IDENTIFICATION METHOD OF MATURITY OF ACACIA HONEY

Abstract

The present disclosure relates to the technical field of food detection, in particular to an identification method of maturity of acacia honey. In the present disclosure, the identification method of maturity of acacia honey includes the following steps: detecting an acacia honey sample using turanose as a characteristic marker; where if the acacia honey sample to be identified has a turanose content of no less than 0.5%, it is determined that the acacia honey sample to be identified is mature acacia honey; if the acacia honey sample to be identified has a turanose content of no less than 0.3% but less than 0.5%, it is determined that the acacia honey sample to be identified is semi-immature acacia honey; and if the acacia honey sample to be identified has a turanose content of less than 0.3%, it is determined that the acacia honey sample to be identified is immature acacia honey.

Claims

1. (canceled)

2. A method for identifying maturity of acacia honey, comprising using turanose as a characteristic marker of mature acacia honey: wherein if the acacia honey sample to be identified has a turanose content of no less than 0.5%, it is determined that the acacia honey sample to be identified is mature acacia honey: if the acacia honey sample to be identified has a turanose content of no less than 0.3% but less than 0.5%, it is determined that the acacia honey sample to be identified is semi-immature acacia honey; and if the acacia honey sample to be identified has a turanose content of less than 0.3%, it is determined that the acacia honey sample to be identified is immature acacia honey.

3. A method for identifying mature acacia honey and immature acacia honey, comprising using turanose as a characteristic marker of mature acacia honey: wherein if the acacia honey sample to be identified has a turanose content of no less than 0.5%, it is determined that the acacia honey sample to be identified is mature acacia honey: if the acacia honey sample to be identified has a turanose content of no less than 0.3% but less than 0.5%, it is determined that the acacia honey sample to be identified is semi-immature acacia honey; and if the acacia honey sample to be identified has a turanose content of less than 0.3%, it is determined that the acacia honey sample to be identified is immature acacia honey.

4. An identification method of maturity of acacia honey, comprising the following steps: detecting an acacia honey sample using turanose as a characteristic marker; wherein if the acacia honey sample to be identified has a turanose content of no less than 0.5%, it is determined that the acacia honey sample to be identified is mature acacia honey; if the acacia honey sample to be identified has a turanose content of no less than 0.3% but less than 0.5%, it is determined that the acacia honey sample to be identified is semi-immature acacia honey; and if the acacia honey sample to be identified has a turanose content of less than 0.3%, it is determined that the acacia honey sample to be identified is immature acacia honey; the mature acacia honey is brewed in a hive for at least 7 d, and shows honeycomb sealing of no less than 75%; the semi-immature acacia honey is brewed in the hive for more than 3 d but no less than 5 d, and shows honeycomb sealing of 30% to 70%; and the immature acacia honey is brewed in the hive for 0 d to 3 d, and shows honeycomb sealing of no more than 10%.

5. The identification method of maturity of acacia honey according to claim 4, wherein the acacia honey sample is detected by an evaporative light-scattering detector (ELSD) through high-performance liquid chromatography (HPLC).

6. The identification method of maturity of acacia honey according to claim 5, wherein a process of detecting the acacia honey sample comprises: detecting the acacia honey sample by the ELSD through the HPLC; plotting a standard curve by a linear relationship between the turanose content and a peak area; according to the standard curve and an obtained peak area of the turanose detected in the acacia honey sample, calculating an turanose content; wherein the turanose content is a mass percentage relative to the acacia honey sample.

7. The identification method of maturity of acacia honey according to claim 5, wherein the detecting by the ELSD through the HPLC is conducted under liquid chromatography (LC) conditions as follows: using a Hi-Plex Pb, USP L19 chromatographic column at a column temperature of 68? C. to 72? C.

8. The identification method of maturity of acacia honey according to claim 7, wherein the Hi-Plex Pb, USP L19 chromatographic column is a 4.0 mm?250 mm column.

9. The identification method of maturity of acacia honey according to claim 7, wherein isocratic elution is conducted using water as a mobile phase.

10. The identification method of maturity of acacia honey according to claim 9, wherein the mobile phase has a flow rate of 0.5 mL/min to 0.7 mL/min and an injection volume of 45 ?L to 55 ?L.

11. The identification method of maturity of acacia honey according claim 5, wherein in the detecting by the ELSD through the HPLC, the ELSD has the following parameters: an atomization temperature of 90? C., an evaporation temperature of 60? C., and a carrier gas flow rate of 1.2 standard litre per minute (SLM).

12. The identification method of maturity of acacia honey according claim 5, further comprising a step of pretreatment on the acacia honey sample before the detecting by the ELSD through the HPLC is conducted; wherein the pretreatment comprises: dissolving the acacia honey sample in water, and conducting filtration.

13. The identification method of maturity of acacia honey according to claim 12, wherein water with a volume 3 to 5 times a mass of the acacia honey sample is added to obtain an acacia honey sample solution.

14. The identification method of maturity of acacia honey according to claim 7, wherein a process of detecting the acacia honey sample comprises: detecting the acacia honey sample by the ELSD through the HPLC; plotting a standard curve by a linear relationship between the turanose content and a peak area; according to the standard curve and an obtained peak area of the turanose detected in the acacia honey sample, calculating an turanose content; wherein the turanose content is a mass percentage relative to the acacia honey sample.

15. The identification method of maturity of acacia honey according to claim 11, wherein a process of detecting the acacia honey sample comprises: detecting the acacia honey sample by the ELSD through the HPLC; plotting a standard curve by a linear relationship between the turanose content and a peak area; according to the standard curve and an obtained peak area of the turanose detected in the acacia honey sample, calculating an turanose content; wherein the turanose content is a mass percentage relative to the acacia honey sample.

16. The identification method of maturity of acacia honey according to claim 12, wherein a process of detecting the acacia honey sample comprises: detecting the acacia honey sample by the ELSD through the HPLC; plotting a standard curve by a linear relationship between the turanose content and a peak area; according to the standard curve and an obtained peak area of the turanose detected in the acacia honey sample, calculating an turanose content; wherein the turanose content is a mass percentage relative to the acacia honey sample.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 shows a chromatogram of acacia honey with different maturities in Example 1 of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following examples are intended to illustrate the present disclosure, but not to limit the scope of the present disclosure.

[0033] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. The materials, reagents, and the like used in the examples are all commercially available, unless otherwise specified. Some of the instruments and reagents include: HPLC-based ELSD, Agilent Technologies, USA; electronic analytical balance (PL203), METTLERTOLEDO, Germany; ultrapure water machine (Milli-Q Gradient), Millipore, USA; vortex instrument (G560E), Scientific Industries, USE.

Example 1 Content Detection of Turanose in Acacia Honey of Different Maturities

[0034] 1. Source of samples: in 2019, 2020, and 2021, samples of acacia honey were collected from different bee farms in Yan'an, Shaanxi and Sanmenxia, Henan (the main production area of acacia honey), which were brewed by bees for 1 d, 3 d, 5 d, 7 d, 9 d, 11 d, and 13 d. For the samples of different brewing days, 3 samples were taken from each bee farm, and the brewing time and honeycomb sealing were recorded. All samples collected from 1 d to 5 d were manually concentrated to control their moisture content at 18% to 21%. The samples collected from 7 d to 13 d needed to measure moisture content, and the moisture content should be no more than 21%, and the honeycomb sealing needed to be no less than 75%.

[0035] The specific information of acacia honey samples was shown in Table 1 and Table 2. All acacia honey samples were tested for routine quality indicators and pollen identification, and the results showed that all samples were consistent with the attributes of the corresponding acacia honey.

[0036] All collected acacia honey samples were tested for turanose content.

[0037] 2. Sample pretreatment: 1 g of the acacia honey sample was added with 3 mL of ultrapure water, vortexed, balanced to 5 mL, filtered with a 0.22 ?m nylon filter membrane, and injected.

[0038] 3. Instrument condition setting:

[0039] (1) LC conditions: [0040] chromatographic column: Agilent Hi-Plex Pb, USP L19, 4.0 mm?250 mm; [0041] column temperature: 70? C.; [0042] injection volume: 50 ?L; [0043] mobile phase: ultrapure water; [0044] elution conditions: isocratic elution; and [0045] flow rate: 0.6 mL/min.

[0046] (2) ELSD conditions: [0047] atomization temperature: 90? C.; [0048] evaporation temperature: 60? C.; [0049] carrier gas flow rate: 1.2 SLM; and [0050] collection time period: no collection at 0-9 min (to avoid interference from high levels of fructose and glucose in honey), and data collection is conducted at 9-15 min.

[0051] 4. Plotting of standard curve: standard substances of turanose with concentrations of 0.02%, 0.1%, 0.2%, 0.5%, 1.0%, 2.0%, and 5.0% were prepared, and the logarithm of a concentration value (10 was a base logarithm) and the logarithm of a response value were calculated to draw a standard curve.

[0052] 5. Detection of turanose content in acacia honey samples: a standard curve was plotted by a linear relationship between the turanose content and a peak area; according to the standard curve and an obtained peak area of the turanose detected in the acacia honey sample, a turanose content was calculated.

[0053] According to statistics, the contents of turanose in acacia honey samples with different maturities were shown in Table 1 and Table 2. According to the above detection results, the content of turanose in the acacia honey sample was no less than 0.5%, and it was determined that the sample was mature acacia honey. This was consistent with the actual sampling results and met the conditions for mature acacia honey, that is, the acacia honey should be brewed in the hive for at least 7 d, and showed honeycomb sealing of no less than 75%. The content of turanose in the acacia honey sample was less than 0.5% and no less than 0.3%, and it was determined that the sample was semi-mature acacia honey. This sample was brewed in the hive for more than 3 d but no more than 5 d, and showed honeycomb sealing of 30% to 70%. The content of turanose in the acacia honey sample was less than 0.3%, and it was determined that the sample was immature acacia honey (the sample of 1 d to 3 d, basically showing no honeycomb sealing).

[0054] The detection spectrum of acacia honey with different maturities was shown in FIG. 1.

TABLE-US-00001 TABLE 1 Turanose content (%) and honeycomb sealing (%) in acacia honey samples of different years and different days of mature in Yan'an, Shaanxi (where samples of 1 d to 13 d were randomly collected from bee farms in each of 3 different regions, 3 parts for each sample, 63 samples per year, and 189 samples for 3 years) 1 d 3 d 5 d 7 d 9 d 11 d 13 d Year n = 9 n = 9 n = 9 n = 9 n = 9 n = 9 n = 9 2019 Turanose: ?0.1% Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: honeycomb 0.15% ? 0.04% 0.44% ? 0.04% 0.56% ? 0.04% 0.68% ? 0.06% 0.83% ? 0.06% 1.04% ? 0.1% sealing: honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb None sealing: sealing: sealing: sealing: sealing: sealing: 8% 35% 79% 85% 95% 96% 2020 Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: 0.13% ? 0.02% 0.16% ? 0.03% 0.42% ? 0.03% 0.63% ? 0.08% 0.73% ? 0.07% 0.94% ? 0.10% 1.30% ? 0.23% honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb sealing: sealing: sealing: sealing: sealing: sealing: sealing: 3% 9% 44% 83% 86% 93% 96% 2021 Turanose: ?0.1% Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: honeycomb 0.21% ? 0.03% 0.37% ? 0.06% 0.72% ? 0.10% 0.81% ? 0.09% 1.03% ? 0.14% 1.21% ? 0.21% sealing: honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb None sealing: sealing: sealing: sealing: sealing: sealing: 10% 39% 78% 88% 95% 95%

TABLE-US-00002 TABLE 2 Turanose content (%) and honeycomb sealing (%) in acacia honey samples of different years and different days of mature in Sanmenxia acacia production area, Henan (where samples of 1 d to 13 d were randomly collected from bee farms in each of 3 different regions, 3 parts for each sample, 63 samples per year, and 189 samples for 3 years) 1 d 3 d 5 d 7 d 9 d 11 d 13 d Year n = 9 n = 9 n = 9 n = 9 n = 9 n = 9 n = 9 2019 Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: 0.16% ? 0.05% 0.23% ? 0.04% 0.39% ? 0.06% 0.63% ? 0.06% 0.73% ? 0.07% 0.79% ? 0.06% 0.99% ? 0.1% honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb sealing: sealing: sealing: sealing: sealing: sealing: sealing: 6% 10% 54% 80% 85% 90% 92% 2020 Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: 0.20% ? 0.07% 0.25% ? 0.03% 0.41% ? 0.05% 0.70% ? 0.08% 0.86% ? 0.08% 0.94% ? 0.10% 1.13% ? 0.15% honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb sealing: sealing: sealing: sealing: sealing: sealing: sealing: 7% 10% 65% 77% 88% 92% 93% 2021 Turanose: ?0.1% Turanose: Turanose: Turanose: Turanose: Turanose: Turanose: honeycomb 0.16% ? 0.03% 0.36% ? 0.04% 0.62% ? 0.04% 0.77% ? 0.07% 0.90% ? 0.10% 0.96% ? 0.11% sealing: honeycomb honeycomb honeycomb honeycomb honeycomb honeycomb None sealing: sealing: sealing: sealing: sealing: sealing: 9% 68% 79% 80% 82% 83%

Example 2 Turanose as a Characteristic Marker in Identification of Commercially Available Acacia Honey

1. Source of Samples

[0055] A total of 18 honey samples of various grades or brands labeled as acacia honey were purchased from the market, and all samples were tested for pollen to prove that they were acacia honey.

[0056] 2. Sample pretreatment: 1 g of the acacia honey sample to be identified was added with 3 mL of ultrapure water, vortexed, balanced to 5.0 mL, filtered with a 0.22 ?m nylon filter membrane, and injected.

[0057] 3. Instrument condition setting:

[0058] (1) LC conditions: [0059] chromatographic column: Agilent Hi-Plex Pb, USP L19, 4.0 mm?250 mm; [0060] column temperature: 70? C.; [0061] injection volume: 50 ?L; [0062] mobile phase: ultrapure water; [0063] elution conditions: isocratic elution; and [0064] flow rate: 0.6 mL/min.

[0065] (2) ELSD conditions: [0066] atomization temperature: 90? C.; [0067] evaporation temperature: 60? C.; [0068] carrier gas flow rate: 1.2 SLM.

[0069] 4. Plotting of standard curve: standard substances of turanose with concentrations of 0.02%, 0.1%, 0.2%, 0.5%, 1.0%, 2.0%, and 5.0% were prepared, and the logarithm of a concentration value (10 was a base logarithm) and the logarithm of a response value were calculated to draw a standard curve.

[0070] 5. Detection of turanose content in acacia honey samples: a standard curve was plotted by a linear relationship between the turanose content and a peak area; according to the standard curve and an obtained peak area of the turanose detected in the acacia honey sample, a turanose content was calculated.

[0071] The results were shown in Table 3.

TABLE-US-00003 TABLE 3 Determination of turanose content in acacia honey sampled in the market Sample Turanose content No. (%) 1 0.45 2 0.16 3 <0.1% 4 <0.1% 5 <0.1% 6 <0.1% 7 0.55 8 <0.1% 9 0.63 10 0.35 11 0.43 12 0.87 13 0.64 14 0.36 15 0.73 16 1.21 17 0.23 18 0.76

[0072] The results showed that the 7 samples had a turanose content of greater than 0.5%, and were determined as mature acacia honey. According to the sample traceability information, it was confirmed that the samples came from certified enterprises producing mature acacia honey. This indicated that the identification method of maturity provided by the present disclosure showed a high discrimination accuracy. For other samples, 4 samples had a turanose content between 0.3 to 0.5%, and were determined as semi-mature acacia honey; 7 samples had a turanose content of less than 0.3%, and were determined as immature acacia honey. The above results proved that the identification method of the present disclosure could effectively identify the maturity of acacia honey. Therefore, the method can be used for grading the maturity of commercial acacia honey, so as to realize different pricing of acacia honey according to the maturity.

[0073] Although the present disclosure has been described in detail above with general description and specific embodiments, some modifications or improvements can be made on the basis of the present disclosure, which will be apparent to those skilled in the art. Therefore, all of these modifications or improvements made without departing from the spirit of the present disclosure fall within the claimed scope of the present disclosure.