions apply:

6.1 The Name of the Food

6.1.1 Subject to the provisions of 6.1.4 products conforming to the standard shall be designated "honey".

6.1.2 No honey may be designated by any of the designations in Section 2.3 unless it conforms to the appropriate description contained therein. The Styles in 2.3.3 (a), (c), (d) and (e) shall be declared.

6.1.3 Honey may be designated by the name of the geographical or topographical region if the honey was produced exclusively within the area referred to in the designation.

6.1.4 Honey may be designated according to floral or plant source if it comes wholly or mainly from that particular source and has the organoleptic, physicochemical and microscopic properties corresponding with that origin.

6.1.5 Honey complying with Sections 3.3(b) and (c), 3.4(b) and 3.5(b) and (c) shall have in close proximity to the word YY~~~~yl the common name or the botanical name of the floral source or sources.

6.2 Labelling of Non-Retail Containers

In addition to Sections 2, 3 and 8.1.3 of the General Standard the following specific provisions applies:

6.2.1 Information on labelling as specified in this Section shall be given either on the container or in accompanying documents, except that the name of the product, lot identification, and the name and address of the manufacturer or packer shall appear on the container.

6.2.2 Lot identification, and the name and address of the manufacturer or packer may be replaced by an identification mark provided that such a mark is clearly identifiable with the accompanying documents.

6.2.3 Outer containers holding prepackaged foods in small units (see Section 6 of the General Standard) shall be fully labelled.

7. METHODS OF ANALYSIS AND SAMPLING

7.1 Determination of reducing sugar content (Type I Method)

7.1.1 Principle of method

The method is a modification of the Lane and Bynon (1923) procedure involving the reduction of Soxhlet's modification of Fehling's solution by titration at boiling point against a solution of reducing sugars in honey using methylene blue as an internal indicator.

The maximum accuracy for this type of determination is attained by ensuring that the reduction of the Fehling' 5 solution during the standardization step and in the determination of the reducing sugars in the honey solution are carried out at constant volume. A preliminary titration is, therefore, essential to determine the volume of water to be added before the determinations are carried out to satisfy this requirement.

7.1.2 Reagents

7.1.2.1 Soxhlet's Modification of Fehling's Solution

Solution A: Dissolve 69.28 g copper sulphate pentahydrate (CuSO4.5H20; MW + 249.71) with distilled water to 1 litre. Keep one day before titration.

Solution B: Dissolve 346 g sodium potassium tartrate (C4H4K NaO6.4H20; MW + 282.23) and 100 g sodium hydroxide (NaOH) with distilled water to 1 litre. Filter through prepared asbestos.

7.1.2.2 Standard Invert Sugar Solution (10 gIL)

Weigh accurately 9.5 g pure sucrose, add 5 mL hydrochloric acid ca. 36.5 percent wiw pure HC1) and dilute with water to about 100 mL, store this acidified solution for several days at room temperature (ca. 7 days at 120 to 150C, or 3 days at 200 to 25C), and then dilute to 1 litre. (N.B. Acidified 1.0 percent invert sugar remains stable for several months). Neutralize a suitable volume of this solution with iM sodium hydroxide solution (40 gIL) immediately before use and dilute to the required concentration (2 gIL) for the standardization.

7.1.2.3 Methylene Blue Solution

Dissolve 2 g in distilled water and dilute to 1 litre.

7.1.2.4 Alumina Cream

Prepare cold satured solution of alum (K2504A12 (504)3.24H20) in water. Add ammonium hydroxide with constant stirring until solution is alkaline to litmus, let precipitate settle and wash by decantation with water until wash-water gives only slight test for sulphate with barium chloride solution. Pour off excess water and store residual cream in stoppered bottle.

7.1.3 Sampling

7.1.3.1 Liquid or Strained Honey

If sample is free from granulation, mix thoroughly by stirring or shaking; if granulated, place closed container in water-bath without submerging, and heat 30 mm. at 600C; then if necessary heat at 65 0C until liquefied. Occasional shaking is essential. Mix thoroughly and cool rapidly as soon as sample liquefies. Do not heat honey intended for hydroxymethylfurfural or diastatic determination. If foreign matter, such as wax, sticks, bees, particles of comb, etc., is present, heat sample to 400C in water-bath and strain through cheesecloth in hot-water-funnel before sampling.

7.1.3.2 Comb Honey

Cut top of comb, if sealed, and separate completely from comb by straining through a sieve the meshes of which are made by so weaving wire as to form square opening of 0.500 mm by 0.500 mm7 when portions of comb or wax pass through sieve, heat sample as in 7.1.3.1 and strain through cheesecloth. If honey is granulated in comb, heat until wax is liquefied; stir, cool and remove wax.

7.1.4 Procedure

 7.1.4.1 Preparation of Test Sam~le - First Procedure (applicable to honeys which may contain sediment)

(a) Transfer an accurately weighed sample of approximately 25 g (W1) from the homogenized honey to 100 mL volumetric flask, add 5 mL alumina cream (7.1.2.4) dilute to volume with water at 200C and filter.

(b) Dilute 10 mL of this solution to 500 mL with distilled water (diluted honey solution).

OR

7.1.4.2 Pre aration of Test Sam le - Second Procedure

(a) Weight accurately a representative quantity of about 2 g (W2) of the homogeneous honey sample, dissolve in distilled water and dilute to 200 mL in a calibrated flask (honey solution).

(b) Dilute 50 ml of the honey solution to 100 mL using distilled water (diluted honey solution).

7.1.4.3 Standardization of the Modified Fehlin~'s Solution

Standardize the modified Fehling' 5 solution A so that exactly 5 mL (pipette), when mixed with approximately 5 mL of Fehling's solution B, will react completely with 0.050 g invert sugar added as 25 mL dilute invert sugar solution (2 gIL).

7.1.4.4 Preliminary Titration

The total volume of the added reactants at the completion of the reduction titration must be 35 mL. This is made up by the addition of a suitable volume of water before the titration commences. Since the compositional criteria of the honey standard specify that there should be more than 60 percent reducing sugars (calculated as invert sugar) a preliminary titration is necessary to establish the volume of water to be added to a given sample to ensure the reduction is carried out at constant volume. This volume of water to be added is calculated by subtracting the volume of diluted honey solution consumed in the preliminary titration (c mL) from 25 mL.

Pipette 5 mL Fehling's solution A into a 250 mL Erlenmeyer flask and add approximately 5 mL Fehling's solution B. Add 7 mL distilled water, a little powdered pumice or other suitable antibumping agent, followed by about 15 mL diluted honey solution from a burette. Heat the cold mixture by boiling over a wire gauze, and maintain moderate ebullition for 2 mm. Add 1 mL 0.2 percent aqueous methylene blue solution whilst still boiling and complete the titration within a total boiling time of 3 minutes, by repeated small additions of diluted honey solution until the indicator is decolorized. It is the colour of the supernatant liquid that must be observed. Note the total volume of diluted honey solution used (x mL).

 7.1.4.5 Determination

Calculate the amount of added water necessary to bring the total volume of the reactants at the completion of the titration to 35 mL by subtracting the preliminary titration (x mL) from 25 mL.

Pipette 5 mL Fehling's solution A into a 250 mL Erlenmeyer flask and add approximately 5 mL Fehling's solution B.

Add (25-x) mL distilled water, a little powdered pumice or other suitable antibumping agent and, from a burette, all but 1.5 mL of the diluted honey solution volume determined in the preliminary titration. Heat the cold mixture to boiling over a wire gauze and maintain moderate ebullition for 2 mm. Add 1.0 mL 0.2 percent methylene blue solution whilst still boiling and complete the titration within a total boiling time of 3 mm. by repeated small additions of diluted honey solution until the indicator is decolorized. Note the total volume of diluted honey solution (y mL). Duplicate titrations should agree within 0.1 mL.

7.1.5 Calculation and Expression of Results

7.1.5 Calculation and Expression of Results

Where the First Procedure (7.1.4.1) has been used:

C =

----

X

----

Wher the Second Procedure (7.1.4.2) has been used:

C =

----

X

----

 

Where

C

= g invert sugar per 100 g honey

W1

= weight (g) of honey sample taken according to sub-section

W2

= weight (g) of honey sample taken according to sub-section 7.1.4.2

Y1

= volume (mL) of diluted honey solution consumed in the determination carried out according to the First Procedure (7.1.4.1)

Y2

= volume (mL of diluted honey solution consumed in the determination carried out according to the Second Procedure (7.1.4.2)

7.1.6 Notes on the Procedure

It is essential to the accuracy and repeatability of the determination that the volume of water necessary to bring the reactant mixture to a total volume of 35 mL be determined for each individual sample; the following table gives typical volumes which may be encountered at the preliminary titration stage for the incremental contents of invert sugar shown, assuming the test sample (7.1.4.1) weighs about 25 g or test sample (7.1.4.2) weighs about 2 g.

Invert Sugar content
%

Volume of Distilled Water to be Added
mL

60

65

70

75

8.3

9.6

10.7

11.6

7.2 Determination of Apparent Sucrose Content (Type I Method)

7.2.1 Principle of the Method

Based on the Walker (1917) inversion method.

7.2.2 Reagents

7.2.2.1 Soxhlet modification of Fehling's solution (7.1.2.1)

7.2.2.2 Standard invert sugar solution (7.1.2.2)

7.2.2.3 Hydrochloric acid (6.34 M aqueous)

7.2.2.4 Sodium hydroxide solution 2 gIl litre (7.1.2.3)

7.2.2.5 Methylene blue solution 2 gIl litre (7.1.2.3)

7.2.3 Sampling

The honey is prepared for sampling as in 7.1.3

7.2.4 Procedure

7.2.4.1 Preparation of test sample

Prepare the honey sample as in 7.1.4.1(a). Dilute 10 mL of this solution to 250 mL with distilled water: honey solution (for sucrose determination) OR prepare the honey solution as in 7.1.4.2(a).

7.2.4.2 Hydrolysis of the test samnle

The honey solution (50 mL) is placed in a 100 mL graduated flask, together with 25 mL distilled water; heat the test sample to 65 0C over a boiling water-flask. The flask is then removed from the water-bath and 10 ml of 6.34 M hydrochloric acid added. The solution is allowed to cool naturally for 15 minutes, and then brought to 200C and neutralizing with 5 M sodium hydroxide, using litmus paper as indicator, cooled again, and the volume adjusted to 100 mL (diluted honey solution).

7.2.4.3 Titration

As in 7.1.4.4 and 7.1.4.5.

7.2.5 Calculation and expression of results

Calculate percent invert sugar (g invert sugar per 100 g honey) after inversion using the appropriate formula as percent invert sugar before inversion in 7.1.5.

Apparent sucrose content

=

(invert sugar content after inversion minus invert sugar content before inversion ) X 0.95

The result is expressed as g apparent sucrosell00 g honey.

7.3 Determination of Moisture Content (Type I Method)

7.3.1 Principle of Method

Based on the refractometric method of Chataway (1932), revised by Wedmore (1955).

7.3.2 Apparatus

Refractometer

7.3.3 Sampling

The honey is prepared for sampling as in 7.1.3.

7.3.4 Procedure

7.3.4.1 Determination of the Refractive Index

Determine the refractive index of the test sample using a refractometer at a constant temperature near 200C. Convert the reading to moisture content (percent mim) using the table given below. If the determination is made at a temperature other than 200C, convert the reading to standard temperature of 200C, according to ~he temperature corrections quoted. The method used is to be noted in the test report.

TABLE FOR THE ESTIMATION OF MOISTURE CONTENT

Refractive
Index
(20C)

Moisture
Content
(percent)

Refractive
Index
(20)

Moisture
Content
(percent)

Refractive
Index
(20C)

Moisture
Content
(percent)

1.5044

1.5038

1.5033

1.5028

1.5023

1.5018

1.5012

1.5007

1.5002

1.4997

1.4992

1.4987

1.4982

1.4976

1.4971

1.4966

1.4961

1.4956

1.4951

1.4946

1.4940

13.0

13.2

13.4

13.6

13.8

14.0

14.2

14.4

14.6

14.8

15.0

15.2

15.4

15.6

15.8

16.0

16.2

16.4

16.6

16.8

17.0

1.4935

1.4930

1.4925

1.4920

1.4915

1.4910

1.4905

1.4900

1.4895

1.4890

1.4885

1.4880

1.4875

1.4870

1.4865

1.4860

1.4855

1.4850

1.4845

1.4840

1.4835

17.2

17.4

17.6

17.8

18.0

18.2

18.4

18.6

18.8

19.0

19.2

19.4

19.6

19.8

20.0

20.2

20.4

20.6

20.8

21.0

21.2

1.4830

1.4825

1.4820

1.4815

1.4810

1.4805

1.4800

1.4795

1.4790

1.4785

1.4780

1.4775

1.4770

1.4765

1.4760

1.4755

1.4750

1.4745

1.4740

21.4

21.6

21.8

22.0

22.2

22.4

22.6

22.8

23.0

23.2

23.4

23.6

23.8

24.0

24.2

24.4

24.6

24.8

25.0

7.3.4.2 Temperature Corrections - Refractive Index:

Temperatures above 20C - Add 0.00023 per C
Temperatures below 20C - Subtract 0.00023 per C

7.4 Gravimetric Determination of Water-insoluble Solids Content (Type II Method)

7.4.1 Sampling

The honey is prepared for sampling as in 7.1.3.

7.4.2 Procedure

7.4.2.1 Preparation of Test Sample

Honey (20 g) is weighed to the nearest centigram (10 mg) and dissolved in a suitable quantity of distilled water at 800C and mixed well.

7.4.2.2 Gravimetric Determination

The test sample is filtered through a previously dried and weighed fine sintered glass crucible (pore size 15.40 ~m) and washed thoroughly with hot water (800C) until free from sugars (Mohr test). The crucible is dried for one hour at 135 0C, cooled and weighed to 0.1 mg.

7.4.3 Expression of Results

The result is expressed as percent water-insoluble solids (m/m).

7.5 D~ination of Mineral Content ash (Type I Method)

7.5.1 Sampling

Honey is prepared for sampling as in 7.1.3.

7.5.2 Procedure

7.5.2.1 I~mtionofthe Honev

Honey (5010 g) is weighed accurately into an ignited and pre-weighed platinum or silica dish and gently heated in a muffle furnace until the sample is black and dry and there is no danger of loss by foaming and overflowing. An infra-red lamp can also be used to char the sample before inserting into the furnace. If necessary, a few drops of olive oil may be added to prevent frothing. The sample is then ignited at 6000C to constant weight. The sample is cooled before weighing.

7.5.3 Expression of Results

The result is expressed as percent ash (mim).

7.6 Determination of Acidity (Type II Method)

7.6.1 Sampling

The honey is prepared for sampling as in 7.1.3.

7.6.2 Reagents

7.6.2.1 Sodiumhdroxide0.1N (carbonate-free)

7.6.2.2 Phenolnhthalein indicator 1 percent (mlv) in ethanol, neutralized.

7.6.2.3 Distilled Water made carbon dioxide free by boiling and subsequent cooling.

7.6.3 Procedure

7.6.3.1 Preparation of Test Sample

Honey (10.0 g) is weighed accurately and dissolved in 75 mL distilled water

(7.6.2.3).

7.6.3.2 Titration

The test sample is titrated against carbonate-free 0.1 M sodium hydroxide solution using 4-5 drops of neutralized phenolphthalein indicator. The end-point colour should persist for 10 seconds. For darkly coloured samples, a smaller weight should be taken. As an alternative, a pH meter may be used and the sample titrated to pH 8.3.

7.6.4 Calculation and Expression of Results

The result is expressed as millival (milli-equivalents acid/kg honey and is calculated as follows:

Acidity = 10 v

where v = the number of mL 0.1 M NaOH used in the neutralization of 10 g honey.

7.7 Determination of Diastase Activit (Type I Method)

7.7.1 Principle of the Method

Based on the method of Schade et al., (1985) modified by White et al., (1959) and Hadorn (1961).

7.7.2 Reagents

7.7.2.1 Iodine Stock Solution:

Dissolve 8.8 g of iodine analytical grade, in 30-40 mL water containing' 22 g potassium iodine, analytical grade, and dilute to 1 litre with water.

7.7.2.2 Iodine solution 0.0007 N:

Dissolve 20 g potassium iodine, analytical grade, in 30-40 mL water in a 500-mL volumetric flask. Add 5.0 mL iodine stock solution and make up to volume. Make up a fresh solution every second day.

7.7.2.3 Acetate Buffer - pH 5.3 (1.59M):

Dissolve 87 g sodium acetate.3H20 in 400 mL water, add about 10.5 mL glacial acetic acid in a little water and make up to 500 ml. Adjust the pH to 5.3 with sodium acetate or acetic acid as necessary, using a pH meter.

7.7.2.4 Sodium Chloride Solution 0.5M:

Dissolve 14.5 g sodium chloride, analytical grade, in ;boiled-out distilled water and make up to 500 mL. The keeping time is limited by mould growth.

7.7.2.5 Starch Solution:

(a) Preparation of soluble starch

In a conical flask immersed in a water-bath and fitted with a reflux condenser, boil 20 g of potato starch for one hour in the presence of a mixture of 100 mL of 95 percent ethanol and 7 mL of 1 M hydrochloric acid. Cool, filter through a filtering crucible (pore size 90 - 150 ~m) and wash with water until the wash/water ceases to give any chloride reaction. Drain thoroughly and dry the starch in air at 35 0C. The soluble starch must be stored in a well stoppered flask.

(b) Determination of moisture content of soluble starch

Accurately weigh a quantity of approximately 2 g of soluble starch and spread in a thin layer over the bottom of a weighing bottle (diameter 5 cm). Dry for one and a half hours at 1300C. Allow to cool in a dessicator and re-weigh. The weight loss with respect to 100 g represents the moisture content. The moisture content of such starch should be 7-8% mlm depending on the humidity of the air in which the sample has been dried.

(c) Preparation of starch solution

Use a starch with a blue value between 0.5-0.55 using a 1 cm cell, as determined by the method below. Weigh out the amount of starch which is equivalent to 2.0 g anhydrous starch. Mix with 90 mL of water in a 250 mL conical flask. Bring rapidly to the boil, swirling the solution as much as possible, heating over a thick wire gauze preferably with an asbestos centre. Boil gently for 3 mm., cover and allow to cool spontaneously to room temperature. Transfer to a 100 mL volumetric flask, place in a water bath at 400C to attain this temperature and make up to volume at 40C.

Method for determining blue value of starch

The amount of starch equivalent to 1 g anhydrous starch is dissolved by the above method, cooled and 2.5 mL acetate buffer added before making up to 100 mL in a volumetric flask.

To a 100 mL volumetric flask add 75 mL water, 1 mL M hydrochloric acid and 1.5 mL of 0.02 N iodine solution. Then add 0.5 mL of the starch solution and make up to volume with water. Allow to stand for oneJIour in the dark and read in 1 cm cell using a spectrophotometer at 660 nm against a blank containing all the ingredients except the starch solution. Reading on the absorbance scale = Blue value.

7.7.3 Apparatus

7.7.3.1 Water-bath at 40 + 0.20C.
7.7.3.2 Spectrophotometer to read at 660 rim.

7.7.4 Sampling

The honey sample is prepared as in 7.1.3 without any heating.

7.7.5 Procedure

7.7.5.1 Preparation of test sam les

Honey solution: 10.0 g honey is weighed into a 50 mL beaker and 5.0 mL acetate buffer solution is added, together with 20 mL water to dissolve the sample. The sample is completely dissolved by stirring the cold solution. 3.0 mL sodium chloride solution is added to a 50 mL volumetric flask and the dissolved honey sample is transferred to this and the volume adjusted to 50 mL.

N.B.: It is essential that the honey should be buffered before ;coming into contact with sodium chloride.

Standardization of the starch solution

The starch solution is warmed to 400C and 5 mL pipetted into 10 mL of water at 400C and mixed well. I mL of this solution is pipetted into 10 mL 0.0007 N iodine solution, diluted with 35 mL of water and mixed well. The colour is read at 660 nm against a water blank using a 1 cm cell.

The absorbance should be 0.760 + 0.020. If necessary the volume of added water is adjusted to obtain the correct absorbance.

7.7.5.2 Absorbance determination

Pipette 10 mL honey solution into 50 mL graduated cylinder and place in 400 + 20C water-bath with flask containing starch solution. After 15 minutes, pipette 5 starch solution into the honey solution, mix, and start stop-watch. At 5 minutes intervals remove 1 mL aliquots and add to 10.00 mL 0.0007 N iodine solution. Mix and dilute to standard volume (see 6.7.5.1). Determine absorbance at 660 nm in spectrophotometer immediately using I cm cell. Continue taking 1 mL aliquots at intervals until absorbance of less than 0.235 is reached.

7.7.6 Calculation and expression of results

The absorbance is plotted against time (mm) on a rectilinear paper. A straight line is drawn through at least the last three points on the graph to determine the time when the reaction mixture reaches an absorbance of o.235. Divide 300 by the time in minutes to obtain the diastase number (DN). This number expresses the diastase activity as ml 1 percent starch solution hydrolysed by the enzyme in 1 g of honey in 1 h at 400C. This diastase number corresponds with the Gothe-scale number.

Diastase activity = DN = ml starch solution 1 percent)/g honey/h at 400C.

7.8 Spectrophotometric determination of hydroxymethylfurfural (HMF) content (Type II Method)8

According to the AOAC method (AOAC, 14th Ed., 1984, Hydroxymethylfurfural in Honey, Spectrophotometric Method, 31.153).

 Literature references

Chataway, H.D. (1932), Canad. I. Res. 6,540; (1933) Canad. I. Res. 8, 435; (1935) Canad. Bee 1.43 (8) 215 only.

Hadorn, H. (1961), Mitt. Gebiete Lebens, u. Hyg., 52,67.

Kiermeier, F., Ko~berlein, W. (1954), Z. Unters. Lebensmitt., 98, 329.

Lane, J.H., and Eynon, L. (1923), 1. Soc. Chem. Ind. 42, 32T, 143T, 463T.

Shade, I.E., Marsh, G.L., and Eckert, I.E. (1958), Food Research, 23, 446.

Turner, J.H., Rebers, P.A., Barrick, P.L. and Cotton, R.H. (1954), Anal. Chem. 26, 898.

Walker, H.S. (1917), 1. Ind. Eng. Chem. 2, 490.

Wedmore, E.B. (1955), Bee World, 3;6, 197.

White, I.W., Kushnir, I., and Subors, M.H. (1964), Food Technol. 18, 555.

White, J.W., and Pairent, F.W., (1959), J.A.O.A.C., 421, 344.

Winkler, 0. (1955), Z. Lebensm. Untersuch u. Forsch, 102, 161.

 

5 Supersedes the Codex European Regional Standard for Honey (CODEX STAN 12-1981).

6 Hereafter referred to as "The General Standard"

7 Ref. ISO 565-1983. Such sieve could be replaced by U.S. sieve with No.40 Standard screen (size of opening 0.420 mm).

8 Adopted by the 17 Session of the Commission.

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