阅读说明：本技术 一种表征再造烟叶浆料新鲜度的方法 (Method for representing freshness of reconstituted tobacco pulp ) 是由 李华雨 李晓瑜 薛建中 王茹楠 许红涛 刘宁 王毅博 祖萌萌 于 2021-07-09 设计创作，主要内容包括：本发明涉及一种表征再造烟叶浆料新鲜度的方法,通过再造烟叶浆料新鲜度的特征成分确定；通过表征再造烟叶浆料新鲜度的特征成分量的变化与感官的关系；进行再造烟叶浆料中NO-(3)～(-)测定的方法实现对再造烟叶浆料新鲜度的快速检测。本技术方案可根据再造烟叶浆料中NO-(3)～(-)离子含量的变化率来判断上网浆料是否新鲜,是否可以生产使用。该法简单、快速,解决了再造烟叶生产对上网浆料质量评价的不确定性和滞后性问题,保证了再造烟叶产品质量的安全,减少了生产线的污染,提高了生产效能。(The invention relates to a method for representing the freshness of reconstituted tobacco pulp, which is determined by the characteristic components of the freshness of the reconstituted tobacco pulp; the method comprises the steps of (1) representing the relationship between the change of characteristic component quantity of the freshness of reconstituted tobacco pulp and senses; NO in reconstituted tobacco pulp 3 ‑ The determination method realizes the rapid detection of the freshness of the reconstituted tobacco pulp. The present technologyThe scheme can be based on NO in the reconstituted tobacco pulp 3 ‑ And judging whether the upper-mesh slurry is fresh or not according to the change rate of the ion content and whether the upper-mesh slurry can be produced and used or not. The method is simple and rapid, solves the problems of uncertainty and hysteresis of reconstituted tobacco production on the quality evaluation of the pulp on the net, ensures the safety of reconstituted tobacco product quality, reduces the pollution of a production line, and improves the production efficiency.)

1. A method for representing the freshness of reconstituted tobacco pulp is characterized by comprising the following steps:

s1, determining characteristic components of freshness of reconstituted tobacco pulp

Measuring the content change states of isovaleric acid and nitrate ions in reconstituted tobacco pulp which is oscillated and placed in a sealed state within a first set time by utilizing a solid-phase extraction ion chromatography;

summarizing the change percentage of the isovaleric acid and nitrate radical ions in different reconstituted tobacco pulp along with the oscillation time relative to the fresh pulp;

performing correlation analysis on the content changes of isovaleric acid and nitrate radical, and determining that the change trend of the content of nitrate radical ions in the slurry is extremely obviously correlated;

s2, determining the variation of the characteristic components when the reconstituted tobacco pulp is not fresh

Different reconstituted tobacco pulp is oscillated and placed in a closed state for a second set time to prepare pulp base pieces according to a papermaking method, and the prepared pulp base pieces are evaluated for smoking according to a sensory evaluation method;

the sensory evaluation result is consistent with the change percentage result of the nitrate ions in the slurry relative to the fresh slurry along with the oscillation time, and the nitrate ions in the slurry are determined to be selected as characteristic ions for representing the freshness of the slurry for monitoring;

s3, adding NO in the pulp in the production process of reconstituted tobacco₃ ^-Monitoring of content changes

Monitoring slurry NO in reconstituted tobacco production process by adopting liquid chromatography or rapid method₃ ^-The amount of the compound is changed.

2. The method of characterizing reconstituted tobacco slurry freshness according to claim 1, wherein the first set time and the second set time are both 12 hours.

3. The method for characterizing the freshness of reconstituted tobacco pulp according to claim 1, wherein the sensory evaluation result is that the pulp base shows a significant decrease in sensory quality with the increase of the oscillation time of the pulp.

4. The method for characterizing the freshness of reconstituted tobacco pulp according to claim 3, wherein the obvious decrease in sensory quality is represented by a trend of gradually increasing oral cavity stimulation, oral cavity residue and nasal cavity stimulation, gradually decreasing aroma amount, and gradually decreasing aroma richness and fine and smooth roundness.

5. The method of claim 1, wherein the freshness of the reconstituted tobacco pulp needs to be further confirmed when the content of nitrate ions in the reconstituted tobacco material is reduced by about 50% compared to the fresh pulp.

6. The method for characterizing the freshness of reconstituted tobacco pulp according to claim 1, wherein the liquid chromatography comprises the steps of:

1) filtering the reconstituted tobacco slurry by using 400-mesh and 600-mesh filter cloth, and removing larger fibers and part of fine fibers in the slurry;

2) centrifuging the filtered filtrate for 10min at 12000r/min for 50-100mL to remove macromolecular substances in the filtrate;

3) taking 25mL of centrifuged supernatant, adding 2.0g of activated carbon with the particle size of 50-100 mu m, fully shaking, standing for 10min, performing suction filtration by using quantitative filter paper, and filtering the suction filtration liquid by using a 0.45 mu m water system needle filter for analysis; or 5mL of the centrifuged supernatant is taken to pass through an activated carbon type solid-phase extraction column, and the effluent is taken to be analyzed by a 0.45-micron water system needle type filter;

4) determination of NO in reconstituted tobacco pulp by liquid chromatography₃ ^-The content of ions.

7. The method of characterizing reconstituted tobacco pulp freshness according to claim 1, wherein the rapid method comprises the steps of:

11) filtering the reconstituted tobacco slurry by using 400-mesh and 600-mesh filter cloth, and removing larger fibers and part of fine fibers in the slurry;

21) centrifuging the filtered filtrate for 10min at 12000r/min in 50-100mL, and removing macromolecular substances in the filtrate;

31) taking 25mL of centrifuged supernatant, adding 2.0g of activated carbon with the particle size of 50-100 mu m, fully shaking, standing for 10min, performing suction filtration by using quantitative filter paper, and filtering the suction filtration liquid by using a 0.45 mu m water system needle filter for analysis; or 5mL of the centrifuged supernatant is taken to pass through an activated carbon type solid-phase extraction column, and the effluent is taken to be analyzed by a 0.45-micron water system needle type filter;

4) kit for rapidly determining NO in sample by using nitrate determination by cadmium reduction method or nitrate determination by chromium acid change method₃ ^-And (4) content.

Technical Field

The invention belongs to the technical field of reconstituted tobacco processing detection, and particularly relates to a method for representing freshness of reconstituted tobacco pulp.

Background

The production of the paper-making reconstituted tobacco uses the pulping and papermaking technology in the paper-making industry as reference, wherein the pulping process is a process of separating fibers from fibers in tobacco stems or tobacco powder by a pulping machine under the action of mechanical force, and a large amount of components such as protein, polysaccharide, inorganic salt and the like can be separated in the pulping process. In the slurry operation process, the temperature is generally maintained at about 50 ℃, organic substances such as inorganic salt, polysaccharide and the like in the system provide a relatively suitable growth environment for the growth of microorganisms, and the slurry is acidified and deteriorated when the slurry stays for a relatively long time, so that the sensory quality of a product is influenced, a production line is polluted, and the production efficiency is influenced.

In the production process of the paper-making reconstituted tobacco, the problem of microbial pollution in a system cannot be solved by adding a sterilization preservative, microorganisms, an enzyme preparation, a flocculating agent and the like in the paper-making industry, but the breeding of microorganisms is prevented by adopting methods of increasing the running temperature of slurry, reducing the recycling of white water and the like. Evaluation of the freshness of the slurry is typically based on production run experience and final product sensory quality assessment with uncertainty and hysteresis in the control of the slurry quality.

Disclosure of Invention

The invention aims to provide a method for representing the freshness of reconstituted tobacco pulp, which is used for solving the problems of uncertainty and hysteresis in the control of the pulp quality.

In order to realize the purpose, the invention is realized by the following technical scheme:

a method for representing the freshness of reconstituted tobacco pulp comprises the following steps:

s1, determining characteristic components of freshness of reconstituted tobacco pulp

Measuring the content change states of isovaleric acid and nitrate ions in reconstituted tobacco pulp which is oscillated and placed in a sealed state within a first set time by utilizing a solid-phase extraction ion chromatography;

summarizing the percentage change of isovaleric acid and nitrate radical ions in different slurries with the oscillation time relative to the fresh slurries;

performing correlation analysis on the content changes of isovaleric acid and nitrate radical, and determining that the change trend of the content of nitrate radical ions in the slurry is extremely obviously correlated;

s2, determining the variation of the characteristic components when the reconstituted tobacco pulp is not fresh

Different reconstituted tobacco pulp is oscillated and placed in a closed state for a second set time to prepare pulp base pieces according to a papermaking method, and the prepared pulp base pieces are evaluated for smoking according to a sensory evaluation method;

the sensory evaluation result is consistent with the change percentage result of the nitrate ions in the slurry relative to the fresh slurry along with the oscillation time, and the nitrate ions in the slurry are determined to be selected as characteristic ions for representing the freshness of the slurry for monitoring;

s3, adding NO in the pulp in the production process of reconstituted tobacco₃ ^-Monitoring of content changes

Monitoring slurry NO in reconstituted tobacco production process by adopting liquid chromatography or rapid method₃ ^-The amount of the compound is changed.

Further, the first set time and the second set time are both 12 hours.

Further, the sensory evaluation results show that the base of the slurry tablet shows a significant decrease in sensory quality with the increase in the slurry oscillation time.

Furthermore, the obvious decline of the sensory quality is represented by the trends of gradually increasing oral cavity stimulation, oral cavity residue and nasal cavity stimulation, gradually reducing aroma amount, and gradually reducing aroma richness and fine and smooth smoothness.

Further, when the content of nitrate ions in the reconstituted tobacco pulp is reduced by about 50% compared with that of fresh pulp, the pulp is not fresh any more.

Further, the liquid chromatography comprises the following steps:

1) filtering the reconstituted tobacco slurry by using 400-mesh and 600-mesh filter cloth, and removing larger fibers and part of fine fibers in the slurry;

2) centrifuging the filtered filtrate for 10min at 12000r/min for 50-100mL to remove macromolecular substances in the filtrate;

3) taking 25mL of centrifuged supernatant, adding 2.0g of activated carbon with the particle size of 50-100 mu m, fully shaking, standing for 10min, performing suction filtration by using quantitative filter paper, and filtering the suction filtration liquid by using a 0.45 mu m water system needle filter for analysis; or 5mL of the centrifuged supernatant is taken to pass through an activated carbon type solid-phase extraction column, and the effluent is taken to be analyzed by a 0.45-micron water system needle type filter;

4) determination of NO in reconstituted tobacco pulp by liquid chromatography₃ ^-The content of ions.

Further, the rapid method comprises the following steps:

11) filtering the reconstituted tobacco slurry by using 400-mesh and 600-mesh filter cloth, and removing larger fibers and part of fine fibers in the slurry;

21) centrifuging the filtered filtrate for 10min at 12000r/min in 50-100mL, and removing macromolecular substances in the filtrate;

31) taking 25mL of centrifuged supernatant, adding 2.0g of activated carbon with the particle size of 50-100 mu m, fully shaking, standing for 10min, performing suction filtration by using quantitative filter paper, and filtering the suction filtration liquid by using a 0.45 mu m water system needle filter for analysis; or 5mL of the centrifuged supernatant is taken to pass through an activated carbon type solid-phase extraction column, and the effluent is taken to be analyzed by a 0.45-micron water system needle type filter;

4) rapid determination sample of kit for determining nitrate by cadmium reduction method or determining nitrate by chromium acid change methodNO in product₃ ^-And (4) content.

The invention has the beneficial effects that:

the technical scheme can be based on NO in the reconstituted tobacco pulp₃ ^-And judging whether the upper-mesh slurry is fresh or not according to the change rate of the ion content and whether the upper-mesh slurry can be produced and used or not. The method is simple and rapid, solves the problems of uncertainty and hysteresis of reconstituted tobacco production on the quality evaluation of the pulp on the net, ensures the safety of reconstituted tobacco product quality, reduces the pollution of a production line, and improves the production efficiency.

Drawings

FIGS. 1 and 2 show the aroma style characteristics of the base sheet after the reconstituted tobacco pulp is manufactured and molded by paper making with different oscillation times.

Detailed Description

The technical solutions of the present invention are described in detail below by examples, and the following examples are only exemplary and can be used only for explaining and explaining the technical solutions of the present invention, but not construed as limiting the technical solutions of the present invention.

According to the technical scheme, firstly, the characteristic component of the freshness of the reconstituted tobacco pulp is determined, then the relation between the change of the characteristic component representing the freshness of the reconstituted tobacco pulp and the sense organ is utilized, and finally NO in the reconstituted tobacco pulp is carried out₃ ^-The determination method realizes the rapid detection of the freshness of the reconstituted tobacco pulp.

The application provides a method for representing freshness of reconstituted tobacco pulp, which comprises the following steps:

determining characteristic components for representing freshness of reconstituted tobacco pulp

The content of isovaleric acid and nitrate ion in reconstituted tobacco slurry with different time periods and different product specifications is measured by online solid phase extraction ion chromatography in a closed state in a vibration and placement mode within 12 hours, the specific data are shown in table 1, and it can be known that the content of nitrate ion in the slurry of products A-1 and A-2 has no obvious change within 3 hours of vibration, is sharply reduced within 4 hours to 5 hours of vibration, and then has no obvious change. The content of nitrate ions in the B-1 and B-2 product slurry does not change obviously within 4 hours of oscillation, the content of the nitrate ions is reduced quickly within 5 to 8 hours of oscillation, and the content is low and does not change obviously after 9 hours of oscillation. The content of isovaleric acid in the slurry is sharply reduced after gradually increasing along with the extension of the oscillation time, and has no obvious change trend after 9 hours, and reaches the maximum value when oscillating for 3 hours or 4 hours. The content of isovaleric acid in different slurries changes greatly in a fast interval along with the decrease of the oscillation time.

TABLE 1 content of Isovaleric acid and nitrate ion in different reconstituted tobacco slurries

The percent change in isovaleric acid and nitrate ion with shaking time versus their fresh slurries for different product specifications is summarized in table 2 (fresh slurries are run slurries freshly prepared in the plant). It is found that the nitrate ion content in the A-1 and A-2 slurries decreased by about 80% to 98% when the slurries were subjected to closed shaking for 5 hours, and the nitrate ion content in the B-1 and B-2 slurries decreased by about 50% when the slurries were subjected to closed shaking for 6 hours. The content of the isovaleric acid in the B-1 and B-2 slurry begins to be reduced by about 12-16% when the slurry is subjected to closed oscillation for 5 hours, the content of the isovaleric acid in the A-1 slurry begins to be reduced by about 7% when the slurry is subjected to oscillation for 6 hours, and the content of the isovaleric acid in the A-2 slurry begins to be reduced by about 17% when the slurry is subjected to oscillation for 9 hours.

The correlation analysis is carried out on the content changes of isovaleric acid and nitrate radical, and the change trend of the content of the nitrate radical ions in the workshop A-1 slurry is very obviously related to the change trend of the content of the nitrate radical ions in the workshop A-2 slurry, the workshop B-1 slurry and the workshop B-2 slurry respectively (p is less than 0.01). The change trend of the content of the isovaleric acid in the workshop A-1 slurry is obviously related to the change trend of the content of the isovaleric acid in the workshop A-2 slurry (p is less than 0.05), and the correlation between the change trend of the content of the isovaleric acid in the workshop A-2 slurry and the change trend of the workshop B-2 slurry is not obvious.

Table 2 percentage change of iso-valeric acid and nitrate ions in different slurries with respect to their fresh slurries (%)

Nitrate ions in the slurry were therefore selected for monitoring as the characteristic ion for slurry freshness indication.

Secondly, determining the variation of the characteristic components when the reconstituted tobacco pulp is not fresh

Oscillating and placing reconstituted tobacco pulp with different product specifications for 12h in a closed state, taking pulp in different periods of time to prepare pulp base sheets according to a papermaking method, and performing smoking evaluation on the prepared pulp base sheets according to a sensory evaluation method, wherein the results are shown in fig. 1 and fig. 2. The result shows that along with the extension of the oscillation time of the sizing agent, the sizing agent base shows the trends that the stimulation of the oral cavity, the residue of the oral cavity and the stimulation of the nasal cavity are gradually increased, the fragrance quantity is gradually reduced, and the richness and the fineness and the smoothness of the fragrance are gradually reduced. After the A-2 slurry is oscillated for 5 hours, the oral cavity stimulation, the oral cavity residue and the nasal cavity stimulation of the film base are in a non-changing state. After the A-2 slurry is oscillated for 7 hours, the smoke concentration of the substrate is slightly increased, and the protein and the starch are probably decomposed by microorganisms. After the B-2 slurry is oscillated for 6 hours, the aroma richness and the fine and smooth roundness of the substrate are not obviously changed, and the smoke concentration of the substrate is not obviously changed within 9 hours of the slurry oscillation.

The above analysis shows that the sensory quality of the A-2 and B-2 sizing agents is obviously reduced after the oscillation is carried out for 5 hours and 6 hours respectively, and the sensory quality is mainly shown in the aspects of reduced aroma, increased miscellaneous gas, increased irritation, poorer oral cavity comfort and the like. And judging the pulp to be unqualified according to the production experience.

The sensory evaluation results of the A-2 and B-2 slurry base are consistent with the change rule of nitrate ions in the slurry along with the oscillation time. The sensory evaluation results of the pulp base are consistent with the results of the percentage change of the nitrate ions in the pulp relative to the fresh pulp along with the oscillation time, so that the nitrate ions in the pulp are selected as characteristic ions for representing the freshness of the pulp to be monitored, and when the content of the nitrate ions in the reconstituted tobacco pulp is reduced by about 50 percent compared with the content of the nitrate ions in the fresh pulp, the pulp cannot be used. The quality of the reconstituted tobacco pulp on the net can be monitored, and the stability of the reconstituted tobacco product quality can be ensured.

Third, NO in pulp in the production process of reconstituted tobacco₃ ^-Monitoring of content changes

1. Liquid chromatography for monitoring slurry NO in reconstituted tobacco production process₃ ^-The content change comprises the following steps:

1) the reconstituted tobacco slurry is filtered by 400-mesh 600-mesh filter cloth, and larger fibers and part of fine fibers in the slurry are removed.

2) And (3) centrifuging the filtered filtrate for 10min at 12000r/min in 50-100mL of the filtrate, and removing macromolecular substances such as protein, pectin and the like in the filtrate.

3) Taking 25mL of centrifuged supernatant, adding 2.0g of activated carbon (activated carbon particles are 50-100 mu m), fully shaking, standing for 10min, performing suction filtration by using quantitative filter paper, and filtering the suction filtration liquid by using a 0.45 mu m water system needle filter for analysis; alternatively, 5mL of the centrifuged supernatant was passed through an activated carbon-type solid phase extraction column (SPE), and the effluent was analyzed on a 0.45 μm aqueous needle filter (250 mg/3mL or 300mg/6mL of SPE column is acceptable). The purpose is to remove organic interfering substances such as pigments.

4) Determination of NO in reconstituted tobacco pulp by liquid chromatography₃ ^-The content of ions;

chromatographic conditions are as follows: a chromatographic column: 250mm × 4.6mm (5 μm); 0.03mol/L KH₂PO⁴-H₃PO⁴Buffer mobile phase, pH 3.6; flow rate: 0.6 mL/min; detection wavelength: 217 nm; column temperature: 40 ℃; sample introduction amount: 5 μ L.

Drawing a standard working curve: respectively preparing standard working solution containing 2.5, 4, 5, 10 and 20mg/L of nitrate and nitrite, and measuring by high performance liquid chromatography. And drawing a standard working curve by taking the peak height as an ordinate and the contents of nitrate and nitrite in the sample as an abscissa.

And (3) sample determination: the samples were tested according to the instrumental test conditions and quantified by retention time and external standard.

The results show that: when the content of nitrate ions in the reconstituted tobacco pulp is reduced by about 50 percent compared with that of fresh pulp, the reconstituted tobacco pulp needs to be used with caution, and the pulp may be stale or deteriorated.

2. Rapid method for monitoring slurry NO in reconstituted tobacco production process₃ ^-The content of the compound is changed by the following stepsThe method comprises the following steps:

1) the reconstituted tobacco slurry is filtered by 400-mesh 600-mesh filter cloth, and larger fibers and part of fine fibers in the slurry are removed.

2) And (3) centrifuging the filtered filtrate for 10min at 12000r/min in 50-100mL of the filtrate, and removing macromolecular substances such as protein, pectin and the like in the filtrate.

3) Taking 25mL of centrifuged supernatant, adding 2.0g of activated carbon (activated carbon particles are 50-100 mu m), fully shaking, standing for 10min, performing suction filtration by using quantitative filter paper, and filtering the suction filtration liquid by using a 0.45 mu m water system needle filter for analysis; alternatively, 5mL of the centrifuged supernatant was passed through an activated carbon-type solid phase extraction column (SPE), and the effluent was analyzed on a 0.45 μm aqueous needle filter (250 mg/3mL or 300mg/6mL of SPE column is acceptable). The purpose is to remove organic interfering substances such as pigments.

4) And (3) sample determination: kit for rapidly determining NO in sample by using nitrate determination by cadmium reduction method or nitrate determination by chromium acid change method₃ ^-And (4) content.

The results show that: when the content of nitrate ions in the reconstituted tobacco pulp is reduced by about 50 percent compared with that of fresh pulp, the reconstituted tobacco pulp needs to be used with caution, and the pulp may be stale or deteriorated.

Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.