Who does the chemical analysis of honey? Research work “Study of the properties of honey from grandfather’s apiary. How much will you have to pay for verification?

Honey is not a cheap product. For example, honey in combs costs 1,100 rubles per kg. The most expensive are monofloral honeys: chestnut - 760 rubles. per kg, buckwheat - 680-860 rubles, linden from Bashkiria - 760-850 rubles. And even Altai flower honey costs 850 rubles. No wonder honey is faked. However, the only way to get a 100% correct answer regarding the quality of honey is to take it to a laboratory. No traditional methods can compare with those carried out in laboratory conditions.

How is honey quality analyzed?

Laboratory analysis is designed to reveal the naturalness of honey and compliance with its processing technology. To do this, two main indicators are measured: diastase number and hydroxymethylfurfural (OMF) content. If the honey is overheated or is old, then the OMF content in it will increase, and diastase, on the contrary, will decrease. If honey has been stored for 120 days, there will be 2 times less diastase in it, even with proper storage. Also, the value of the diastase number can be used as an indirect confirmation of the botanical origin of honey.

For example, the analysis of five randomly selected jars of honey, purchased in different places and from different manufacturers, was carried out in the Apis Analytical Center laboratory. He showed:

Acacia honey (Kranodar region, purchased at the honey market in the city of Pshada)

Krasnodar honey, sold as acacia honey, turned out to be flower honey. No traces of acacia pollen were found in it. The diastase number was elevated.

Flower honey (bought in Mozhaisk, at the market from a local beekeeper)

Due to the low level of diastase, this honey was considered old - it is about two years old.

Buckwheat honey (Altai Republic, Gorno-Altaisk, produced in a private apiary)

Buckwheat honey did not contain pollen (according to GOST, its content should be at least 30%, but it turned out to be 24%). This type of honey is considered flower honey. In addition, the analysis showed that the honey was subjected to heat treatment. They did this by violating technology and temperature conditions: they heated the honey at a temperature of more than 50 degrees or for too long. Because of this, the TMF indicator turned out to be elevated (with a norm of no more than 25 mg per kg, it was 30.8). Also, as a result of heating, the amount of enzymes in honey decreased, as shown by an analysis of the diastase number - with a norm of 18, the diastase was 15.3 units.

Flower honey, herbs (Orekhovo-Zuevsky district, village Novoe, purchased in store)

Like buckwheat honey, it was subjected to incorrect, too long heat treatment, as evidenced by the GMF indicator, which turned out to be greatly overestimated and amounted to 42.8 (with a norm of 25 mg per kg). Diastasis in this honey, on the contrary, turned out to be reduced - only 5.8 units, instead of the required 7.

Flower honey, mountain honey (bought in a chain supermarket)

This honey turned out to be the only sample that met all the necessary indicators.

Thus, if you purchase a large quantity of honey and want a quality product, it is best to take a sample for laboratory analysis.

Preparation of honey solution. Laboratory studies of honey are carried out in aqueous solutions and only when determining the water content refractometrically, natural honey is used. For quantitative biochemical studies, prepare a 0.25-10% honey solution in terms of dry matter. Determining water content with a hydrometer and staging some qualitative reactions require more concentrated solutions of honey (1:2).

Preparation of honey solution in terms of dry substances. Calculation is done using formulas 1 ta. 2.

X - (t V) C, (1)

where X is the amount of honey solution of a given concentration in terms of dry substances, ml;

m - honey sample, g;

B is the amount of dry matter in honey, %;

C is the specified concentration of honey solution, %.

X l = X-m 1 (2)

where Xj is the amount of water for preparing a honey solution with % concentration, ml;

X is the amount of honey solution of a given concentration in

in terms of dry matter, ml;

m - weighed amount of honey, g.

Example. From a sample of honey weighing 6 g and containing 20% ​​water, you need to prepare a 20% solution. This honey contains 80% dry matter (100% - 20% = 80%). The total amount of 10% solution from the indicated sample of honey will be

(6 80)/10 = 48 ml!

To prepare a 10% honey solution from a 6 g sample, 42 ml of water is required (48 - 6 = 42 ml).

Preparation of honey solution 1:2. One weighed portion of honey is dissolved in two parts of water.

at Determination of water content and dry residue by specificmu weight of honey solution. Prepare a 1:2 honey solution. To do this, weigh out 100 g of well-mixed honey and dissolve it in 200 ml of distilled water at a temperature of 30-40°C. The prepared solution is cooled to 15°C and its specific gravity is determined. The amount of water and dry residue is determined according to the table. 17.

Example. If the specific gravity of a 1:2 honey solution at 15°C is 1.116, then according to the table this corresponds to 27.13% of the dry residue, and since the honey was diluted three times, its dry residue will be 27.13 3 = 81.39% , and the water content is 100 - 81.39 = 18.61%.

Table 17

Amount of dry honey residue at different specific gravity of honey (1:2)

Determination of water content in honey by refractive index

carried out using a refractometer RDU or RL, previously adjusted with distilled water. A drop of liquid honey is applied to the lower prism of the refractometer and the refractive index is measured. The water content in the honey under study is determined according to the table. 18.

Corrections to temperatures. At temperatures above 20°C, add 0.00023 per 1°, and at temperatures below 20°C, subtract 0.00023 per 1°.

Note: before examination, crystallized honey is heated in a water bath at a temperature of 60°C until completely melted and examined after cooling.

Table 18 Determination of water content in honey by refractive index

Determination of optical activity. Honey carbohydrates are optically active and have the ability to rotate the plane of polarized light. Flower honey rotates the plane of polarized light to the left, and honeydew and some counterfeits (sugar honey, cane sugar, molasses - to the right.

To determine optical activity, use a portable polarimeter type P-161 or a universal saccharimeter SU-3. Before starting measurements, the device is adjusted. Then a polarimetric cuvette (tube) filled with a filtered 10% solution of the honey being studied is inserted into the chamber, which changes the uniformity of the halves of the field of view. By rotating the ratchet, the uniformity of the halves of the field of view is equalized and the scale readings are counted 5 times with a vernier. The arithmetic mean of 5 measurements will be the result of the measurement as a whole.

Determination of mechanical impurities. On a metal mesh with a cell diameter of no more than 1 mm, placed on a glass, place

add about 50 g of honey. The glass is placed in a heated drying cabinet up to 60°C. If there is no cabinet, honey is heated to 60°C in a water bath and then filtered through a mesh. Honey must be filtered without any visible residue.

Determination of total acidity. Total acidity of honeydepends on the content of various acids, salts, proteins and twocarbon monoxide. This indicator is expressed as normaldosami (milliequivalents) is the amount of ml of 0.1 N solutionsodium hydroxide used for titration of 100 g of honey with an indicatorphenolphthalein.

Measure 100 ml of a 10% honey solution into a beaker,add 5 drops of 1% alcohol solution of phenolphthalein and titresoak in 0.1 N sodium hydroxide solution until slightly pink in color(10 s). The discrepancy between determinations should not exceed ±0.05 normal degrees.

Determination of minerals (ash). Contentsneral substances are reduced in honey when sugar is added to itroses, glucose, artificially inverted sugar.

A sample is taken into a crucible calcined to constant weight5-10 g, with an accuracy of 0.1 g, which is charred until blackened gas burner or electric stove. Then the sample is heated for an hour at a temperature of 600°C (red heat). Crucible ooh leave in a desiccator over sulfuric acid for 30 minutes andweighed. The total amount of minerals is calculatedaccording to the formula

X= (nij- m 0 ): m 100, WhereX- total amount of ash,%;

t 0 - crucible weight, g;

j- weight of the crucible with ash, g;

t - weighed amount of honey, g.

Determination of diastase activity. Diastase (amylase-naya) activity is very low in some types of natural honey(white acacia, fireweed, clover, linden, sunflower- vyy). When honey is heated above 50°C and stored for a long time (more than a year), diastava is partially or completely inactivated. Adulteration of honey also leads to a weakening of fer activity cop.

Determination of diastase activity is based on the ability toThis enzyme breaks down starch into amylodextrins. Quantitativebut this indicator is expressed in diastase numbers (Gothe units),which indicate the number of ml of 1% starch solution, splitdiastase contained in 1 g of honey (in terms of dry

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substances) for one hour at a temperature of 40°C ± 1°C tosubstances that are not stained blue by iodine.

A 10% honey solution and other components are poured into 11 test tubes.you according to the table. 19.

The test tubes are capped, the contents are mixed, andplaced in a water bath for 1 hour at a temperature of 40°C ± 1°C, then removed from the water bath and cooled under running water to room temperature, after which 1 drop of iodine solution (0.5 g of iodine and 1 g of potassium iodide in 100 ml of distillate) is added to each boiled water). In those test tubes where the starch remained undecomposed,dark, a blue color appears, in the absence of starch - darkcotton wool, partially decomposed - purple.

Table 19

The procedure for preparing test tubes with honey solution and reagents for determining diaetase activity

The last weakly colored test tube before the discolored test tube (with a yellowish tint) corresponds to the diastase activity of the tested honey (see Table 19).

If there is no soluble starch, it can be prepared in the following way: rinse 250 g of potato starch in 1.l distilled water, let it settle and drain the water. 1.5 liters of 4% hydrochloric acid solution is poured into the sediment and left for 1-2 hours, then the mixture is filtered. The starch collected from the filter is washed repeatedly with distilled water until it is neutral to litmus and dried at a temperature of 90°C.

Due to the fact that the diastase number for natural honey varies in different zones of the country, it is set locally by the regional (regional) veterinary and agricultural departments of the regional (regional) administration, but in all zones it must be no lower than 5.

-/■■ Determination of invert sugar. The total content of glucose and fructose in honey is usually referred to as invert sugar. The amount of invert sugar in honey less than 70% indicates its falsification. However, a normal amount of invert sugar does not guarantee the naturalness of the product.

Preparation of honey solution. A 10% aqueous solution is prepared from the honey being tested, then a 0.25% solution is prepared from this solution; for this, 5 ml of a 10% honey solution is measured into a 200 ml volumetric flask, adjusted to the mark with water and mixed.

Progress of determination. 10 ml of a 1% solution of red blood salt K 3 Fe(CN) 6, 2.5 ml of a 10% solution of sodium hydroxide, 5 ml of a 0.25% solution of honey and 1 drop of a 1% solution of methylene blue are measured into the flask. The mixture is heated to a boil and, at constant low boiling, titrated with the test 0.25% honey solution until the blue (and by the end of the reaction slightly violet) color disappears.

The reduction of methylene blue by reducing substances in honey occurs with some delay, so titration should be done at a rate of no more than one drop every 2 s. Resumption of color after the mixture has cooled is not taken into account. Titration is carried out 2-3 times and the average value is obtained. The discrepancy between parallel studies should not exceed 1%.

Note. If the contents of the flask become discolored without titration, this indicates that the honey in question contains more than 81.2% invert sugar. The content of invert sugar in honey is determined according to the table. 20.

Table 20 Invert sugar content in honey

End of table. 20

Accounting for the reaction: a) greenish-dirty or yellow color - negative; b) orange or slightly pink - weakly positive (observed when honey is heated); c) red, cherry-red, orange, quickly turning into red - positive (honey contains an admixture of artificially inverted sugar).

Determination of the limiting content of inverted calciumhara. 10 ml of a 1% solution of red blood salt, 2.5 ml of a 10% solution of sodium hydroxide and 5.8 ml of a 0.25% solution of the honey under study are measured into the flask. The contents of the flask are heated to boiling. Boil for 1 minute and add 1 drop of 1% methylene blue solution. If the liquid does not discolor, the honey inverted sugar in the test is less than 70% - such honey is adulterated.

Determination of artificially inverted calcium admixturehara. To determine the admixture of artificially inverted sugar in honey, a reaction is used based on the fact that when cane (beet) sugar is converted into inverted sugar by means of acids, part of the levulose (fruit sugar) is destroyed, resulting in the formation of hydroxymethylfurfural, soluble in water, which in the presence of concentrated hydrochloric acid and resorcinol gives a cherry-red color.

Take 4-6 g of honey into a porcelain mortar, add 5-10 ml of ether and grind thoroughly with a pestle. The ethereal extract is poured into a porcelain cup or onto a watch glass and 5-6 crystals of resorcinol are added, which can be added to a mortar during the preparation of the extract. The ether is evaporated at room temperature. Then 1-2 drops of concentrated hydrochloric acid (specific gravity 1.125) are applied to the dry residue.

Determination of sucrose (cane sugar). Into the flask 200 ml measure 5 ml of 10% honey solution and 45 ml of water. After inserting a thermometer into the flask, place it in a water bath, which is preheated to 80°C. Adjust the temperature of the contents flasks to 68-70°C, quickly add 5 ml of hydrochloric acid at a timedilution 1:5, mix by shaking, keep at thistemperature for 5 minutes and immediately cool to 16-18°C. Before the dareremoving the thermometer from the flask, pre-rinse it with disTilled water. Invert is neutralized with a 10% caustic solutionsodium with methyl orange indicator (1-2 drops) until orange-yellow color.

The invert volume is adjusted to 200 ml and inverted three timesStir the resulting 0.25% honey solution by stirring the flask. The determination of inverted sugar in this solution is carried out as described above (determination of inverted sugar).

C =(X- U) 0.95,where C is the sucrose content in honey, %;

X- content of inverted sugar after inversion, %;

Determination of sucrose (cane sugar) impurity. Atfalsification of honey with sucrose worsens organoleptic properties, ponydiastase activity, mineral content andinvert sugar, and the amount of cane sugar increaseshesitating. The counterfeit has right rotation. Investigatorbut to detect this type of falsification it is necessary todetermine organoleptic characteristics, diastase activity,ash content, cane and invert sugar, optical activity.

Definition of sugar honey. Sugar (feeder, exp.resny) “honey” is obtained by feeding bees with sugar syrup. This honey is counterfeit.

Freshly pumped sugar “honey” has a liquid consistency, light color, mild aroma, characteristic of natural No honey has any astringency. Chemical indicators for sa chahar “honey” is as follows: total acidity is not more than one normal degree, ash content is below 0.1%, cane sugar content is above 5%, the counterfeit has a right rotation.

Determination of honey warming. Honey is heated for decrystallization, termination of fermentation and falsification. At the same timeorganoleptic characteristics deteriorate - honey darkens and weakensaroma, caramel taste appears, enzymatic activity decreases

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activity and bactericidal activity, content of hydroxymethylfurfuralis being identified. Based on the above, to determine the spoilage of honeyheating should determine organoleptic characteristics, fermental activity, hydroxymethylfurfural content.

Determination of honey fermentation. This type of yorchi is a trace consequences of storing honey with a water content above 21%. Honey has a pronounced hygroscopicity, therefore its storage in non-sealed containers under conditions of high ambient humidity leads to an increase in the water content in honey, as a result osmophilic yeast is activated and honey begins to ferment.

At the beginning of fermentation, an increase in aroma is noted, thenThere is a sour smell that intensifies when the honey is heated. Honeyswells, foam appears on the surface, and in the mass of honey -gas bubbles. When microscopying such honey, we foundThere are fermentation agents - yeast. h -

Determination of beet (sugar) molasses impurities. Beforeadding beet molasses to honey degrades its organoleptic properties,reduces the content of invert sugar and diastase acactivity. The mixture has a right rotation.

Qualitative reaction: to 5 ml of an aqueous solution of honey, apply cooked in a ratio of 1:2, add 5-10 drops of 5% silver nitrate. Cloudiness of the mixture and the appearance of a white precipitate indicate the presence of beet molasses in honey.

Determination of starch syrup impurity. Changes in honeywhen starch syrup is added to it, the changes are similaryams of honey when adding beet molasses.

Qualitative reaction: a 10% barium chloride solution is added dropwise to 5 ml of a filtered aqueous solution of honey, prepared in a ratio of 1:2. Cloudiness and the formation of a white precipitate after adding the first drops of the reagent indicate the presence of starch syrup in the honey.

Determination of starch and flour impurities. Changes in honeywhen adding starch and flour, the changes are similar, indicatednym when adding molasses to honey.

Qualitative reaction: 5 ml of an aqueous solution of honey in the ratio1:2 mixture is heated in a test tube to boiling, cooled to roomtemperature and add 3-5 drops of iodine solution. The emergence of siIts color indicates the presence of starch or flour in honey.

Determination of gelatin impurity. Gelatin is added to honeyto increase viscosity. At the same time, the taste and aroma deteriorate,enzymatic activity and invert sugar content decrease. The amount of protein increases.

Qualitative reaction: add 5-10 drops of a 5% tannin solution to 5 ml of an aqueous solution of honey in a 1:2 ratio. The formation of white flakes indicates the presence of gelatin in honey. The appearance of slight turbidity is assessed as a negative reaction to gelatin.

Determination of the admixture of honeydew honey to flower honey. The presence of honeydew honey is determined by the following reaction: when alcohol is added to a solution of the honey under test, turbidity is formed. Flower honey without an admixture of honeydew does not form cloudiness with alcohol.

Beeswax its composition is a complex organic compound produced in the body of bees by special glands. In apiaries, for preparing wax, they most often use old, black honeycombs or honeycombs that are not suitable for use for some reason, caps cut off from the surface of honeycombs before pumping out honey (bars), and scrapings from hives. Such primary raw materials are called wax raw materials, and the resulting waste after wax melting is called apiary melting.

Apiary hewing cannot be carried out in apiaries that are unfavorable for bee diseases. In such apiaries, wax raw materials must be sterilized or boiled for a long time under the supervision of a veterinarian.

Laboratory studies are carried out in veterinary laboratories, and samples of wax and foundation are sent there in order to identify falsifications, including the determination of impurities of mineral wax.

Propolis. This bee product is called a natural medicine. After honey and wax, it is considered third in value. This substance is sticky, popularly it is called “bee glue”, “wax glue”, “uza”, “yuza”, “bee resin”, and in recent years the word “propolis” has become the most popular. The product has a viscous or hard consistency, with a characteristic resinous, pleasant aroma. Bees prepare it from the resinous plant secretions of some trees. Propolis from different places is of different composition and has different bactericidal and medicinal properties.

Since the technology and hygiene of propolis production are still imperfect, its veterinary and sanitary examination is in its infancy.

Bee venom - a beekeeping product produced by two glands of bees and entering a special reservoir, from where it is thrown out through the sting when stung. The preparation of bee venom and the sale of bees for medicinal purposes by stinging are permitted by a veterinarian only from apiaries that do not have

current infectious diseases of bees. In terms of quality, bee venom is a colorless liquid with a pungent odor and high acidity. Laboratory methods for determining the quality of bee venom include studying its toxicity.

Pollen - beebread. The stamens of living flowers contain many small powdery grains called pollen or microspores. Pollen, folded by bees into the cells of honeycombs and filled with honey, is called beebread. The biological role of pollen in honey has not been studied; pollen with honey is considered an indispensable food for bees.

The lack of pollen in the diet of bees leads to their loss of the ability to produce wax and, in general, their vital functions are disrupted. Therefore, bees, at the same time as preparing honey, also collect pollen, but only from the flowers of plants rich in protein with a certain complex of essential amino acids and biologically active substances. Sometimes pollen and beebread become harmful to bees and cause pollen toxicosis (Fig. 6).

1. General provisions

1.1. Honey is subject to mandatory veterinary and sanitary examination in accordance with the requirements of these Rules.

1.2. Veterinary and sanitary examination of honey is carried out by specialists from the veterinary and sanitary examination laboratory who have undergone appropriate training.

1.3. These Rules are mandatory for all individuals and legal entities involved in the sale of honey in markets, who are responsible for submitting it to the laboratory for research.

2. Veterinary and sanitary requirements

2.1. Honey is accepted for veterinary and sanitary examination if the owner of the apiary has a veterinary and sanitary passport. When selling honey outside the region - a veterinary certificate.

2.2. Honey owners are required to deliver honey for sale in clean containers made from materials approved by the State Committee for Sanitary and Epidemiological Supervision of Russia (stainless steel, aluminum alloys, glass, enamelware and wood, except oak and coniferous trees). Honey delivered in contaminated or containers that do not meet the above requirements is not subject to examination.

2.3. Honeycomb honey is accepted for examination sealed on at least two-thirds of the honeycomb area. The honeycomb should be a uniform white or yellow color.

3. Sampling

3.1. Samples for analysis are taken by workers of the veterinary examination laboratory in the presence of the owner of the honey according to the methods outlined in the Appendix (section 1) from each delivered container.

3.2. For research in the laboratory of veterinary and sanitary examination, one-time samples of honey weighing 100 g are taken from each delivered unit at the market; when determining the mass fraction of water with a hydrometer, the mass of the honey sample is doubled.

3.3. Samples of honey in frames are taken from every fifth comb frame measuring 5 x 5 cm. Samples of comb honey removed from the frames are taken in the same sizes from each package.

3.4. When conducting additional studies of honey in a veterinary laboratory, the sample must be at least 500 g. In this case, the honey sample is sealed, one half is sent to the veterinary laboratory, and the second is stored until the results of the study are obtained (as a control).

3.5. The containers for samples taken must meet sanitary requirements and be closed with glass, cork stoppers or screw caps.

4. The procedure for conducting veterinary and sanitary examination

4.1. To determine the quality of honey, the laboratory of veterinary and sanitary examination conducts research on the following indicators:

• organoleptic data (color, aroma, taste, consistency and crystallization);
• mass fraction of water;
• the presence of hydroxymethylfurfural (OMF);
• diastase (amylase) activity;
• determination of pollen;
• general acidity;
• mass fraction of reducing sugar;
• sucrose content (according to indications);
• presence of mechanical impurities (according to indications);
• content of radioactive substances.
• Research on these indicators is carried out according to the methods outlined in the Appendix.

4.2. Natural honey in terms of organoleptic indicators must meet the following requirements: