2023 Vol. 38, No. 3
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2023, 38(3)
:1-10.
doi: 10.12187/2023.03.001
Abstract:
In this study, five anthocyanin pigments were extracted from Xinjiang characteristic plants, and the physicochemical properties, antioxidant activities and degradation kinetics of these pigment extracts were explored. The results showed that there were significant differences in color responses of different pigment extracts (P<0.05). The black wolfberry pigments (BWP), medicine mulberry pigments (MMP), rose flower pigments (RFP), grape peel pigments (GPP), and perilla leaf pigments (PLP) mainly contained 5 compounds, 4 compounds, 7 compounds, 7 compounds, and 3 compounds, respectively. The compounds with the highest content in five pigment extracts were malvidin 3-O-glucoside (23.18 μg/g DW), cyanidin-3-galactoside (300.87 μg/g DW), delphinidin-3-O-glucoside (144.34 μg/g DW), delphinidin-3-O-glucoside (116.45 μg/g DW), and cyanidin (144.10 μg/g DW), respectively. Furthermore, GPP showed the highest heat resistance with a degradation temperature of 165.71 ℃. The thermal degradation of different pigment extracts conformed to the first-order reaction kinetics. Meanwhile, PLP showed the highest stability at pH 3.0, with a corresponding energy of activation (Ea) was 22.539 kJ/mol. RFP was the most stable at pH 7.0 (Ea=13.851 kJ/mol). Correlation analysis showed that there was a significant correlation between the content of anthocyanins in pigment extracts and their antioxidant activity (P<0.05). In addition, RFP exhibited the strongest antioxidant activities in vitro, and its 50% inhibiting concentration (IC50) on DPPH and ABTS radicals were 7.32 μg/mL and 71.50 μg/mL, respectively, the total antioxidant activity (T-AOC) was 4 073.00 U/g DW.
In this study, five anthocyanin pigments were extracted from Xinjiang characteristic plants, and the physicochemical properties, antioxidant activities and degradation kinetics of these pigment extracts were explored. The results showed that there were significant differences in color responses of different pigment extracts (P<0.05). The black wolfberry pigments (BWP), medicine mulberry pigments (MMP), rose flower pigments (RFP), grape peel pigments (GPP), and perilla leaf pigments (PLP) mainly contained 5 compounds, 4 compounds, 7 compounds, 7 compounds, and 3 compounds, respectively. The compounds with the highest content in five pigment extracts were malvidin 3-O-glucoside (23.18 μg/g DW), cyanidin-3-galactoside (300.87 μg/g DW), delphinidin-3-O-glucoside (144.34 μg/g DW), delphinidin-3-O-glucoside (116.45 μg/g DW), and cyanidin (144.10 μg/g DW), respectively. Furthermore, GPP showed the highest heat resistance with a degradation temperature of 165.71 ℃. The thermal degradation of different pigment extracts conformed to the first-order reaction kinetics. Meanwhile, PLP showed the highest stability at pH 3.0, with a corresponding energy of activation (Ea) was 22.539 kJ/mol. RFP was the most stable at pH 7.0 (Ea=13.851 kJ/mol). Correlation analysis showed that there was a significant correlation between the content of anthocyanins in pigment extracts and their antioxidant activity (P<0.05). In addition, RFP exhibited the strongest antioxidant activities in vitro, and its 50% inhibiting concentration (IC50) on DPPH and ABTS radicals were 7.32 μg/mL and 71.50 μg/mL, respectively, the total antioxidant activity (T-AOC) was 4 073.00 U/g DW.
2023, 38(3)
:11-16.
doi: 10.12187/2023.03.002
Abstract:
Given that wet experimental methods were no longer adequate for the rapid identification of bitter peptides, this paper presented Bitter-Fus, a novel predictive deep learning method incorporating traditional manual features and pre-trained deep features. Firstly, the method automatically extracted deep learning features from peptide sequences using a pre-trained protein sequence language model, then fed the deep learning features into a long short-term memory (LSTM) network for dimensionality reduction to retain the most relevant features. Finally, the reduced-dimensional deep features were fused with the manual features composed of traditional amino acids composition (AAC) method and passed into the feedforward neural network to construct a prediction model. The validation experimental results showed that the prediction method Bitter-Fus obtained an accuracy precision value of 0.902 and a Mathews correlation coefficient value of 0.805 in a 10-fold cross-validation, and an accuracy precision value of 0.930 and a Mathews correlation coefficient value of 0.862 in the independent dataset test, which significantly outperformed the current state-of-the-art bitter peptide prediction methods BERT4Bitter and iBitter-SCM.
Given that wet experimental methods were no longer adequate for the rapid identification of bitter peptides, this paper presented Bitter-Fus, a novel predictive deep learning method incorporating traditional manual features and pre-trained deep features. Firstly, the method automatically extracted deep learning features from peptide sequences using a pre-trained protein sequence language model, then fed the deep learning features into a long short-term memory (LSTM) network for dimensionality reduction to retain the most relevant features. Finally, the reduced-dimensional deep features were fused with the manual features composed of traditional amino acids composition (AAC) method and passed into the feedforward neural network to construct a prediction model. The validation experimental results showed that the prediction method Bitter-Fus obtained an accuracy precision value of 0.902 and a Mathews correlation coefficient value of 0.805 in a 10-fold cross-validation, and an accuracy precision value of 0.930 and a Mathews correlation coefficient value of 0.862 in the independent dataset test, which significantly outperformed the current state-of-the-art bitter peptide prediction methods BERT4Bitter and iBitter-SCM.
2023, 38(3)
:17-24,54.
doi: 10.12187/2023.03.003
Abstract:
The effects of dielectric barrier discharge (DBD) plasma on the inactivation effect, the cell morphology, membrane changes and intracellular reactive oxygen species (ROS) levels of Listeria monocytogenes were investigated by scanning electron microscopy (SEM), flow cytometry, fluorescence staining and so on. The results showed that the population of L.monocytogenes was reduced from an initial level of 8.26 lg CFU/mL to 1.30 lg CFU/mL after DBD plasma treatment at 20.8 W for 80 s, and the intracellular ROS level increased by 9.5-folds (P<0.05). DBD plasma treatment caused damage in the morphology and cell membrane of L.monocytogenes in a treatment time-dependent manner. Moreover, DBD plasma caused the depolarization of the cell membrane of L.monocytogenes. In addition, after DBD plasma treatment, the pH value of normal saline decreased significantly, the oxidation-reduction potential and concentration of NO3-, NO-2 and H2O2 increased significantly. In summary, DBD plasma could inactivate L.monocytogenes by disrupting cell membranes and inducing oxidative stress damage.
The effects of dielectric barrier discharge (DBD) plasma on the inactivation effect, the cell morphology, membrane changes and intracellular reactive oxygen species (ROS) levels of Listeria monocytogenes were investigated by scanning electron microscopy (SEM), flow cytometry, fluorescence staining and so on. The results showed that the population of L.monocytogenes was reduced from an initial level of 8.26 lg CFU/mL to 1.30 lg CFU/mL after DBD plasma treatment at 20.8 W for 80 s, and the intracellular ROS level increased by 9.5-folds (P<0.05). DBD plasma treatment caused damage in the morphology and cell membrane of L.monocytogenes in a treatment time-dependent manner. Moreover, DBD plasma caused the depolarization of the cell membrane of L.monocytogenes. In addition, after DBD plasma treatment, the pH value of normal saline decreased significantly, the oxidation-reduction potential and concentration of NO3-, NO-2 and H2O2 increased significantly. In summary, DBD plasma could inactivate L.monocytogenes by disrupting cell membranes and inducing oxidative stress damage.
2023, 38(3)
:25-34.
doi: 10.12187/2023.03.004
Abstract:
The changes of volatile components of fresh Toona sinensis, different dried (vacuum microwave drying, heat pump drying, vacuum freeze drying) T.sinensis samples and their rehydrated samples were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS) coupled with principal component analysis(PCA) to investigate the effects of different drying methods on the appearance, types and contents of volatile components of T.sinensis. The results showed that the T.sinensis samples by vacuum freeze-drying had attractive color, lower shrinkage and lowest rehydration. A total of 40 volatile components were identified in different dried T.sinensis samples, and 44 volatile components were identified in different dried T.sinensis rehydration samples. Fresh T.sinensis as a control, the rehydrated vacuum freeze-dried T.sinensis samples retained more components and the most newly produced compounds, while the rehydrated vacuum microwave-dried T.sinensis samples retained the least components. The principal component analysis distinguished well between different dried T.sinensis and different rehydrated samples, where the flavor of the vacuum microwave dried samples was similar to that of the heat pump dried samples. In a comprehensive comparison, vacuum freeze drying was more suitable for the preservation and recovery of T.sinensis flavor, and was a suitable drying method for T.sinensis processed products.
The changes of volatile components of fresh Toona sinensis, different dried (vacuum microwave drying, heat pump drying, vacuum freeze drying) T.sinensis samples and their rehydrated samples were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS) coupled with principal component analysis(PCA) to investigate the effects of different drying methods on the appearance, types and contents of volatile components of T.sinensis. The results showed that the T.sinensis samples by vacuum freeze-drying had attractive color, lower shrinkage and lowest rehydration. A total of 40 volatile components were identified in different dried T.sinensis samples, and 44 volatile components were identified in different dried T.sinensis rehydration samples. Fresh T.sinensis as a control, the rehydrated vacuum freeze-dried T.sinensis samples retained more components and the most newly produced compounds, while the rehydrated vacuum microwave-dried T.sinensis samples retained the least components. The principal component analysis distinguished well between different dried T.sinensis and different rehydrated samples, where the flavor of the vacuum microwave dried samples was similar to that of the heat pump dried samples. In a comprehensive comparison, vacuum freeze drying was more suitable for the preservation and recovery of T.sinensis flavor, and was a suitable drying method for T.sinensis processed products.
2023, 38(3)
:35-45.
doi: 10.12187/2023.03.005
Abstract:
Taking two commercial Toona sinensis tea (Sanyi T.sinensis tea and Anhui T.sinensis tea) as the research object, the differences in their main active components, antioxidant activity and volatile components were detected and compared by UV spectrophotometry, gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) techniques. The results showed that the contents of caffeine and the ratio of phenol to ammonia of Sanyi T.sinensis tea were significantly higher than those of Anhui T.sinensis tea, while the contents of other active ingredients (such as water extracts, total free amino acid, tea polyphenols, et al.) were the opposite. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging capacity and total reducing capacity of Sanyi T.sinensis tea were slightly lower than those of Anhui T.sinensis tea, but the hydroxyl radical (·OH) scavenging capacity was higher than that of Anhui T.sinensistea. A total of 90 and 75 different volatile components were detected in two commercial T.sinensis tea samples, mainly hydrocarbons, alcohols and aldehydes. The results of GC-MS indicated that geraniol, benzaldehyde and methyl salicylate were higher in Sanyi T.sinensistea, and β-caryophyllene, α-caryophyllene and α-farnesene were higher in Anhui T.sinensis tea. GC-IMS indicated that the main volatile components in Sani T.sinensis tea were aldehydes, alcohols and ketones, and the types and contents of aldehydes in Anhui T.sinensistea were the highesT.The volatile components in the two commercial T.sinensistea could be well distinguished by GC-IMS fingerprint and PCA analysis. Using these two combined techniques for collaborative analysis, the flavor information of T.sinensis tea can be obtained more comprehensively, which provides a reference for improving the flavor of T.sinensis tea.
Taking two commercial Toona sinensis tea (Sanyi T.sinensis tea and Anhui T.sinensis tea) as the research object, the differences in their main active components, antioxidant activity and volatile components were detected and compared by UV spectrophotometry, gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) techniques. The results showed that the contents of caffeine and the ratio of phenol to ammonia of Sanyi T.sinensis tea were significantly higher than those of Anhui T.sinensis tea, while the contents of other active ingredients (such as water extracts, total free amino acid, tea polyphenols, et al.) were the opposite. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging capacity and total reducing capacity of Sanyi T.sinensis tea were slightly lower than those of Anhui T.sinensis tea, but the hydroxyl radical (·OH) scavenging capacity was higher than that of Anhui T.sinensistea. A total of 90 and 75 different volatile components were detected in two commercial T.sinensis tea samples, mainly hydrocarbons, alcohols and aldehydes. The results of GC-MS indicated that geraniol, benzaldehyde and methyl salicylate were higher in Sanyi T.sinensistea, and β-caryophyllene, α-caryophyllene and α-farnesene were higher in Anhui T.sinensis tea. GC-IMS indicated that the main volatile components in Sani T.sinensis tea were aldehydes, alcohols and ketones, and the types and contents of aldehydes in Anhui T.sinensistea were the highesT.The volatile components in the two commercial T.sinensistea could be well distinguished by GC-IMS fingerprint and PCA analysis. Using these two combined techniques for collaborative analysis, the flavor information of T.sinensis tea can be obtained more comprehensively, which provides a reference for improving the flavor of T.sinensis tea.
2023, 38(3)
:46-54.
doi: 10.12187/2023.03.006
Abstract:
Selenium enriched passion fruit seed oil was prepared by supercritical CO2 extraction method with Selenium enriched passion fruit seed as raw material. Based on single factor experiment, RSM-CCD (response surface curve-central composite design) was used to explore the effects of temperature, pressure, static extraction time, dynamic extraction time and CO2 flow rate on the extraction rate of Selenium enriched passion fruit seed oil. And the physical and chemical properties, fatty acid content and antioxidant activity of selenium-rich passionfruit seed oil extracted by supercritical CO2extraction and Soxhlet extraction were investigated. The results showed that optimal process parameters of supercritical CO2 extraction for oil from Selenium enriched passion seed was found to be extraction temperature of 50 ℃,extraction pressure of 34 MPa,static extraction of 109 min,dynamic extraction of 97 min, CO2 flow rate of 1.0 L/min. Under this condition, the actual Selenium enriched passion seed oil was clear light yellow liquid, and the yield was 72.33%. The content of unsaturated fatty acids extracted by supercritical CO2 extraction was 80.11%, which was slightly higher than that extracted by soxhlet extraction (78.71%); Acid value, peroxide value, oxidation resistance and other properties also showed that the quality of oil extracted by supercritical CO2 extraction was better than that extracted by Soxhlet extraction.
Selenium enriched passion fruit seed oil was prepared by supercritical CO2 extraction method with Selenium enriched passion fruit seed as raw material. Based on single factor experiment, RSM-CCD (response surface curve-central composite design) was used to explore the effects of temperature, pressure, static extraction time, dynamic extraction time and CO2 flow rate on the extraction rate of Selenium enriched passion fruit seed oil. And the physical and chemical properties, fatty acid content and antioxidant activity of selenium-rich passionfruit seed oil extracted by supercritical CO2extraction and Soxhlet extraction were investigated. The results showed that optimal process parameters of supercritical CO2 extraction for oil from Selenium enriched passion seed was found to be extraction temperature of 50 ℃,extraction pressure of 34 MPa,static extraction of 109 min,dynamic extraction of 97 min, CO2 flow rate of 1.0 L/min. Under this condition, the actual Selenium enriched passion seed oil was clear light yellow liquid, and the yield was 72.33%. The content of unsaturated fatty acids extracted by supercritical CO2 extraction was 80.11%, which was slightly higher than that extracted by soxhlet extraction (78.71%); Acid value, peroxide value, oxidation resistance and other properties also showed that the quality of oil extracted by supercritical CO2 extraction was better than that extracted by Soxhlet extraction.
2023, 38(3)
:55-62.
doi: 10.12187/2023.03.007
Abstract:
Based on the necessity of plant polysaccharide degradation, the degradation methods of plant polysaccharides and the physicochemical properties and biological activities of the degradation products were reviewed as follows. The chemical degradation method was simple and easy to implement, and had low requirements for degradation equipment, but there were problems such as difficult separation of degradation products and environmental pollution; the biodegradation method had mild reaction conditions, fast degradation rate and uniform products, but there were high degradation costs, strict requirements for conditions; the synergistic use of multiple degradation methods could make up for the shortcomings of a single degradation method and improved the degradation efficiency of plant polysaccharides; degradation could significantly reduce the molecular weight and intrinsic viscosity of plant polysaccharides, and improved the antioxidant and anti-tumor properties, anti-inflammatory, hypoglycemic, hypolipidemic and other biological activities of plant polysaccharides. In the future, in-depth research can be carried out in the development of simple and environmentally friendly, directional degradation, and uniform degradation methods, and the structure-activity relationship between the advanced structure of degradation products and biological activity, so as to further promote the development and application of plant polysaccharides.
Based on the necessity of plant polysaccharide degradation, the degradation methods of plant polysaccharides and the physicochemical properties and biological activities of the degradation products were reviewed as follows. The chemical degradation method was simple and easy to implement, and had low requirements for degradation equipment, but there were problems such as difficult separation of degradation products and environmental pollution; the biodegradation method had mild reaction conditions, fast degradation rate and uniform products, but there were high degradation costs, strict requirements for conditions; the synergistic use of multiple degradation methods could make up for the shortcomings of a single degradation method and improved the degradation efficiency of plant polysaccharides; degradation could significantly reduce the molecular weight and intrinsic viscosity of plant polysaccharides, and improved the antioxidant and anti-tumor properties, anti-inflammatory, hypoglycemic, hypolipidemic and other biological activities of plant polysaccharides. In the future, in-depth research can be carried out in the development of simple and environmentally friendly, directional degradation, and uniform degradation methods, and the structure-activity relationship between the advanced structure of degradation products and biological activity, so as to further promote the development and application of plant polysaccharides.
2023, 38(3)
:63-72.
doi: 10.12187/2023.03.008
Abstract:
To demonstrate the difference in moisture adsorption properties of fibers and the influence on the moisture adsorption properties of the five plant fibers (conifer, broadleaf, flax, grass and bamboo) and one regenerated fiber (Tencel), as well as the adaptability between moisture adsorption properties of fibers and coating performance of reconstituted tobacco for heated tobacco products, were studied. The results showed that the moisture adsorption properties of the six fibers were different. Tencel fiber performed the best, followed by bamboo fiber, and flax fiber performed the worst. The maximum adsorption rate and desorption rate of the fibers increased significantly with the increase of relative humidity during moisture migration. The parallel exponential dynamic model (PEK) was used to fit the moisture migration, it indicated that the progress consisted of a fast and a slow sorption procedure which occurred simultaneously. The fast procedure dominated the water migration behaviour in the sheet. As the relative humidity increased, the equilibrium moisture absorption content of the fast procedure increased and its characteristic time decreased. Meanwhile, the characteristic parameters of the slow procedure had no obvious rule with relative humidity. The micro-structure morphology, environmental conditions and other factors strongly influenced the moisture adsorption properties of fibers, the hygroscopic properties of fibers were positively correlated with the relative humidity (RH), negatively correlated with the crystallization of cellulose, while the temperature showed a weak effect on it. It was found that the reconstituted tobacco sheet showed outstanding coating performance including water and coating liquid with the application of excellent hygroscopic fibers under the condition of adding the same amount ratio during application.
To demonstrate the difference in moisture adsorption properties of fibers and the influence on the moisture adsorption properties of the five plant fibers (conifer, broadleaf, flax, grass and bamboo) and one regenerated fiber (Tencel), as well as the adaptability between moisture adsorption properties of fibers and coating performance of reconstituted tobacco for heated tobacco products, were studied. The results showed that the moisture adsorption properties of the six fibers were different. Tencel fiber performed the best, followed by bamboo fiber, and flax fiber performed the worst. The maximum adsorption rate and desorption rate of the fibers increased significantly with the increase of relative humidity during moisture migration. The parallel exponential dynamic model (PEK) was used to fit the moisture migration, it indicated that the progress consisted of a fast and a slow sorption procedure which occurred simultaneously. The fast procedure dominated the water migration behaviour in the sheet. As the relative humidity increased, the equilibrium moisture absorption content of the fast procedure increased and its characteristic time decreased. Meanwhile, the characteristic parameters of the slow procedure had no obvious rule with relative humidity. The micro-structure morphology, environmental conditions and other factors strongly influenced the moisture adsorption properties of fibers, the hygroscopic properties of fibers were positively correlated with the relative humidity (RH), negatively correlated with the crystallization of cellulose, while the temperature showed a weak effect on it. It was found that the reconstituted tobacco sheet showed outstanding coating performance including water and coating liquid with the application of excellent hygroscopic fibers under the condition of adding the same amount ratio during application.
2023, 38(3)
:73-80.
doi: 10.12187/2023.03.009
Abstract:
To investigate the influence of heating temperature on the evolution of physical and chemical structures of thermal interpreted emissions and solid phase residues in tobacco under low-oxygen atmosphere, a tubular furnace reactor was used to capture the smoke components of reconstituted tobacco leaves at different heating temperatures under low oxygen concentration and prepare solid phase residues. Representative smoke components were detected by GC-MS, and various analysis and characterization techniques were used to detect the microstructure and chemical composition of solid phase residues. The results showed that during the heating process of reconstituted tobacco leaves, the basic substances such as glycerol, propylene glycol, and nicotine were mostly directly transferred to the smoke aerosol after being heated. The release of crotonaldehyde, hydroxyacetone, isoprene, and benzene derivatives increased with increasing temperature, while the release of naphthalene decreased with increasing temperature. Phenolic ketone components such as guaiacol, cresol, phenol, 2,3-butanedione, 1-hydroxy-2-butanone, and 2 (5H)-furanone exhibited fluctuations with temperature changes; The representative volatile compounds represented by low-temperature cracking of isoprene in flue gas increase with the increase of temperature; The degree of ashing of the solid residue fiber skeleton increases with the increase of temperature; Before 370 ℃, the reconstituted tobacco leaves were mainly characterized by volatilization, distillation, and the dehydroxylation/decarboxylation of hemicellulose and cellulose. With the increase of temperature, there was an oxidation reaction in the pyrolysis process, and the proportion of more stable oxygen containing functional groups on the surface of the reconstituted tobacco leaves increased sharply.
To investigate the influence of heating temperature on the evolution of physical and chemical structures of thermal interpreted emissions and solid phase residues in tobacco under low-oxygen atmosphere, a tubular furnace reactor was used to capture the smoke components of reconstituted tobacco leaves at different heating temperatures under low oxygen concentration and prepare solid phase residues. Representative smoke components were detected by GC-MS, and various analysis and characterization techniques were used to detect the microstructure and chemical composition of solid phase residues. The results showed that during the heating process of reconstituted tobacco leaves, the basic substances such as glycerol, propylene glycol, and nicotine were mostly directly transferred to the smoke aerosol after being heated. The release of crotonaldehyde, hydroxyacetone, isoprene, and benzene derivatives increased with increasing temperature, while the release of naphthalene decreased with increasing temperature. Phenolic ketone components such as guaiacol, cresol, phenol, 2,3-butanedione, 1-hydroxy-2-butanone, and 2 (5H)-furanone exhibited fluctuations with temperature changes; The representative volatile compounds represented by low-temperature cracking of isoprene in flue gas increase with the increase of temperature; The degree of ashing of the solid residue fiber skeleton increases with the increase of temperature; Before 370 ℃, the reconstituted tobacco leaves were mainly characterized by volatilization, distillation, and the dehydroxylation/decarboxylation of hemicellulose and cellulose. With the increase of temperature, there was an oxidation reaction in the pyrolysis process, and the proportion of more stable oxygen containing functional groups on the surface of the reconstituted tobacco leaves increased sharply.
2023, 38(3)
:81-86.
doi: 10.12187/2023.03.010
Abstract:
In order to study the influence of filter ventilation of heated tobacco products on aerosol released, 1#—5# heated tobacco products samples with 0, 2, 4, 6, and 8 ventilation holes set at cavity section of filter were prepared. With an in-situ aerosol characterization method with microprobe sampling and a thermocouple temperature measurement method, the effects of ventilation on the physical properties and temperature of aerosol were investigated and analyzed. The results showed that filter ventilation changed the particle size distribution of aerosol in heated tobacco products. The particle number concentration and volume concentration of aerosol behind ventilation holes in heated tobacco products decreased with the increase of the number of ventilation holes. The reduction rate of particle volume concentration of aerosol from sample 5# was 57.4% compared with sample 1#. Ventilation reduced the count median diameter of aerosol. However, the change of count median diameter with the number of ventilation holes was not significant. The temperature of aerosol in front of and behind ventilation holes decreased with the increase of the number of ventilation holes. The aerosol temperature of sample 5# was 23.0 ℃ lower than that of sample 1#. The particle volume concentration and temperature of aerosol in front of and behind ventilation holes were higher at the central axis and lower along the radial distance.
In order to study the influence of filter ventilation of heated tobacco products on aerosol released, 1#—5# heated tobacco products samples with 0, 2, 4, 6, and 8 ventilation holes set at cavity section of filter were prepared. With an in-situ aerosol characterization method with microprobe sampling and a thermocouple temperature measurement method, the effects of ventilation on the physical properties and temperature of aerosol were investigated and analyzed. The results showed that filter ventilation changed the particle size distribution of aerosol in heated tobacco products. The particle number concentration and volume concentration of aerosol behind ventilation holes in heated tobacco products decreased with the increase of the number of ventilation holes. The reduction rate of particle volume concentration of aerosol from sample 5# was 57.4% compared with sample 1#. Ventilation reduced the count median diameter of aerosol. However, the change of count median diameter with the number of ventilation holes was not significant. The temperature of aerosol in front of and behind ventilation holes decreased with the increase of the number of ventilation holes. The aerosol temperature of sample 5# was 23.0 ℃ lower than that of sample 1#. The particle volume concentration and temperature of aerosol in front of and behind ventilation holes were higher at the central axis and lower along the radial distance.
2023, 38(3)
:87-93,111.
doi: 10.12187/2023.03.011
Abstract:
To effectively control the content of key components in cut tobacco during the heating process, the macro type tobacco high-temperature thermal conversion thermogravimetric technology was used to investigate the influence of heating temperature on the thermal weight loss process and the thermal release characteristics of key components from cut tobacco (with a moisture content of 1.5%) of heated tobacco products at temperatures of 180 ℃, 200 ℃, and 220 ℃. The results showed as the heating temperature increased, the changes in mass fraction of cut tobacco increased, the change rate of the mass fraction of cut tobacco increased, and the stability of the thermal weight loss process decreased. When the heating temperature was 200 ℃ and 220 ℃ respectively, the changes in mass fraction of each key component followed the order of nicotine, glycerol, moisture, and other components. Nicotine was practically completely released. Meanwhile, when the heating temperature was 180 ℃, the changes in mass fraction of key components of cut tobacco followed the order of nicotine, moisture, glycerol, and other components. Nicotine, glycerol, and water had higher changed in mass fraction, while other components had lower changed in mass fraction.
To effectively control the content of key components in cut tobacco during the heating process, the macro type tobacco high-temperature thermal conversion thermogravimetric technology was used to investigate the influence of heating temperature on the thermal weight loss process and the thermal release characteristics of key components from cut tobacco (with a moisture content of 1.5%) of heated tobacco products at temperatures of 180 ℃, 200 ℃, and 220 ℃. The results showed as the heating temperature increased, the changes in mass fraction of cut tobacco increased, the change rate of the mass fraction of cut tobacco increased, and the stability of the thermal weight loss process decreased. When the heating temperature was 200 ℃ and 220 ℃ respectively, the changes in mass fraction of each key component followed the order of nicotine, glycerol, moisture, and other components. Nicotine was practically completely released. Meanwhile, when the heating temperature was 180 ℃, the changes in mass fraction of key components of cut tobacco followed the order of nicotine, moisture, glycerol, and other components. Nicotine, glycerol, and water had higher changed in mass fraction, while other components had lower changed in mass fraction.
2023, 38(3)
:94-101.
doi: 10.12187/2023.03.012
Abstract:
Thermogravimetric technology was used to analyze the low temperature pyrolysis characteristics of flue-cured tobacco, burley tobacco, oriental tobacco and cigar tobacco. Meanwhile, the sensory quality of tobacco raw materials under heating conditions was evaluated, and the correlation between the pyrolysis characteristics and sensory quality was further analyzed statistically. The results showed that: under the heating condition of linear temperature-constant temperature baking, all tobacco leaves experienced four weight loss stages (dehydration and drying stage, removal stage of volatile components, decomposition stage of cellulose components and constant temperature baking stage), but there were some differences in the pyrolysis characteristic parameters of different weight loss stages. With the increase of glycerin content (0%~15%), the maximum weight loss rate and weight loss rate of all tobacco raw materials in the volatile component removal stage increased, and the maximum weight loss temperature of flue-cured tobacco increased, while that of burley tobacco, oriental tobacco and cigar tobacco decreased. When the glycerin dosage was 15%, it had the greatest effect on the weight loss rate of flue-cured tobacco at this stage, and the least effect on oriental tobacco. The total score of sensory quality of tobacco leaf samples increased with the increase of glycerin dosage. Person correlation analysis showed that the glycerin content of tobacco leaf raw materials was positively correlated with the smoke volume, aroma volume, uniformity score and total sensory quality score. There was a significant positive correlation between the maximum weight loss rate and miscellaneous gas, irritability, energy score and total sensory quality score, while the maximum weight loss rate during the decomposition stage of cellulose components had a negative correlation with aroma volume, miscellaneous gas, irritation, purity, energy score and total sensory quality score.
Thermogravimetric technology was used to analyze the low temperature pyrolysis characteristics of flue-cured tobacco, burley tobacco, oriental tobacco and cigar tobacco. Meanwhile, the sensory quality of tobacco raw materials under heating conditions was evaluated, and the correlation between the pyrolysis characteristics and sensory quality was further analyzed statistically. The results showed that: under the heating condition of linear temperature-constant temperature baking, all tobacco leaves experienced four weight loss stages (dehydration and drying stage, removal stage of volatile components, decomposition stage of cellulose components and constant temperature baking stage), but there were some differences in the pyrolysis characteristic parameters of different weight loss stages. With the increase of glycerin content (0%~15%), the maximum weight loss rate and weight loss rate of all tobacco raw materials in the volatile component removal stage increased, and the maximum weight loss temperature of flue-cured tobacco increased, while that of burley tobacco, oriental tobacco and cigar tobacco decreased. When the glycerin dosage was 15%, it had the greatest effect on the weight loss rate of flue-cured tobacco at this stage, and the least effect on oriental tobacco. The total score of sensory quality of tobacco leaf samples increased with the increase of glycerin dosage. Person correlation analysis showed that the glycerin content of tobacco leaf raw materials was positively correlated with the smoke volume, aroma volume, uniformity score and total sensory quality score. There was a significant positive correlation between the maximum weight loss rate and miscellaneous gas, irritability, energy score and total sensory quality score, while the maximum weight loss rate during the decomposition stage of cellulose components had a negative correlation with aroma volume, miscellaneous gas, irritation, purity, energy score and total sensory quality score.
2023, 38(3)
:102-111.
doi: 10.12187/2023.03.013
Abstract:
According to the normal production conditions, 13 kinds of n-alkanes were added to the core material sheet production process to prepare heated tobacco products, and a GC-MS analysis method suitable for n-alkanes in the core material, filter and mainstream smoke particulate matter of heated tobacco products was established. The transfer behavior of n-alkanes in heated tobacco products was studied by measuring the content, release and mouth-to-mouth release of n-alkanes in heated tobacco products. The results showed that: 1) The particle phase transfer rates of 13 n-alkanes in mainstream smoke were 0~53.5 %, the filter interception rate was 12.6%~50.0%, the smoke support retention rate was 0.2%~35.4%, the smoke core residue rate was 6.4%~29.3%, and the loss rate was 0.6%~81.5%; With the increase of relative molecular mass and boiling point, the transfer rate of particulate matter and the interception rate of filter in mainstream smoke of n-alkane compounds increased first and then decreased, the residual rate of cigarette core increased gradually, and the retention rate of cigarette support increased first and then stabilized. The smoke retention rate and filter rejection rate showed a good positive correlation with the boiling point of the compound within a certain range. 2) With the increase of the number of suction ports, the release amount of n-alkanes increased first and then decreased, but the order of the maximum release amount was inconsistent. The lower the boiling point of the compound, the earlier the order of the maximum release amount. 3) The coefficient of variation of the puff-by-puff release of n-alkanes ranged from 0.28 to 0.44. The coefficient of variation of the puff-by-puff release of tridecane (boiling point 235 ℃) and tetradecane (boiling point 254 ℃) was small, and the puff-by-puff release stability was good. Based on the evaluation data of the retention rate of n-alkanes in heated tobacco products, the transfer rate of particulate matter in mainstream smoke, and the stability of puff-by-puff release, the boiling point range of additives suitable for heated tobacco products was proposed to be about 250 ℃.
According to the normal production conditions, 13 kinds of n-alkanes were added to the core material sheet production process to prepare heated tobacco products, and a GC-MS analysis method suitable for n-alkanes in the core material, filter and mainstream smoke particulate matter of heated tobacco products was established. The transfer behavior of n-alkanes in heated tobacco products was studied by measuring the content, release and mouth-to-mouth release of n-alkanes in heated tobacco products. The results showed that: 1) The particle phase transfer rates of 13 n-alkanes in mainstream smoke were 0~53.5 %, the filter interception rate was 12.6%~50.0%, the smoke support retention rate was 0.2%~35.4%, the smoke core residue rate was 6.4%~29.3%, and the loss rate was 0.6%~81.5%; With the increase of relative molecular mass and boiling point, the transfer rate of particulate matter and the interception rate of filter in mainstream smoke of n-alkane compounds increased first and then decreased, the residual rate of cigarette core increased gradually, and the retention rate of cigarette support increased first and then stabilized. The smoke retention rate and filter rejection rate showed a good positive correlation with the boiling point of the compound within a certain range. 2) With the increase of the number of suction ports, the release amount of n-alkanes increased first and then decreased, but the order of the maximum release amount was inconsistent. The lower the boiling point of the compound, the earlier the order of the maximum release amount. 3) The coefficient of variation of the puff-by-puff release of n-alkanes ranged from 0.28 to 0.44. The coefficient of variation of the puff-by-puff release of tridecane (boiling point 235 ℃) and tetradecane (boiling point 254 ℃) was small, and the puff-by-puff release stability was good. Based on the evaluation data of the retention rate of n-alkanes in heated tobacco products, the transfer rate of particulate matter in mainstream smoke, and the stability of puff-by-puff release, the boiling point range of additives suitable for heated tobacco products was proposed to be about 250 ℃.
2023, 38(3)
:112-118.
doi: 10.12187/2023.03.014
Abstract:
This study preliminarily investigated the evaluation method for the impermeability of heated tobacco paper (abbreviated as heated tobacco paper) based on the static contact angle of the common liquid in heated tobacco (glycerin, water, a mixture of glycerol and water), investigated the influence of air permeability and surface treatment on the impermeability of heated tobacco paper, and explored the feasible method to replace the traditional grease resistance determination of heated cigarette paper. These results showed that with the increase of the air permeability of the heated tobacco paper, the three liquid contact angles showed a decreasing trend which meant the impermeability of heated tobacco paper decreased; the contact angles of different liquid increased with the increase of SK3 coating amount, and the contact angle of glycerol was higher than that of water and glycerol water mixture (mass ratio=1∶1), which meant the method of contact angle could distinguish the heated tobacco paper with different impermeability;there was no significant difference between propylene glycol and Kit No.3, propylene glycol ethanol mixture (mass ratio=10∶4) and Kit No.5 solution in the contact angle results, and it was feasible to quantitatively evaluate the penetration resistance of heated tobacco paper by the contact angle method and replace the traditional grease resistance method with the contact angle of an appropriate test solution by choosing propylene glycol or a specific proportion of propylene glycol ethanol mixture.
This study preliminarily investigated the evaluation method for the impermeability of heated tobacco paper (abbreviated as heated tobacco paper) based on the static contact angle of the common liquid in heated tobacco (glycerin, water, a mixture of glycerol and water), investigated the influence of air permeability and surface treatment on the impermeability of heated tobacco paper, and explored the feasible method to replace the traditional grease resistance determination of heated cigarette paper. These results showed that with the increase of the air permeability of the heated tobacco paper, the three liquid contact angles showed a decreasing trend which meant the impermeability of heated tobacco paper decreased; the contact angles of different liquid increased with the increase of SK3 coating amount, and the contact angle of glycerol was higher than that of water and glycerol water mixture (mass ratio=1∶1), which meant the method of contact angle could distinguish the heated tobacco paper with different impermeability;there was no significant difference between propylene glycol and Kit No.3, propylene glycol ethanol mixture (mass ratio=10∶4) and Kit No.5 solution in the contact angle results, and it was feasible to quantitatively evaluate the penetration resistance of heated tobacco paper by the contact angle method and replace the traditional grease resistance method with the contact angle of an appropriate test solution by choosing propylene glycol or a specific proportion of propylene glycol ethanol mixture.
2023, 38(3)
:119-126.
doi: 10.12187/2023.03.015
Abstract:
The flow analysis method based on TRIZ theory identifies the effective flow and harmful flow in the heat transfer process of the heated tobacco device, and proposes an optimization scheme for reducing energy consumption of the heated tobacco device, such as the structure optimization of the containing tube, the simplification of the airway tube, and the adjustment of the temperature distribution of the heater, and the scientificalness and practicability of the method in the energy consumption control process of iRod was verified. The results showed that: under the same taste, iRod reduced energy consumption by 11.1%, and increased the usage of 2 heated tobacco; at the same time, the temperature on the surface of the iRod was reduced by more than 3.3 ℃, the sense of touch is improved obviously.
The flow analysis method based on TRIZ theory identifies the effective flow and harmful flow in the heat transfer process of the heated tobacco device, and proposes an optimization scheme for reducing energy consumption of the heated tobacco device, such as the structure optimization of the containing tube, the simplification of the airway tube, and the adjustment of the temperature distribution of the heater, and the scientificalness and practicability of the method in the energy consumption control process of iRod was verified. The results showed that: under the same taste, iRod reduced energy consumption by 11.1%, and increased the usage of 2 heated tobacco; at the same time, the temperature on the surface of the iRod was reduced by more than 3.3 ℃, the sense of touch is improved obviously.
Journal Information
Founded in 1986， bimonthly
Administered by：The Education Department Henan Province
Sponsored by：Zhengzhou University of Light Industry
Editor-in-chief：Wei Shizhong
Executive Editor-in-Chief：Zou Lin
Subeditor：Qu Shuanghong
Edited & published by：Editorial Department of Journal of Light Industry
CN 41-1437/TS
ISSN 2096-1553
Address：136 Science Avenue, Zhengzhou City, Henan Province, China
Postal Code：450001
Tel：(086)0371-86608635
(086)0371-86608633
