Method for improving sensory cleanliness of Maotai-flavor liquor

Abstract

The invention discloses a method for improving sensory cleanliness of Maotai-flavor baijiu in the technical field of baijiu brewing, the Maotai-flavor baijiu is treated by using kettle type distillation equipment, and the distillation time of foreign flavor components such as dimethyl disulfide, dimethyl trisulfide and 2, 3-butanedione is different from that of key aroma substance components by adjusting the feeding alcoholic strength and heating parameters, so that the taste of the maotai-flavor baijiu is improved, and the taste of the maotai-flavor baijiu is improved. The optimal distillate collection time is determined through experiments, and finally the Maotai-flavor liquor with improved cleanliness is obtained. The method is simple and convenient to operate, time-saving and labor-saving, and can be used for effectively removing the components with different flavors, namely dimethyl trisulfide, dimethyl disulfide and 2, 3-butanedione, in the Maotai-flavor liquor, so that the sensory cleanliness of the liquor body is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of Baijiu brewing, and particularly relates to a method for improving the sensory cleanliness of Maotai-flavor Baijiu. Background Art

[0002] Currently, the techniques for controlling off-flavor substances in the production of Maotai-flavor Baijiu mainly include raw material screening, fermentation process optimization, and addition of adsorbents. For example, by carefully selecting sorghum and controlling the koji-making temperature, the generation of off-flavor precursor substances can be reduced; using activated carbon adsorption or ion exchange resin treatment can partially remove off-flavor components. In addition, the dilution distillation technique changes the rectification coefficient by reducing the alcohol content, and has a certain effect on removing volatile off-flavor substances. However, these techniques have limited effects on specifically removing salted vegetable flavor (dimethyl disulfide, dimethyl trisulfide) and sour smell substances (2,3-butanedione) and improving the sensory cleanliness of the liquor body, and are prone to introducing foreign impurities or causing loss of aroma components.

[0003] The core defects of the existing technology are as follows: The improvement effect of raw material screening and process optimization on the off-flavors of the finished liquor is limited; the use of adsorbents easily affects the flavor of the liquor body; the traditional dilution distillation has not systematically studied the synergistic regulation effect of alcohol content and heating parameters on the distillation time of target off-flavor substances (such as dimethyl trisulfide, dimethyl disulfide, 2,3-butanedione), resulting in low removal efficiency and difficulty in retaining key aroma components. For example, the distillation ranges of dimethyl trisulfide (boiling point 113 - 114°C) overlap with those of some high-boiling aroma substances, and it is difficult for the traditional process to accurately separate them, making it impossible to effectively improve the sensory cleanliness of the liquor body. Summary of the Invention

[0004] The present invention aims to provide a method for improving the sensory cleanliness of Maotai-flavor Baijiu to solve the technical problem of low efficiency in removing off-flavor substances in the production of traditional Maotai-flavor Baijiu.

[0005] To solve the above technical problems, the present invention provides the following technical solution: A method for improving the sensory cleanliness of Maotai-flavor Baijiu, comprising the following steps:

[0006] S1. Dilute the Maotai-flavor Baijiu to an alcohol content of 35 - 40% vol to obtain a diluted liquor sample;

[0007] S2. Add the diluted liquor sample into a pot still, set the heating temperature to 80 - 120°C, and turn on 1 - 2 heating rods for heating and distillation;

[0008] S3. After the base liquor in the pot still starts to boil, adjust the cooling water flow rate and collect the distilled liquor;

[0009] S4. Stop taking the liquor when the alcohol content is lower than 5% vol, and turn off the distillation equipment;

[0010] S5. Collect the distillate liquor in the distillation range of 9 to 42 minutes, and after merging, a Maotai-flavor liquor with improved sensory cleanliness is obtained.

[0011] Furthermore, the alcohol content of the diluted liquor sample in step S1 is preferably 37.5% vol.

[0012] Furthermore, the heating temperature in step S2 is preferably 100 °C, and only 1 heating rod is turned on.

[0013] Furthermore, the initial opening degree of the cooling water of the pot still in step S3 is 1 / 2, and it is fully opened after boiling.

[0014] Furthermore, the alcohol content of the distillate liquor in the distillation range of 9 to 42 minutes collected in step S5 is 50% vol to 80% vol.

[0015] Furthermore, a Maotai-flavor liquor prepared by the method according to any one of the above, wherein the content of dimethyl trisulfide is ≤ 70 μg / L, the content of dimethyl disulfide is ≤ 100 μg / L, and the content of 2,3-butanedione is ≤ 5 mg / L.

[0016] Advantages of the present invention:

[0017] 1. The present invention uses a pot still. By finely adjusting the heating parameters, dilution alcohol content and distilling time, the efficient removal of dimethyl trisulfide, dimethyl disulfide and 2,3-butanedione in Maotai-flavor liquor is achieved. Experimental data shows that after optimization, the content of dimethyl trisulfide in the liquor sample is reduced to below 70 μg / L, the content of dimethyl disulfide is reduced to below 100 μg / L, the content of 2,3-butanedione is reduced to below 5 mg / L, and the foreign and off-flavor substances are significantly reduced, effectively improving the sensory quality of Maotai-flavor liquor.

[0018] 2. Compared with traditional methods such as physical adsorption, chemical treatment and biodegradation, the distillation technology adopted in the present invention does not need to introduce additional reagents, has simple operation, large treatment capacity and remarkable effect, and is suitable for large-scale industrial production. At the same time, by reasonably setting the distillation parameters, the method of the present invention can process a large number of liquor samples in a short time, significantly improving the production efficiency.

[0019] 3. While removing foreign and off-flavor substances, the present invention maximally retains the original flavor substances of Maotai-flavor liquor. During the distillation process, by precisely controlling the heating temperature and distilling time, the destruction of the liquor body flavor by high temperature is avoided, ensuring that the processed Maotai-flavor liquor has a pure taste and does not introduce any foreign impurities.

[0020] 4. The method of the present invention is not only applicable to Maotai-flavor liquor, but can also be widely promoted and applied to Chinese liquors such as light-flavor and strong-flavor liquors, as well as various types of international spirits such as whisky and vodka, having extremely high promotion value and application prospects. Detailed implementation manners

[0021] The following is a further detailed description through specific implementation manners:

[0022] Example:

[0023] A method for improving the sensory cleanliness of Maotai-flavor liquor, comprising the following steps:

[0024] Take Maotai-flavor liquor and add softened water to dilute it. Dilute its alcohol content to 37.5% vol. Transfer all the samples into a commercially available pot still, tighten the lid of the still, turn on half of the cooling water, turn on 1 heating rod of the pot still, set the heating temperature to 100 °C, and start heating and distilling. When the base liquor in the pot starts to boil, turn on all the cooling water, start collecting the liquor immediately after the liquor comes out, and stop collecting the liquor when the alcohol content is lower than 5% vol. Turn off the pot still instrument. The liquor collection time for each distillation section and the corresponding alcohol content are shown in Table 1. The optimal liquor collection reference time is 9 - 42 min (distillation section 3 - 6), and the alcohol content is 50% vol - 80% vol.

[0025] Table 1 Liquor collection time and alcohol content corresponding to different distillation sections

[0026] Fraction Time Alcohol content (% vol) Feed sample / 35～40 Fraction 1 0 - 2 min 70～80 Fraction 2 2 - 9 min 70～80 Fraction 3 9 - 18 min 65～80 Fraction 4 18 - 27 min 65～80 Fraction 5 27 - 33 min 60～75 Fraction 6 33 - 42 min 50～60 Fraction 7 42 - 57 min 20～50 Fraction 8 57 - 63 min 1～10

[0027] An operating method condition parameter for removing hetero-flavor components (dimethyl trisulfide, dimethyl disulfide, 2,3-butanedione) and improving the cleanliness of Maotai-flavor liquor includes:

[0028] (1) The alcohol content of the charged liquor sample is 35 - 40% vol;

[0029] (2) Set the heating temperature to 80 - 120 °C, and the number of heating rods is 1 - 2;

[0030] (3) The reference time for liquor distillation is 0 - 63 min, and the alcohol content is 2% vol - 80% vol;

[0031] (4) Based on the above conditions (1) - (3), the optimal charged liquor alcohol content is 37.5% vol; the optimal heating parameters are 100 °C and 1 heating rod; the optimal distillation section collection time is 9 - 42 min (distillation section 3 - 6), the alcohol content is 50% vol - 80% vol, and the alcohol recovery rate is 87.49% - 93.85%.

[0032] The determination standards for dimethyl disulfide, dimethyl trisulfide, and 2,3-butanedione are as follows:

[0033] 1. Based on headspace solid-phase microextraction combined with gas chromatography - mass spectrometry, determine the contents of dimethyl trisulfide and dimethyl disulfide in the hetero-flavor liquor before and after optimization

[0034] 1.1 Sample pretreatment

[0035] Preparation of internal standard solution: Weigh 10 mg of diisopropyl disulfide standard into a 100 mL volumetric flask, and make up the volume to the mark with ethanol (chromatographically pure) to obtain the internal standard stock solution; accurately measure 100 μL of the internal standard stock solution into a 100 mL volumetric flask, and make up the volume to the mark with ethanol (chromatographically pure) to obtain the internal standard solution.

[0036] Preparation of test sample: Take 1.5 g of sodium chloride and 4 mL of water and place them in a 20 mL headspace vial. Then add 1 mL of the sample and 10 μL of the internal standard solution. After headspace solid-phase microextraction, it is used for GC-MS analysis.

[0037] 1.2 Detection conditions

[0038] Headspace solid-phase microextraction conditions: Sample heating time 10 min, heating oven temperature 50 °C, GC cycle time 35 min, sample extraction time 20 min, sample desorption time 5 min, shaking speed 250 rpm.

[0039] GC-MS detection conditions: Solvent delay 6 min. The inlet temperature of the gas chromatograph is 250 °C, the column flow rate is 1.5 mL / min, and the split ratio is 10:1; Temperature programming: Initial temperature 50 °C, hold for 2 min, increase to 90 °C at a rate of 10 °C / min, hold for 1 min, increase to 130 °C at a rate of 5 °C / min, do not hold, increase to 180 °C at a rate of 20 °C / min, and hold for 10 min.

[0040] The mass spectrometry ion source is an EI source, the ion source temperature is 230 °C, the mass spectrometry transfer line temperature is 250 °C, and the quadrupole temperature is 150 °C. Selective ion monitoring (SIM) mode is used.

[0041] 1.3 Quantitative analysis

[0042] Calculation is carried out by the internal standard method. With the ratio (x) of the concentration of each component in the standard solution to the concentration of the internal standard as the abscissa and the ratio (y) of the peak area of each component to the peak area of the internal standard as the ordinate, a standard curve is plotted, and the concentrations of dimethyl disulfide and dimethyl trisulfide in the off-flavor wine are obtained according to the standard curve.

[0043] 1.4 Calculation of the change rate of dimethyl trisulfide and dimethyl disulfide

[0044] Calculate the change rate of dimethyl trisulfide and dimethyl disulfide in the Maotai-flavor liquor after treatment. The calculation formula is as follows:

[0045]

[0046] When the obtained change rate of dimethyl trisulfide and dimethyl disulfide is "positive", it is the "increase rate"; when the obtained change rate of dimethyl trisulfide and dimethyl disulfide is "negative", it is the "decrease rate".

[0047] 2. Determine the content of 2,3-butanedione in the heteroflavored wine before and after optimization by gas chromatography-mass spectrometry

[0048] 2.1 Sample pretreatment

[0049] Shake the wine sample well and place it in a ground glass bottle for later use. Take an appropriate amount of the sample, filter it through a 0.22 μm organic filter membrane, and place it in an injection vial for GC analysis.

[0050] 2.2 Detection conditions

[0051] GC conditions: Use an HP-FFAP chromatographic column (50 m × 0.2 mm, 0.33 μm, model: 19091F-105); the inlet temperature is 200 °C, and the detector temperature is 220 °C; the programmed temperature rise is an initial column temperature of 40 °C, held for 2 min, heated at 3 °C / min to 90 °C, and then heated at 15 °C / min to 230 °C, held for 20 min; the carrier gas is high-purity nitrogen (purity > 99.999%), the flow control mode is a constant flow mode, and the flow rate is 1 mL / min; the injection method is split injection, and the split ratio is 1:20; the injection volume is 1 μL.

[0052] 2.3 Qualitative and quantitative analysis

[0053] Use the retention time of the 2,3-butanedione standard product to qualitatively analyze the target substance. After processing the 2,3-butanedione working solutions with different concentrations according to the above sample treatment method, perform instrumental analysis. Draw a standard curve with the peak area of 2,3-butanedione as the vertical coordinate and the concentration as the horizontal coordinate for quantitative analysis.

[0054] 2.4 Calculation of the change rate of 2,3-butanedione

[0055] Calculate the change rate of 2,3-butanedione in the optimized Jiangxiang-type Baijiu. The calculation formula is as follows:

[0056]

[0057] When the obtained change rate of 2,3-butanedione is a "positive number", it is the "increase rate"; when the obtained change rate of 2,3-butanedione is a "negative number", it is the "decrease rate".

[0058] 3. Optimization experiment

[0059] Experiment 1: Optimize the pot still equipment for Jiangxiang-type Baijiu (the alcohol content of the charged wine is 35% vol, 37.5% vol, 40% vol), determine the contents of dimethyl trisulfide, dimethyl disulfide, and 2,3-butanedione, and select the optimal alcohol content of the charged wine and the optimal distillation time period based on the decline rates of each component.

[0060] The Maotai-flavor Baijiu is respectively diluted to 37.5% vol, 40% vol, and 35% vol for feeding, and optimized treatment is carried out. The results of the substance contents before and after optimization are shown in Table 2.

[0061] Table 2 Differences in Substance Contents of Maotai-flavor Baijiu with Different Dilution Degrees before and after Distillation Optimization

[0062]

[0063]

[0064] Note: The substance contents have been uniformly converted to 53% vol.

[0065] It can be seen from Table 2 that:

[0066] (1) For the 37.5% vol sample in the distillation sections 3 - 7 (9 - 57 min), the decline rate of 2,3-butanedione is 3.21% - 100%, the decline rate of dimethyl disulfide is 20.5% - 100%; the decline rate of dimethyl trisulfide is 34.07% - 51.14%.

[0067] (2) For the 40% vol sample in the distillation sections 3 - 7 (9 - 57 min), the change rate of 2,3-butanedione is -100% - 8.37%, the change rate of dimethyl disulfide is -87.99% - 8.85%; the decline rate of dimethyl trisulfide is 28.86% - 52.11%.

[0068] (3) For the 35% vol sample in the distillation sections 3 - 7 (9 - 57 min), the decline rate of 2,3-butanedione is 0.73% - 100%, the decline rate of dimethyl disulfide is 24.53% - 100%; the decline rate of dimethyl trisulfide is 40.12% - 50.18%.

[0069] (4) In the distillation sections 1 - 2 (0 - 9 min) and section 8 (57 - 63 min), the contents of 2,3-butanedione, dimethyl disulfide, and dimethyl trisulfide in the samples with the alcohol content of the feeding Baijiu being 35% vol - 40% vol are 30% - 200% higher than those of the samples before distillation.

[0070] In summary, for Jiangxiang-flavor Baijiu distilled using an optimized pot still (with the initial alcohol content of the charged liquor being 35% vol - 40% vol), the contents of off-flavor components (dimethyl disulfide, dimethyl trisulfide, 2,3-butanedione) in distillate segments 1 - 2 (0 - 9 min) and segment 8 (57 - 63 min) are 30% - 200% higher than those in the original sample, effectively enriching the off-flavor components; the change rates of off-flavor components (dimethyl disulfide, dimethyl trisulfide, 2,3-butanedione) in distillate segments 3 - 7 are -100% - 8.85%, effectively removing dimethyl trisulfide, dimethyl disulfide, and 2,3-butanedione. The removal effects at different initial alcohol contents of the charged liquor are as follows: 37.5% vol > 35% vol > 40% vol. Therefore, the optimal distillation time is distillate segments 3 - 7 (9 - 57 min), and the optimal initial alcohol content of the charged liquor is 37.5% vol.

[0071] Experiment 2: Jiangxiang-flavor Baijiu was distilled using an optimized pot still (at 100 °C, with 1 - 2 heating rods turned on), and the contents of dimethyl trisulfide, dimethyl disulfide, and 2,3-butanedione were measured. Based on the decline rates of each component, the optimal heating parameters were selected.

[0072] Jiangxiang-flavor Baijiu was diluted to 37.5% vol for feeding, with 1 - 2 heating rods turned on. The results of the substance contents before and after optimization are shown in Table 3.

[0073] Table 3 Differences in Substance Contents before and after Optimization with Different Heating Parameters

[0074]

[0075]

[0076] Note: The substance contents have been uniformly converted to 53% vol.

[0077] As can be seen from Table 3:

[0078] (1) For two heating rods, in distillate segments 3 - 7 (9 - 57 min), the decline rate of 2,3-butanedione is 3.21% - 100%, the decline rate of dimethyl disulfide is 20.5% - 100%, and the decline rate of dimethyl trisulfide is 34.07% - 51.14%.

[0079] (2) For one heating rod, in distillate segments 3 - 7 (9 - 57 min), the change rate of 2,3-butanedione is -100% - 33.63%, the decline rate of dimethyl disulfide is 91.42% - 100%, and the change rate of dimethyl trisulfide is 63.72% - 86.47%.

[0080] In summary, after the optimization of the pot still equipment for Jiangxiang-flavor Baijiu (turning on 1 - 2 heating rods), the change rates of the abnormal and off-flavor components (dimethyl disulfide, dimethyl trisulfide, 2,3-butanedione) in the distillation segments 3 - 7 are -100% to 33.63%, which can effectively remove dimethyl trisulfide, dimethyl disulfide, and 2,3-butanedione. Considering the comprehensive energy consumption and the sensory results after optimization, the decline rate is higher with two heating rods, but the sensory results are not good. It is recommended that the optimal heating parameters be: 100°C, using a single heating rod.

[0081] Experiment 3: After the optimization of the pot still equipment for Jiangxiang-flavor Baijiu, under the optimal alcohol content (37.5% vol) and the optimal heating parameters (100°C, single heating rod), the removal effects of dimethyl trisulfide, dimethyl disulfide, and 2,3-butanedione in different liquor-taking distillation segments and the sensory evaluation results.

[0082] Taking typical abnormal and off-flavor liquors A, B, and C as experimental samples, diluting them to 37.5% vol for feeding, and using a single heating rod as the heat source. Collect and mix the distillation segments (distillation segments 3 - 7, 9 - 57 min) with the content of abnormal and off-flavor components (dimethyl disulfide, dimethyl trisulfide, 2,3-butanedione) lower than the original samples. Since the tail liquor flavor in distillation segment 7 (42 - 57 min) is strong and affects the product quality, it is preferred to mix distillation segments 3 - 6 (9 - 42 min). The sensory evaluation results are shown in Table 4, and the material content results before and after optimization are shown in Table 5.

[0083] Table 4 Sensory evaluation results of typical abnormal and off-flavor samples before and after optimization

[0084]

[0085] Table 5 Differences in material content of typical abnormal and off-flavor samples before and after optimization

[0086]

[0087] Note: The material content has been uniformly converted to 53% vol.

[0088] As can be seen from Table 4 and Table 5:

[0089] (1) Before optimization, samples A, B, and C belonged to typical abnormal and off-flavor Baijiu. After optimization, none of the samples had obvious abnormal and off-flavor (rancid smell, pickled vegetable smell), and the cleanliness of the liquor body was significantly improved.

[0090] (2) For samples A, B, and C in the distillation segments 3 - 6 (9 - 42 min), the decline rate of dimethyl disulfide is 91.42% - 100%, and the decline rate of dimethyl trisulfide is 29.03 - 86.26%; the change rate of the rancid smell substance (2,3-butanedione) is -100% to 33.63%.

[0091] (3) The alcohol recovery rate of this method is 87.49% - 93.85%, meeting the production recovery rate requirements.

[0092] In summary, after the optimization of the pot still for typical off-flavor liquor, the change rates of off-flavor components (dimethyl disulfide, dimethyl trisulfide, 2,3-butanedione) in distillation sections 3 - 6 (9 - 42 min) are -100% - 33.63%, and the alcohol recovery rates are 87.49% - 93.85%. The sensory results show that the cleanliness of the optimized sample (the mixture of distillates in sections 3 - 6) is significantly improved. This method can effectively remove the off-flavor components (dimethyl disulfide, dimethyl trisulfide, 2,3-butanedione) in the sample and significantly improve the cleanliness of the liquor body.

[0093] Advantages of the present invention

[0094] Economic benefits: This method has the advantages of being simple and easy to operate, having a large amount of optimization, not introducing impurities, with stable production and significant economic benefits. Using the method disclosed in this patent to optimize Maotai-flavor liquor can effectively reduce the content of off-flavor components (dimethyl trisulfide, dimethyl disulfide, 2,3-butanedione) in the liquor, improve the cleanliness of the liquor body, and improve the off-flavor of the liquor.

[0095] Social benefits: This patent provides a practical method for removing off-flavor components (dimethyl trisulfide, dimethyl disulfide, 2,3-butanedione) in Maotai-flavor liquor, which can be used for reference in the optimization of off-flavor liquor in various liquor industries to improve economic benefits.

[0096] The above are only the embodiments of the present invention. Common knowledge such as specific structures and characteristics known in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to interpret the content of the claims.

Claims

1. A method for improving the sensory cleanliness of Maotai-flavor liquor, characterized in that, It includes the following steps: S1. Dilute the Maotai-flavor liquor to an alcohol content of 35-40% vol to obtain a diluted liquor sample; S2. Add the diluted liquor sample into a pot still, set the heating temperature at 80-120°C, and turn on 1-2 heating rods to carry out heating and distillation; S3. After the base liquor in the pot still starts to boil, adjust the cooling water flow rate and collect the distilled liquor; S4. Stop liquor taking when the alcohol content is lower than 5% vol, and turn off the distillation equipment; S5. Collect the distillate liquor in the distillation section with a distillation time of 9 minutes to 42 minutes, and after merging, obtain the Maotai-flavor liquor with improved sensory cleanliness.

2. The method for improving the sensory cleanliness of Maotai-flavor liquor according to claim 1, characterized in that: In step S1, the alcohol content of the diluted liquor sample is preferably 37.5% vol.

3. A method for improving the sensory cleanliness of Maotai-flavor liquor according to claim 2, characterized in that: In step S2, the heating temperature is preferably 100°C, and only 1 heating rod is turned on.

4. A method for improving the sensory cleanliness of Maotai-flavor liquor according to claim 3, characterized in that: In step S3, the initial opening degree of the cooling water of the pot still is 1 / 2, and it is fully opened after boiling.

5. A method for improving the sensory cleanliness of Maotai-flavor liquor according to claim 4, characterized in that: In step S5, the alcohol content of the distillate liquor in the distillation section with a distillation time of 9 minutes to 42 minutes is 50% vol to 80% vol.

6. A Maotai-flavor Chinese liquor, characterized in that: The Maotai-flavor liquor is prepared by the method according to any one of claims 1-5, wherein the content of dimethyl trisulfide is ≤70 μg / L, the content of dimethyl disulfide is ≤100 μg / L, and the content of 2,3-butanedione is ≤5 mg / L.

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