Method for controlling the odor of distiller's grains and application thereof

Abstract

The application discloses a method for controlling the odor of distiller's grains in liquor and application thereof, and comprises the following steps: firstly, subjecting the liquor to be treated to electromagnetic field treatment, and then subjecting the liquor to dynamic adsorption treatment by using activated macroporous resin, so as to obtain liquor with removed odor of distiller's grains; the electromagnetic field technology is used to oxidize the polar molecules in the liquor under the action of a strong magnetic field, so as to control the odor of distiller's grains in the liquor. According to the application, the odor of distiller's grains in the liquor is effectively controlled, meanwhile, the physicochemical properties and overall flavor of the liquor do not change significantly, the odor and irritancy of the typical liquor with odor of distiller's grains are obviously reduced, the loss rate of total acid is less than 7%, the loss rate of total ester is less than 7%, the retention rate of important ester substances is more than 85%, the retention rate of important alcohol substances is more than 85%, the retention rate of important aldehyde substances is more than 75%, and the removal rate of key odor substances of distiller's grains is more than 85%.

Description

Technical Field

[0001] This invention relates to the field of liquor processing technology, and in particular to a method and application for controlling the offal flavor in liquor. Background Technology

[0002] Baijiu, a unique alcoholic beverage in China, boasts a distinctive brewing process and a complex and diverse range of flavor profiles. Aroma is a key indicator of baijiu quality, and the complex brewing process and unique fermentation environment can cause the resulting liquor to deviate from its expected flavor. Examples include odors resembling bran, earthy soil, yellow water, salted vegetables, inferior koji (fermented starter culture), moldy soil, oil, and lees. Excessive lees in baijiu can disrupt its balance, leading to a poor consumer experience. Their presence also lowers product quality, reducing consumer purchasing desire and consequently causing economic losses for businesses and hindering industry development. Therefore, exploring lees control techniques in baijiu is of great significance for the further development of the baijiu industry.

[0003] Some studies have suggested optimizing the production process of baijiu to reduce off-flavors and improve its overall quality. However, this method can only prevent the production of baijiu with off-flavors and is ineffective for baijiu that already has a strong musty smell. Furthermore, changing the production process will inevitably alter the overall flavor of the baijiu, which does not meet the intended purpose.

[0004] Post-processing techniques are commonly used to control off-flavors or improve the quality of baijiu (Chinese white liquor). These techniques include adsorption, oxidation, membrane filtration, and double distillation. Adsorption is simple to operate and inexpensive, making it the most widely used method in post-processing. Macroporous resins utilize their abundant pores for physical adsorption; weakly basic, strongly basic, and strongly acidic resins are macroporous ion exchange resins that combine adsorption and ion exchange functions. However, these adsorbents lack specificity for removing off-flavors and may not be effective in removing the musty taste from baijiu. Summary of the Invention

[0005] To address the aforementioned problems in existing technologies, this invention provides a method and application for controlling the musty flavor in baijiu (Chinese liquor). This invention utilizes electromagnetic field technology to weaken the polar bond energy of polar molecules within the liquor under the influence of a strong magnetic field, thus facilitating their movement and promoting various reactions and the directional arrangement of molecules. Furthermore, the strong magnetic field enhances oxidation in the liquor, achieving a more targeted control of the musty flavor. While effectively controlling the musty flavor in baijiu, this invention does not significantly alter the physicochemical properties and overall flavor of the baijiu.

[0006] The technical solution of the present invention is as follows:

[0007] The first objective of this invention is to provide a method for controlling the offal flavor in baijiu (Chinese liquor), the method comprising the following steps:

[0008] The liquor to be treated is first subjected to electromagnetic field treatment, and then subjected to dynamic adsorption treatment with activated macroporous resin to obtain liquor with removed lees flavor.

[0009] The conditions for electromagnetic field treatment are: frequency 10-100Hz, electric field strength 5-10kv / cm, and treatment time 10-60min.

[0010] In one embodiment of the present invention, the liquor is from a winery in Shaoxing and has an alcohol content of 49.2% vol.

[0011] In one embodiment of the present invention, the liquor to be processed has a strong fermented aroma.

[0012] In one embodiment of the present invention, the macroporous resin is a macroporous adsorption resin, a cation exchange resin, or an anion exchange resin.

[0013] In one embodiment of the present invention, the macroporous resin is one or more of D314, C151, D730, DM130, and XDA-1. Parameters for each type of resin are shown in Table 1.

[0014] Table 1

[0015] model type <![CDATA[Specific surface area (m 2 / g)]]> Particle size range (mm) Optimal pH D314 Anion exchange resin 20-40 0.45-0.70 1～7 C151 Cation exchange resin 20-40 0.40-0.70 1～14 D730 Anion exchange resin 20-40 0.45-0.70 1-14 DM130 Macroporous adsorption resin 500-550 0.30-1.25 4～10 XDA-1 Macroporous adsorption resin 1279 0.31-1.25 1-14

[0016] In one embodiment of the present invention, the method for activating the macroporous adsorption resin is as follows: soaking in anhydrous ethanol overnight, discarding the soaking solution, washing with anhydrous ethanol, and then repeatedly washing with ultrapure water until odorless, and filtering out for later use.

[0017] In one embodiment of the present invention, the method for activating the cation exchange resin or the anion exchange resin is as follows: the macroporous resin is soaked in anhydrous ethanol and then soaked alternately in alkali and acid.

[0018] In one embodiment of the present invention, the specific method for activating the cation exchange resin is as follows: First, the resin is soaked in anhydrous ethanol for 20-30 minutes, washed with ultrapure water, and then soaked alternately with 4-5 wt% sodium hydroxide solution and 4-5 wt% hydrochloric acid solution for 3-4 times, each time for 20-30 minutes. The last soaking is with hydrochloric acid solution. After washing with ultrapure water until neutral, the resin is filtered and set aside.

[0019] In one embodiment of the present invention, the specific method for activating the anion exchange resin is as follows: First, the resin is soaked in anhydrous ethanol for 20-30 minutes, washed with ultrapure water, and then soaked alternately with 4-5 wt% sodium hydroxide solution and 4-5 wt% hydrochloric acid solution for 3-4 times, each time for 20-30 minutes. The last soaking is with sodium hydroxide solution. After washing with ultrapure water until neutral, the resin is filtered and set aside.

[0020] In one embodiment of the present invention, during the dynamic adsorption process, activated macroporous resin is filled into an atmospheric pressure chromatography column with a column diameter ratio of 15-25.

[0021] In one embodiment of the present invention, during the dynamic adsorption process, the activated macroporous resin accounts for 70-90% of the column volume.

[0022] In one embodiment of the present invention, during the dynamic adsorption process, the sample loading amount is 6-10 BV.

[0023] In one embodiment of the present invention, during the dynamic adsorption process, the sample loading flow rate is 3-7 BV / h.

[0024] The second objective of this invention is to provide a method for controlling the lees flavor in baijiu (Chinese liquor) and its application in the baijiu processing process.

[0025] The beneficial technical effects of this invention are as follows:

[0026] Currently, six key lees-like substances have been identified in baijiu with a strong lees flavor: 2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and terbinafine. These substances mostly contain hydroxyl and carbonyl groups. Electromagnetic field technology can weaken the polar bond energy of polar molecules in baijiu under the influence of a strong magnetic field, thus facilitating their movement and promoting various reactions and the directional arrangement of molecules. Furthermore, the oxidation process in baijiu is enhanced under a strong magnetic field.

[0027] This invention, after selecting the adsorbent and processing the wine sample, simultaneously considers the control effect of off-flavors, physicochemical indicators, aroma changes, and the retention effect of important flavors, so as to ensure that the original flavor of the wine sample can be well preserved.

[0028] This invention employs electromagnetic field treatment technology and macroporous resin adsorption technology to treat baijiu (Chinese liquor), and combines the two technologies to measure changes in aroma properties such as lees flavor and irritation, changes in physicochemical indicators, changes in important flavor substances (OAV>1), and removal of key lees flavor substances before and after treatment. The results show that the lees flavor in baijiu is effectively controlled, the irritation is reduced, the changes in physicochemical properties are small, the loss of important flavor substances is small, and the removal rate of key lees flavor substances is high.

[0029] This invention significantly reduces the lees flavor and irritation in typical fermented baijiu, with a total acid loss rate of <7%, a total ester loss rate of <7%, a retention rate of >85% for important esters, a retention rate of >85% for important alcohols, a retention rate of >75% for important aldehydes, and a removal rate of >85% for key lees flavor substances.

[0030] The method of this invention significantly reduced the lees flavor in the liquor (P < 0.001), by 60.53%; and significantly reduced the irritation (P < 0.01), by 62.50%. Attached Figure Description

[0031] Figure 1 The following are examples of changes in aroma properties before and after treatment in the embodiments and comparative examples of the present invention. Detailed Implementation

[0032] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] Alcohol content testing: conducted according to GB 5009.225—2016 "Determination of Ethanol Concentration in Wine - Alcohol Meter Method"; Total acid and total ester testing: conducted according to GB / T 10345—2022 "Analytical Methods for Baijiu".

[0034] Sensory evaluation method: 20 professionally trained sensory evaluators were selected to conduct sensory evaluations of seven indicators of the baijiu (Chinese liquor) according to a predefined scheme, including fruit aroma, floral aroma, grassy aroma, grain aroma, almond aroma, fermented flavor and irritation, and to score the intensity of the flavors. The scoring range was 0 (very weak) to 5 (very strong).

[0035] Flavor compound detection: Qualitative and quantitative analysis was performed according to previously reported methods, with important flavor compounds being those with OAV>1.

[0036] Loss rate calculation: Loss rate = (Concentration of analyte before adsorption - Concentration of analyte after adsorption equilibrium) / Concentration of analyte before adsorption × 100%

[0037] Aroma change calculation: Percentage change = (Aroma score of analyte before adsorption - Aroma score of analyte after adsorption equilibrium) / Aroma score of analyte before adsorption × 100%

[0038] Calculation of retention rate of important flavor compounds (OAV>1): Retention rate = (concentration of analyte before adsorption / concentration of analyte after adsorption equilibrium) × 100%.

[0039] Calculation of retention rates of 6 key substances with fermented odor (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and earth-flavoring agent): Removal rate = (Concentration of analyte before adsorption - Concentration of analyte after adsorption equilibrium) / Concentration of analyte before adsorption × 100%.

[0040] Comparative Example 1

[0041] Typical samples of fermented baijiu were treated with a magnetic field of 50 Hz and 5 kV / cm for 10, 20, 40, and 60 min, respectively. Physicochemical indicators, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and earth element) were calculated before and after treatment. The results are shown in Tables 2-5.

[0042] Comparative Example 2

[0043] Five macroporous resins—D314, C151, D730, DM130, and XDA-1—were selected to treat typical baijiu samples with a fermented, musty flavor. DM130 and XDA-1 resins were soaked in anhydrous ethanol overnight, the soaking solution was discarded, and after washing with anhydrous ethanol, they were repeatedly washed with ultrapure water until odorless, then filtered and set aside. The other three resins were first soaked in anhydrous ethanol for 20 minutes, washed with ultrapure water, and then soaked four times alternately with 5wt% sodium hydroxide solution and 5wt% hydrochloric acid solution, 20 minutes each time. C151 resin was soaked in hydrochloric acid solution for the last time, while D314 and D730 resins were soaked in sodium hydroxide solution for the last time. After washing with ultrapure water until neutral, they were filtered and set aside. 24g of pretreated macroporous resin was packed into columns (1.6cm×30cm) and used to treat 10BV of wine samples at a flow rate of 5BV / h. The eluent was collected, and the physicochemical properties, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key substances for fermented grain flavor (2-nonanol, trans-2-nonenal, n-decanol, trans-2,4-nonadienal, nonanal, and earth element) were calculated for the wine samples before and after adsorption treatment. The results are shown in Table 2-5.

[0044] Example 1

[0045] Typical samples of fermented baijiu were treated with an electromagnetic field of 50 Hz and 5 kV / cm for 20 min, for a total of 10 BV of samples. Then, 24 g of the pretreated D314 was packed into a column (1.6 cm × 30 cm) and loaded at a flow rate of 5 BV / h to treat the samples. The eluent was collected, and the physicochemical properties, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and earth element) were calculated. The results are shown in Tables 2-5.

[0046] The activation method for D314 is as follows: First, soak in anhydrous ethanol for 20 minutes, wash with ultrapure water, then soak in 5 wt% sodium hydroxide solution and 5 wt% hydrochloric acid solution alternately 4 times, 20 minutes each time. The last soaking is in sodium hydroxide solution. Wash with ultrapure water until neutral, and filter for later use.

[0047] Example 2

[0048] Typical samples of fermented baijiu were treated with an electromagnetic field of 50 Hz and 5 kV / cm for 20 min, for a total of 10 BV of samples. Then, 24 g of the pretreated D730 was packed into a column (1.6 cm × 30 cm) and loaded at a flow rate of 5 BV / h. All samples were treated, and the eluent was collected. Physicochemical indicators, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and terbinafine) were calculated. The results are shown in Table 2-5.

[0049] The activation method for D730 is as follows: First, soak it in anhydrous ethanol for 20 minutes, wash it with ultrapure water, and then soak it alternately with 5wt% sodium hydroxide solution and 5wt% hydrochloric acid solution 4 times, each time for 20 minutes. The last soaking is done with sodium hydroxide solution. Wash it with ultrapure water until neutral, and then filter it for later use.

[0050] Example 3

[0051] Typical samples of fermented baijiu were treated with an electromagnetic field of 50 Hz and 5 kV / cm for 20 min, for a total of 10 BV of samples. Then, 24 g of the pretreated DM130 was packed into a column (1.6 cm × 30 cm) and loaded at a flow rate of 5 BV / h. All samples were treated, and the eluent was collected. Physicochemical indicators, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and earth element) were calculated. The results are shown in Table 2-5.

[0052] The activation method for DM130 is as follows: soak in anhydrous ethanol overnight, discard the soaking solution, wash with anhydrous ethanol, and then repeatedly wash with ultrapure water until odorless, and filter for later use.

[0053] Example 4

[0054] Typical samples of fermented baijiu were treated with an electromagnetic field of 50 Hz and 5 kV / cm for 40 min, for a total of 10 BV of samples. Then, 24 g of the pretreated D314 was packed into a column (1.6 cm × 30 cm) and loaded at a flow rate of 5 BV / h. All samples were treated, and the eluent was collected. Physicochemical indicators, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and terbinafine) were calculated. The results are shown in Table 2-5.

[0055] The activation method for D314 is as follows: First, soak in anhydrous ethanol for 20 minutes, wash with ultrapure water, then soak in 5 wt% sodium hydroxide solution and 5 wt% hydrochloric acid solution alternately 4 times, 20 minutes each time. The last soaking is in sodium hydroxide solution. Wash with ultrapure water until neutral, and filter for later use.

[0056] Example 5

[0057] Typical samples of fermented baijiu were treated with an electromagnetic field of 50 Hz and 5 kV / cm for 40 min, for a total of 10 BV of samples. Then, 24 g of the pretreated D730 column (1.6 cm × 30 cm) was packed and loaded at a flow rate of 5 BV / h. All samples were treated, and the eluent was collected. Physicochemical indicators, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and earth element) were calculated. The results are shown in Tables 2-5.

[0058] The activation method for D730 is as follows: First, soak it in anhydrous ethanol for 20 minutes, wash it with ultrapure water, and then soak it alternately with 5wt% sodium hydroxide solution and 5wt% hydrochloric acid solution 4 times, each time for 20 minutes. The last soaking is done with sodium hydroxide solution. Wash it with ultrapure water until neutral, and then filter it for later use.

[0059] Example 6

[0060] Typical samples of fermented baijiu were treated with an electromagnetic field of 50 Hz and 5 kV / cm for 40 min, for a total of 10 BV of samples. Then, 24 g of the pretreated DM130 was packed into a column (1.6 cm × 30 cm) and loaded at a flow rate of 5 BV / h. All samples were treated, and the eluent was collected. Physicochemical indicators, sensory evaluation, retention rates of important flavor compounds (OAV>1), and retention rates of six key fermented baijiu compounds (2-nonanol, trans-2-nonenal, n-decanol, trans-trans-2,4-nonadienal, nonanal, and earth element) were calculated. The results are shown in Table 2-5.

[0061] The activation method for DM130 is as follows: soak in anhydrous ethanol overnight, discard the soaking solution, wash with anhydrous ethanol, and then repeatedly wash with ultrapure water until odorless, and filter for later use.

[0062] Table 2

[0063]

[0064] Table 3

[0065]

[0066]

[0067] Note: Positive numbers indicate an enhanced aroma compared to the original wine, negative numbers indicate a diminished aroma compared to the original wine, and 0 indicates no change.

[0068] Table 4

[0069]

[0070] Table 5

[0071]

[0072]

[0073] Table 2 shows that the shorter the magnetic field treatment time, the less loss of total acids and total esters, with D314 resin showing the least loss of total acids and total esters among the resins. Table 3 shows that the combination of electromagnetic field and macroporous resin adsorption technology in the examples can effectively control the musty odor and irritation, and the control effect on the musty odor is significantly better than that of the individual technologies in Comparative Examples 1 and 2. Among them, the combination of electromagnetic field treatment with D314 resin after 20 minutes effectively controls the musty odor while having less impact on other aroma properties compared to Examples 2, 3, 4, 5, and 6. Table 4 shows that the retention rate of important esters, alcohols, and aldehydes after electromagnetic field treatment with D314 resin after 20 minutes is higher than that in Examples 2, 3, 4, 5, and 6. Table 5 shows that the removal effect of electromagnetic field treatment with D314 resin after 20 minutes on the six key musty odor substances is better than that in Examples 2, 3, 4, 5, and 6.

[0074] The embodiments provided above are not intended to limit the scope of the invention, nor are the described steps intended to limit the order of execution. Any obvious modifications made to the invention by those skilled in the art based on existing common knowledge also fall within the scope of protection defined by the claims.

Claims

1. A method for controlling the lees flavor in baijiu (Chinese liquor), characterized in that, The method includes the following steps: The liquor to be treated is first subjected to electromagnetic field treatment, and then subjected to dynamic adsorption treatment with activated macroporous resin to obtain liquor with removed lees flavor. The conditions for electromagnetic field treatment are: frequency 10-100 Hz, electric field strength 5-10 kV / cm, and treatment time 20-40 min. The macroporous resin is one or more of D314 and DM130.

2. The method according to claim 1, characterized in that, The activation method of DM130 macroporous adsorption resin is as follows: soak in anhydrous ethanol overnight, discard the soaking solution, wash with anhydrous ethanol, and then wash repeatedly with ultrapure water until odorless, and filter out for use.

3. The method according to claim 1, characterized in that, The activation method for D314 anion exchange resin is as follows: after soaking the macroporous resin in anhydrous ethanol, it is then soaked alternately in alkali and acid.

4. The method according to claim 1, characterized in that, During the dynamic adsorption process, activated macroporous resin is packed into an atmospheric pressure chromatography column with a column diameter ratio of 15-25.

5. The method according to claim 4, characterized in that, During the dynamic adsorption process, the activated macroporous resin accounts for 70-90% of the column volume.

6. The method according to claim 4, characterized in that, During dynamic adsorption, the sample loading amount is 6-10 BV.

7. The method according to claim 4, characterized in that, During dynamic adsorption, the sample loading flow rate is 3-7 BV / h.

8. The application of the method according to any one of claims 1-7 in the liquor processing process.

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