2023 Vol. 38, No. 5
2023, 38(5)
:1-7.
doi: 10.12187/2023.05.001
Abstract:
Based on the advantages of large yield and rich nutrients content of typical processing waste in the brewing industry, the characteristics of nutrient content, current status of research on resource utilization and major problems faced by three typical processing waste in brewing industry, soy sauce residue, distiller's grains and vinegar residue, were reviewed as follows. The soy sauce residue, which are rich in soybean crude protein, crude fiber and other nutrients, are generally used to generate high-protein feed, organic fertilizer, soybean isoflavones and other products, but it is necessary to overcome the technical problems caused by the high salt content.The distiller's grains, rich in crude fiber, crude protein, amino acids and other nutrients, and its resource utilization mainly focuses on the fields of biological biogas, liquid fertilizers and health food, etc., while its high content of ethanol can easily result in secondary fermentation, causing acidification and corruption. Compared with soy sauce residue and distiller's grains, vinegar residue has fewer types and lower content of nutrients, which are mainly used for the development of animal feed, fertilizer and other organic products. However, its high acidity tends to inhibit microbial fermentation activity. In the future, in-depth research could be carried out in the breeding of excellent strains with high tolerant capacity, efficient separation and purification technology, microbial high-density fermentation technology coupled with advanced membrane filtration technology, etc., so as to further improve the resource conversion efficiency and high-value utilization of the typical processing waste of China's brewing industry.
Based on the advantages of large yield and rich nutrients content of typical processing waste in the brewing industry, the characteristics of nutrient content, current status of research on resource utilization and major problems faced by three typical processing waste in brewing industry, soy sauce residue, distiller's grains and vinegar residue, were reviewed as follows. The soy sauce residue, which are rich in soybean crude protein, crude fiber and other nutrients, are generally used to generate high-protein feed, organic fertilizer, soybean isoflavones and other products, but it is necessary to overcome the technical problems caused by the high salt content.The distiller's grains, rich in crude fiber, crude protein, amino acids and other nutrients, and its resource utilization mainly focuses on the fields of biological biogas, liquid fertilizers and health food, etc., while its high content of ethanol can easily result in secondary fermentation, causing acidification and corruption. Compared with soy sauce residue and distiller's grains, vinegar residue has fewer types and lower content of nutrients, which are mainly used for the development of animal feed, fertilizer and other organic products. However, its high acidity tends to inhibit microbial fermentation activity. In the future, in-depth research could be carried out in the breeding of excellent strains with high tolerant capacity, efficient separation and purification technology, microbial high-density fermentation technology coupled with advanced membrane filtration technology, etc., so as to further improve the resource conversion efficiency and high-value utilization of the typical processing waste of China's brewing industry.
2023, 38(5)
:8-16.
doi: 10.12187/2023.05.002
Abstract:
The research progress in matrix purification combined with liquid chromatography-mass spectrometry (LC-MS) method as well as their applications in determination of veterinary drugs in animal-derived foods was reviewed. Among various matrix purification methods, liquid liquid extraction (LLE), dispersed liquid liquid microextraction (DLLME), solid phase extraction (SPE), solid phase microextraction (SPME), dispersed solid phase extraction (DSPE), and magnetic solid phase extraction (MSPE) are mostly widely used in different animal derived foods such as meat, eggs, milk, and their products. However, there are still some limitations, such as weak matrix selectivity of LLE, limited applicability of DLLME, moderate purification efficiency DPSE, poor reproducibility of SPME, and time-consuming operation of SPE. In the future, the detection technology of veterinary drugs in various animal-derived foods could be further studied in terms of establishing simultaneous purification methods for various kinds of veterinary drugs, developing novel and efficient matrix-based purification materials, and enhancing convenience and automation in matrix purification process to meet the urgent needs in screening of multi-residues of veterinary drugs in animal-derived foods.
The research progress in matrix purification combined with liquid chromatography-mass spectrometry (LC-MS) method as well as their applications in determination of veterinary drugs in animal-derived foods was reviewed. Among various matrix purification methods, liquid liquid extraction (LLE), dispersed liquid liquid microextraction (DLLME), solid phase extraction (SPE), solid phase microextraction (SPME), dispersed solid phase extraction (DSPE), and magnetic solid phase extraction (MSPE) are mostly widely used in different animal derived foods such as meat, eggs, milk, and their products. However, there are still some limitations, such as weak matrix selectivity of LLE, limited applicability of DLLME, moderate purification efficiency DPSE, poor reproducibility of SPME, and time-consuming operation of SPE. In the future, the detection technology of veterinary drugs in various animal-derived foods could be further studied in terms of establishing simultaneous purification methods for various kinds of veterinary drugs, developing novel and efficient matrix-based purification materials, and enhancing convenience and automation in matrix purification process to meet the urgent needs in screening of multi-residues of veterinary drugs in animal-derived foods.
2023, 38(5)
:17-25.
doi: 10.12187/2023.05.003
Abstract:
Soybean protein isolate (SPI), konjac gum and carrageenan were used as raw materials. Konjac gum and carrageenan were mixed in different ratios (1:0, 2:1, 1:1, 1:2, 0:1, mass ratio), and then soybean protein isolate (SPI) was added to prepare heat induced emulsion gel. The influence of different proportions of konjac gum carrageenan on the gel properties of SPI emulsion gel and the related mechanism was studied. It was found that adding different proportions of konjac gum and carrageenan could significantly improve the gel properties of SPI emulsion gel. Moreover, when the ratio of konjac gum and carrageenan was 1:2, the obtained emulsion gel had the best gel properties. The average particle size of emulsion decreased from 56.59 μm to 36.84 μm and the distribution of emulsion droplets was more uniform. Compared with the control group without adding the composite system, the gel strength increased 371.98% from 122.76 g to 579.40 g, forming a more dense gel network structure. What’s more, the viscoelastic and solid properties of the emulsion gel were also greatly improved.
Soybean protein isolate (SPI), konjac gum and carrageenan were used as raw materials. Konjac gum and carrageenan were mixed in different ratios (1:0, 2:1, 1:1, 1:2, 0:1, mass ratio), and then soybean protein isolate (SPI) was added to prepare heat induced emulsion gel. The influence of different proportions of konjac gum carrageenan on the gel properties of SPI emulsion gel and the related mechanism was studied. It was found that adding different proportions of konjac gum and carrageenan could significantly improve the gel properties of SPI emulsion gel. Moreover, when the ratio of konjac gum and carrageenan was 1:2, the obtained emulsion gel had the best gel properties. The average particle size of emulsion decreased from 56.59 μm to 36.84 μm and the distribution of emulsion droplets was more uniform. Compared with the control group without adding the composite system, the gel strength increased 371.98% from 122.76 g to 579.40 g, forming a more dense gel network structure. What’s more, the viscoelastic and solid properties of the emulsion gel were also greatly improved.
2023, 38(5)
:26-35.
doi: 10.12187/2023.05.004
Abstract:
Next-generation sequencing technology was used to analyze the fungal and bacterial community structure of high-temperature Daqu from eight Baijiu companies in Maotai town, and their physicochemical indexes were measured, the two were combined for redundancy analysis (RDA). Solid-phase microextraction was used to analyze the main flavor components of high-temperature Daqu and principal component analysis (PCA) was carried out to explore the spatial characteristics of high-temperature Daqu in Maotai town. The results showed that the bacterial content was relatively high and the fungal content was relatively low from eight Baijiu companies in Maotai town. Ascomycota, Mucoromycota, and Basidiomycota were the main fungal phyla, while Firmicutes and Actinobacteria were the main bacterial phyla. The high-temperature Daqu produced by companies located closer to the center of Maotai town had higher physicochemical indexes, and richer species diversity. There were differences in the physicochemical properties of high-temperature Daqu among eight Baijiu companies. And there was a certain correlation between the physicochemical properties of high-temperature Daqu and its microbial community, but not significant (P>0.05). The high-temperature Daqu from eight Baijiu companies could not be well clustered within the small-scale range of Maotai town or at a distance from the center of Maotai town. And there were certain differences in the volatile components of high-temperature Daqu from wight Baijiu companies.
Next-generation sequencing technology was used to analyze the fungal and bacterial community structure of high-temperature Daqu from eight Baijiu companies in Maotai town, and their physicochemical indexes were measured, the two were combined for redundancy analysis (RDA). Solid-phase microextraction was used to analyze the main flavor components of high-temperature Daqu and principal component analysis (PCA) was carried out to explore the spatial characteristics of high-temperature Daqu in Maotai town. The results showed that the bacterial content was relatively high and the fungal content was relatively low from eight Baijiu companies in Maotai town. Ascomycota, Mucoromycota, and Basidiomycota were the main fungal phyla, while Firmicutes and Actinobacteria were the main bacterial phyla. The high-temperature Daqu produced by companies located closer to the center of Maotai town had higher physicochemical indexes, and richer species diversity. There were differences in the physicochemical properties of high-temperature Daqu among eight Baijiu companies. And there was a certain correlation between the physicochemical properties of high-temperature Daqu and its microbial community, but not significant (P>0.05). The high-temperature Daqu from eight Baijiu companies could not be well clustered within the small-scale range of Maotai town or at a distance from the center of Maotai town. And there were certain differences in the volatile components of high-temperature Daqu from wight Baijiu companies.
2023, 38(5)
:36-41,67.
doi: 10.12187/2023.05.005
Abstract:
Lentinan (LNT) was pre-oxidation and polysaccharide/Au nanoclusters (OLNT-AuNCs) were prepared using oxidized polysaccharides (OLNT) via microwave-assisted synthesis. Based on the quenching effect of putrescine on the electrochemiluminescence (ECL) of OLNT-AuNCs, a putrescine sensor was established and used to detect the mass concentration of putrescine in three commercially-available dry red wines. The results showed that OLNT had a good dispersion effect on AuNCs, the average particle size of AuNCs was 2.8 nm, and the spacing of lattice stripes was 0.23 nm. Under UV irradiation, AuNCs emitted red fluorescence with a peak of 612 nm; OLNT-AuNCs were excellent ECL emitters in the co-reaction reagents K2S2O8 system, putrescine had stable and specific quenching effect on this ECL system, and the decreased ECL intensity was linear with the logarithm of concentrations of putrescine in the range of 0.03~18.6 mg/L (R2=0.997 5), and the limit of detection was 9 μg/L (S/N=3). Putrescine was detected in three commercially-available dry red wines, the RSD of the determined value was less than 2%, and the recovery were 91.2%～109.3%, indicating that the sensor had good repeatability and high recovery, which could be used for the detection of putrescine in food or biological samples.
Lentinan (LNT) was pre-oxidation and polysaccharide/Au nanoclusters (OLNT-AuNCs) were prepared using oxidized polysaccharides (OLNT) via microwave-assisted synthesis. Based on the quenching effect of putrescine on the electrochemiluminescence (ECL) of OLNT-AuNCs, a putrescine sensor was established and used to detect the mass concentration of putrescine in three commercially-available dry red wines. The results showed that OLNT had a good dispersion effect on AuNCs, the average particle size of AuNCs was 2.8 nm, and the spacing of lattice stripes was 0.23 nm. Under UV irradiation, AuNCs emitted red fluorescence with a peak of 612 nm; OLNT-AuNCs were excellent ECL emitters in the co-reaction reagents K2S2O8 system, putrescine had stable and specific quenching effect on this ECL system, and the decreased ECL intensity was linear with the logarithm of concentrations of putrescine in the range of 0.03~18.6 mg/L (R2=0.997 5), and the limit of detection was 9 μg/L (S/N=3). Putrescine was detected in three commercially-available dry red wines, the RSD of the determined value was less than 2%, and the recovery were 91.2%～109.3%, indicating that the sensor had good repeatability and high recovery, which could be used for the detection of putrescine in food or biological samples.
2023, 38(5)
:42-50.
doi: 10.12187/2023.05.006
Abstract:
Bioinformatics software was used to predict the potential antigenic epitopes of G3 subunit A1b acidic polypeptide chain in glycinin. Three pairs of primers were designed and synthesized according to the overlapping amino acid sequence of A1b polypeptide chain, and the cloning vector of the target fragment was constructed. The target protein was expressed by phage display technology, and the heat-processed antibody was prepared and the destroyed antigenic epitopes were identified by ELISA. The results showed that G3A1b may contain 7 linear epitopes: 27QQN29,39LKPDNRIE46,58NNK60,114PQQKGQSSRP123,134R, 174QMPR177,184NQEQEF189. The size of the target gene matched expectations,the cloning vector was successfully constructed and the phage was successfully assembled. G3A1b-3 fragment had high antigenicity and was most obviously destroyed in the process. The results provide theoretical support for the precise positioning of the key amino acids in glycinin G3A1b.
Bioinformatics software was used to predict the potential antigenic epitopes of G3 subunit A1b acidic polypeptide chain in glycinin. Three pairs of primers were designed and synthesized according to the overlapping amino acid sequence of A1b polypeptide chain, and the cloning vector of the target fragment was constructed. The target protein was expressed by phage display technology, and the heat-processed antibody was prepared and the destroyed antigenic epitopes were identified by ELISA. The results showed that G3A1b may contain 7 linear epitopes: 27QQN29,39LKPDNRIE46,58NNK60,114PQQKGQSSRP123,134R, 174QMPR177,184NQEQEF189. The size of the target gene matched expectations,the cloning vector was successfully constructed and the phage was successfully assembled. G3A1b-3 fragment had high antigenicity and was most obviously destroyed in the process. The results provide theoretical support for the precise positioning of the key amino acids in glycinin G3A1b.
2023, 38(5)
:51-58.
doi: 10.12187/2023.05.007
Abstract:
Using whole barley flour as raw material (without adding wheat flour), barley whole-grain nutritive noodles (QN) was prepared, and the nutrient components and physicochemical properties of QN were compared with those of commercial wheat noodles (WN) and commercial barley noodles (QN-1, QN-2 and QN-3). The results showed that compared with commercial noodles, QN had significantly higher protein and dietary fiber content, and nutritional quality was significantly improved. Compared with WN,the cooking loss of QN-2, QN-3 and QN increased by 74.97%, 48.04% and 65.77%, and the water absorption increased by 2.19%,23.61% and 7.34%; The peak viscosity, attenuation value and recovery value of QN increased, and the hot paste stability decreased, therefore, QN was not suitable for long time processing; ΔH of QN decreased significantly, and starch was more gelatinized,which was related to the decrease in the ordered structure of QN starch; QN had loose internal structure and poor taste. Compared with QN-2 and QN-3, the gluten network density of QN was larger, the structure was more uniform and dense. QN could maintain the hardness and elasticity of noodles in the cooking process. Starch digestibility in vitro of 5 kinds of noodles was WN(77.50%)>QN-1(72.81%)>QN-2(72.66%)>QN-3(63.88%)>QN(54.57%). QN had lower starch digestibility and was more suitable for people with high blood sugar.
Using whole barley flour as raw material (without adding wheat flour), barley whole-grain nutritive noodles (QN) was prepared, and the nutrient components and physicochemical properties of QN were compared with those of commercial wheat noodles (WN) and commercial barley noodles (QN-1, QN-2 and QN-3). The results showed that compared with commercial noodles, QN had significantly higher protein and dietary fiber content, and nutritional quality was significantly improved. Compared with WN,the cooking loss of QN-2, QN-3 and QN increased by 74.97%, 48.04% and 65.77%, and the water absorption increased by 2.19%,23.61% and 7.34%; The peak viscosity, attenuation value and recovery value of QN increased, and the hot paste stability decreased, therefore, QN was not suitable for long time processing; ΔH of QN decreased significantly, and starch was more gelatinized,which was related to the decrease in the ordered structure of QN starch; QN had loose internal structure and poor taste. Compared with QN-2 and QN-3, the gluten network density of QN was larger, the structure was more uniform and dense. QN could maintain the hardness and elasticity of noodles in the cooking process. Starch digestibility in vitro of 5 kinds of noodles was WN(77.50%)>QN-1(72.81%)>QN-2(72.66%)>QN-3(63.88%)>QN(54.57%). QN had lower starch digestibility and was more suitable for people with high blood sugar.
2023, 38(5)
:59-67.
doi: 10.12187/2023.05.008
Abstract:
Thermogravimetry was used to reveal the pyrolysis differences of tobacco stems in different storage years in Henan, Hunan and Guizhou. The surface structure, pyrolysis characteristics and gaseous product composition of tobacco stems in different storage years in Henan were analyzed by electron microscopy and the IG-FTIR instrument,and the difference of kinetic parameters in each weight loss stage of stem in different years during the pyrolysis were compared and analyzed based on the Coats-Redfern method. The results showed that the effects of different storage years on the thermal weight-loss behavior of tobacco stems from Henan, Hunan and Guizhou were similar. The CPI value of tobacco stems stored for 1 year (1.27~1.39×10-4%·min-1·℃-2) was higher than that of tobacco stems stored for 2 and 3 years, indicating good pyrolysis characteristics; the residual rate of tobacco stems stored for 3 years was 18.18%~27.45%, with poor thermal stability.While the types of pyrolysis gas products released by tobacco stems in different storage years in Henan were similar, and the maximum gas product release rate was shown as follows: tobacco stems stored for 3 years> those stored for 2 years> those stored for 1 year, and the integrity of the surface structure of tobacco stem was poor after 3 years storage, the main weight loss stages during the thermal decomposition of different storage years' tobacco stem was mainly controlled by a 1.5-order chemical reaction model.
Thermogravimetry was used to reveal the pyrolysis differences of tobacco stems in different storage years in Henan, Hunan and Guizhou. The surface structure, pyrolysis characteristics and gaseous product composition of tobacco stems in different storage years in Henan were analyzed by electron microscopy and the IG-FTIR instrument,and the difference of kinetic parameters in each weight loss stage of stem in different years during the pyrolysis were compared and analyzed based on the Coats-Redfern method. The results showed that the effects of different storage years on the thermal weight-loss behavior of tobacco stems from Henan, Hunan and Guizhou were similar. The CPI value of tobacco stems stored for 1 year (1.27~1.39×10-4%·min-1·℃-2) was higher than that of tobacco stems stored for 2 and 3 years, indicating good pyrolysis characteristics; the residual rate of tobacco stems stored for 3 years was 18.18%~27.45%, with poor thermal stability.While the types of pyrolysis gas products released by tobacco stems in different storage years in Henan were similar, and the maximum gas product release rate was shown as follows: tobacco stems stored for 3 years> those stored for 2 years> those stored for 1 year, and the integrity of the surface structure of tobacco stem was poor after 3 years storage, the main weight loss stages during the thermal decomposition of different storage years' tobacco stem was mainly controlled by a 1.5-order chemical reaction model.
2023, 38(5)
:68-73,82.
doi: 10.12187/2023.05.009
Abstract:
By extracting and measuring[BP)]Selecting parameters that could comprehensively characterize the filling state of cut tobacco, the influence of the filling state of cut tobacco [BP(](filling value, filling amount, filling density) [BP)]parameters on the quality of cigarette making (suction resistance, hardness, total ventilation rate) and the ash integrity of cigarette was investigated. The results showed that the filling value, filling amount, and filling density of the cut tobacco inside the cigarette could comprehensively reflect the filling state of the cut tobacco, where the filling density could be characterized by the midpoint density, average density, density index, and density gradient of the cigarette.[BP(]; 2) The degree of tightness is the main factor affecting the filling state of cut tobacco. 3)[BP)] The filling state of cut tobacco could significantly affect the suction resistance, hardness, and total ventilation rate of cigarettes, with determination coefficients of 0.781, 0.576 and 0.672, respectively. The suction resistance, total ventilation rate, cut tobacco filling value, and filling amount had significant impact on the comprehensive ash integrity of cigarette, with a determination coefficient of 0.391.
By extracting and measuring[BP)]Selecting parameters that could comprehensively characterize the filling state of cut tobacco, the influence of the filling state of cut tobacco [BP(](filling value, filling amount, filling density) [BP)]parameters on the quality of cigarette making (suction resistance, hardness, total ventilation rate) and the ash integrity of cigarette was investigated. The results showed that the filling value, filling amount, and filling density of the cut tobacco inside the cigarette could comprehensively reflect the filling state of the cut tobacco, where the filling density could be characterized by the midpoint density, average density, density index, and density gradient of the cigarette.[BP(]; 2) The degree of tightness is the main factor affecting the filling state of cut tobacco. 3)[BP)] The filling state of cut tobacco could significantly affect the suction resistance, hardness, and total ventilation rate of cigarettes, with determination coefficients of 0.781, 0.576 and 0.672, respectively. The suction resistance, total ventilation rate, cut tobacco filling value, and filling amount had significant impact on the comprehensive ash integrity of cigarette, with a determination coefficient of 0.391.
2023, 38(5)
:74-82.
doi: 10.12187/2023.05.010
Abstract:
In order to understand the quality difference between Canada and Yunnan KRK26 tobacco leaves, the differences of aroma components were analyzed and compared by main component analysis and orthogonal partial least squares discriminant analysis (OPLS-DA). Test data showed that a total of 117 aroma components belonging to 9 classes were detected in the leaves, of which 110 components were shared by both, while 114 components were present in Canada tobacco leaves and 113 components in KRK26 tobacco leaves. Totally 65 differential aroma components were identified between the two tobacco leaves, accounting for 50.6% of the total aroma components common to them. Furthermore, 22 differential components had higher content (33.8%) in Canada tobacco leaves than that in KRK26 tobacco leaves, whereas 43 metabolites (66.2%) showed the opposite result which are mainly carotenoid degradation products. Compared with KRK26 tobacco leaves, Canada tobacco leaves had higher content of semi-volatile fatty acids and sesquiterpenes, while the content of carotenoid degradation products such as megastigmatrienones, damascenon and dihydrodamascenon was relatively low, which might be one of the factors causing the different sensory aroma characteristics of the two.
In order to understand the quality difference between Canada and Yunnan KRK26 tobacco leaves, the differences of aroma components were analyzed and compared by main component analysis and orthogonal partial least squares discriminant analysis (OPLS-DA). Test data showed that a total of 117 aroma components belonging to 9 classes were detected in the leaves, of which 110 components were shared by both, while 114 components were present in Canada tobacco leaves and 113 components in KRK26 tobacco leaves. Totally 65 differential aroma components were identified between the two tobacco leaves, accounting for 50.6% of the total aroma components common to them. Furthermore, 22 differential components had higher content (33.8%) in Canada tobacco leaves than that in KRK26 tobacco leaves, whereas 43 metabolites (66.2%) showed the opposite result which are mainly carotenoid degradation products. Compared with KRK26 tobacco leaves, Canada tobacco leaves had higher content of semi-volatile fatty acids and sesquiterpenes, while the content of carotenoid degradation products such as megastigmatrienones, damascenon and dihydrodamascenon was relatively low, which might be one of the factors causing the different sensory aroma characteristics of the two.
2023, 38(5)
:83-87.
doi: 10.12187/2023.05.011
Abstract:
Investigating the quantitative analysis of two stereoisomeric compounds, specifically (6R, 9R)-3-oxo-α-ionol-β-D-glucopyranoside (rrOIPG) and (6R, 9S)-3-oxo-α-ionol-β-D-pyranoside (rsOIPG), megastigmatrienone precursors of the prominent aroma components in tobacco leaves, represented the core focus of this study. A meticulously-devised methodology combining ultrasound-assisted extraction with ultra-high-performance liquid chromatography (UHPLC) was deployed to ascertain the precise quantification of rrOIPG and rsOIPG. This robust analytical approach was judiciously employed to elucidate the geographical distribution patterns of these stereoisomers within tobacco leaves sourced from seven diverse global regions. The results revealed the compelling linear response characteristics of rrOIPG and rsOIPG, scanninged concentration ranges of 25.85 to 258.50 μg/mL (R2=0.999 1) and 6.28 to 62.75 μg/mL (R2=0.999 0), respectively. Exceptionally low detection limits of 2.5 μg/mL for rrOIPG and 2.9 μg/mL for rsOIPG underscore the method's inherent precision. The analysis exhibited superb stability and reproducibility, epitomized by recovery rates of 83.94% for rrOIPG and 105.90% for rsOIPG, and RSDs were 1.22% and 1.93%, respectively. According to the content distribution of rrOIPG and rsOIPG, the tobacco leaves from domestic and foreign origins could be well distinguished, and the content of rsOIPG configuration in foreign origins was significantly higher than that in domestic origins. In terms of the distribution of the two configurations, the content of rrOIPG configuration was higher than that of rsOIPG configuration. The developed technique exhibits high feasibility and streamlined pretreatment processes, making it well-suitable for the quantitative analysis of rrOIPG and rsOIPG in tobacco leaves.
Investigating the quantitative analysis of two stereoisomeric compounds, specifically (6R, 9R)-3-oxo-α-ionol-β-D-glucopyranoside (rrOIPG) and (6R, 9S)-3-oxo-α-ionol-β-D-pyranoside (rsOIPG), megastigmatrienone precursors of the prominent aroma components in tobacco leaves, represented the core focus of this study. A meticulously-devised methodology combining ultrasound-assisted extraction with ultra-high-performance liquid chromatography (UHPLC) was deployed to ascertain the precise quantification of rrOIPG and rsOIPG. This robust analytical approach was judiciously employed to elucidate the geographical distribution patterns of these stereoisomers within tobacco leaves sourced from seven diverse global regions. The results revealed the compelling linear response characteristics of rrOIPG and rsOIPG, scanninged concentration ranges of 25.85 to 258.50 μg/mL (R2=0.999 1) and 6.28 to 62.75 μg/mL (R2=0.999 0), respectively. Exceptionally low detection limits of 2.5 μg/mL for rrOIPG and 2.9 μg/mL for rsOIPG underscore the method's inherent precision. The analysis exhibited superb stability and reproducibility, epitomized by recovery rates of 83.94% for rrOIPG and 105.90% for rsOIPG, and RSDs were 1.22% and 1.93%, respectively. According to the content distribution of rrOIPG and rsOIPG, the tobacco leaves from domestic and foreign origins could be well distinguished, and the content of rsOIPG configuration in foreign origins was significantly higher than that in domestic origins. In terms of the distribution of the two configurations, the content of rrOIPG configuration was higher than that of rsOIPG configuration. The developed technique exhibits high feasibility and streamlined pretreatment processes, making it well-suitable for the quantitative analysis of rrOIPG and rsOIPG in tobacco leaves.
2023, 38(5)
:88-95.
doi: 10.12187/2023.05.012
Abstract:
Polyacrylamide (PAM)-glycerol (Gly)-lithium chloride (LiCl) hydrogel was prepared by salt solution immersion method, using PAM as the hydrogel matrix, Gly as the moisturizing factor and LiCl as the water absorption factor. The structure and performance of the hydrogel were characterized by scanning electron microscope, energy dispersive spectrometer, X-ray photoelectron spectrometer, Fourier infrared spectrometer, etc. Meanwhile, the effect of its application in a portable cigar moisturizing bag on the regulation of micro environment humidity was explored. The results showed that the PAM-Gly-LiCl hydrogel possessed excellent transparency and mechanical properties, with light transmittance of 90%, the maximum compression strain of 41%, compression strength of 1.1 MPa, elongation breaking rate of 1100% and breaking strength of 0.25 MPa. The hydrogel also displayed excellent water retention and humidity control performance. Owing to a high proportion of combined water, it could stably realize the humidity control process under different humidity environmental conditions. The humidity control range was 25%~95% of the relative humidity and kept for 500 h. The hydrogel could be applied to design as a portable cigar moisturizing bag. It could quickly sense changes in environmental humidity and make intelligent responses, stabilizing the microenvironment relative humidity inside the bag at around 65% and maintaining it for more than a week.
Polyacrylamide (PAM)-glycerol (Gly)-lithium chloride (LiCl) hydrogel was prepared by salt solution immersion method, using PAM as the hydrogel matrix, Gly as the moisturizing factor and LiCl as the water absorption factor. The structure and performance of the hydrogel were characterized by scanning electron microscope, energy dispersive spectrometer, X-ray photoelectron spectrometer, Fourier infrared spectrometer, etc. Meanwhile, the effect of its application in a portable cigar moisturizing bag on the regulation of micro environment humidity was explored. The results showed that the PAM-Gly-LiCl hydrogel possessed excellent transparency and mechanical properties, with light transmittance of 90%, the maximum compression strain of 41%, compression strength of 1.1 MPa, elongation breaking rate of 1100% and breaking strength of 0.25 MPa. The hydrogel also displayed excellent water retention and humidity control performance. Owing to a high proportion of combined water, it could stably realize the humidity control process under different humidity environmental conditions. The humidity control range was 25%~95% of the relative humidity and kept for 500 h. The hydrogel could be applied to design as a portable cigar moisturizing bag. It could quickly sense changes in environmental humidity and make intelligent responses, stabilizing the microenvironment relative humidity inside the bag at around 65% and maintaining it for more than a week.
2023, 38(5)
:96-103.
doi: 10.12187/2023.05.013
Abstract:
In order to study the distribution of heat and moisture environment inside the moistening cylinder, a three-dimensional moistening cylinder model with real proportion was constructed. The three-dimensional heat and mass transfer process inside the moistening cylinder was numerically simulated by computational fluid dynamics (CFD) method, and the spray angle and cylinder inclination angle were optimized according to temperature and moisture content. The results showed that the simulated values were in good agreement with the experimental values, and the average relative error of temperature was 0.6%. The established CFD model was real and effective. The temperature of the gas phase in the axial direction changes in stages. The temperature in the first half increased rapidly, and the temperature in the second half was stable at about 341.0 K. The continuous mass and heat transfer of atomized water and water vapor to tobacco leaves gradually increased the temperature and moisture content of tobacco leaves in the axial direction. The temperature of tobacco leaves at the final discharge port reached 326.3 K, and the moisture content reached 17.21%. Through further research, the optimization suggestions for the process conditions of the moistening cylinder are put forward: the inclination angle of the cylinder should be selected as 3°, and the spray angle should be selected as 45°.
In order to study the distribution of heat and moisture environment inside the moistening cylinder, a three-dimensional moistening cylinder model with real proportion was constructed. The three-dimensional heat and mass transfer process inside the moistening cylinder was numerically simulated by computational fluid dynamics (CFD) method, and the spray angle and cylinder inclination angle were optimized according to temperature and moisture content. The results showed that the simulated values were in good agreement with the experimental values, and the average relative error of temperature was 0.6%. The established CFD model was real and effective. The temperature of the gas phase in the axial direction changes in stages. The temperature in the first half increased rapidly, and the temperature in the second half was stable at about 341.0 K. The continuous mass and heat transfer of atomized water and water vapor to tobacco leaves gradually increased the temperature and moisture content of tobacco leaves in the axial direction. The temperature of tobacco leaves at the final discharge port reached 326.3 K, and the moisture content reached 17.21%. Through further research, the optimization suggestions for the process conditions of the moistening cylinder are put forward: the inclination angle of the cylinder should be selected as 3°, and the spray angle should be selected as 45°.
2023, 38(5)
:104-111.
doi: 10.12187/2023.05.014
Abstract:
In order to improve the quality of tobacco silk, the processing parameters of tobacco silk were optimized by using BP Neural Network (BPNN), taking the physical properties of tobacco silk, the physical properties of cigarettes and the chemical composition of cigarettes as quality control indicators. The BPNN optimization results were compared with the orthogonal test results, and the optimized parameters were verified. The results showed that the prediction results of the established BPNN model had high reliability and accuracy, and the optimal silk-making processing parameters combination predicted by BPNN was unique and accurate. There were differences in the parameter settings of steam flow and hot air temperature for the optimal combination of tobacco silk-making process parameters obtained by the orthogonal test method. After the parameters of the tobacco silk-making processing parameters were optimized, the whole cut rate and filling value of tobacco silk had been improved, the broken cut rate had been reduced, the standard deviation of single cigarette weight and cigarette suction resistance had decreased, and the CO, tar, and nicotine releases had been reduced, and the overall optimization effect was obvious. BPNN accurately predicted the optimal parameters of tobacco silkmaking, which avoided misjudgment, improved processing efficiency, and reduced time cost and resource waste.
In order to improve the quality of tobacco silk, the processing parameters of tobacco silk were optimized by using BP Neural Network (BPNN), taking the physical properties of tobacco silk, the physical properties of cigarettes and the chemical composition of cigarettes as quality control indicators. The BPNN optimization results were compared with the orthogonal test results, and the optimized parameters were verified. The results showed that the prediction results of the established BPNN model had high reliability and accuracy, and the optimal silk-making processing parameters combination predicted by BPNN was unique and accurate. There were differences in the parameter settings of steam flow and hot air temperature for the optimal combination of tobacco silk-making process parameters obtained by the orthogonal test method. After the parameters of the tobacco silk-making processing parameters were optimized, the whole cut rate and filling value of tobacco silk had been improved, the broken cut rate had been reduced, the standard deviation of single cigarette weight and cigarette suction resistance had decreased, and the CO, tar, and nicotine releases had been reduced, and the overall optimization effect was obvious. BPNN accurately predicted the optimal parameters of tobacco silkmaking, which avoided misjudgment, improved processing efficiency, and reduced time cost and resource waste.
2023, 38(5)
:112-118.
doi: 10.12187/2023.05.015
Abstract:
Based on the significant effects of enzyme treatment on tobacco and its products, the research achievements of enzyme treatment in tobacco quality improvement, aroma production, and harm reduction in recent years were reviewed as follows. The weak links and problems in the research of biological enzymes were analyzed. Significant progress had been made in the research of enzymatic degradation of starch and pectin in tobacco leaves, with composite enzymes being more effective than single enzymes. The combination of laccase and protease had a better effect on treating tobacco stems than single. At the same time, treatments with acid, alkali, and steam explosion could significantly improve the enzymatic hydrolysis effect. In the process of reconstituted tobacco leaf concentrate using raw materials for tobacco thin slice preparation, biological enzymes were more effective, with advantages such as short processing time, high efficiency, and significant effects. In terms of aroma production, it was mainly achieved by producing substances that could participate in the Maillard reaction or catalyze the production of aroma precursors. In terms of harm reduction of cigarettes, it was mainly achieved by reducing the content of tobacco specific Nitrosamine and smoke free radicals and other harmful substances. In the future, in-depth research can be carried out from the aspects of structural characterization and characteristics of tobacco biomacromolecules, creation of tobacco enzyme preparations and analysis of catalytic mechanism, so as to further promote the research and application of biological enzymes in tobacco aroma enhancement, quality improvement and harm reduction.
Based on the significant effects of enzyme treatment on tobacco and its products, the research achievements of enzyme treatment in tobacco quality improvement, aroma production, and harm reduction in recent years were reviewed as follows. The weak links and problems in the research of biological enzymes were analyzed. Significant progress had been made in the research of enzymatic degradation of starch and pectin in tobacco leaves, with composite enzymes being more effective than single enzymes. The combination of laccase and protease had a better effect on treating tobacco stems than single. At the same time, treatments with acid, alkali, and steam explosion could significantly improve the enzymatic hydrolysis effect. In the process of reconstituted tobacco leaf concentrate using raw materials for tobacco thin slice preparation, biological enzymes were more effective, with advantages such as short processing time, high efficiency, and significant effects. In terms of aroma production, it was mainly achieved by producing substances that could participate in the Maillard reaction or catalyze the production of aroma precursors. In terms of harm reduction of cigarettes, it was mainly achieved by reducing the content of tobacco specific Nitrosamine and smoke free radicals and other harmful substances. In the future, in-depth research can be carried out from the aspects of structural characterization and characteristics of tobacco biomacromolecules, creation of tobacco enzyme preparations and analysis of catalytic mechanism, so as to further promote the research and application of biological enzymes in tobacco aroma enhancement, quality improvement and harm reduction.
2023, 38(5)
:119-126.
doi: 10.12187/2023.05.016
Abstract:
Platinum nanoparticles (PtNPs) were synthesized by one-step green method using Eucommia ulmoides Oliver leaf extract as reducer and stabilizer. The effects of reaction conditions on the color and concentration of PtNPs were analyzed by single factor test, and the effect of PtNPs on tyrosinase activity was studied. The results showed that the color and yield of PtNPs could be controlled by changing the reaction conditions in a certain range. The suitable reaction conditions of each factor were reaction time of 60 min, reaction temperature of 90 ℃, chloroplatinic acid concentration of 3.5 mmol/L, Eucommia ulmoides Oliver leaf extract concentration of 10.0 mg/mL. Under these conditions, the average size of prepared PtNPs was (2.27±0.65)nm, with face-centered cubic structure and dispersed distribution. PtNPs had a strong inhibitory effect on tyrosinase activity in vitro, IC50 value was (6.98±0.76) μg/mL, which significantly reduced tyrosinase activity and melanin content induced by UVB in A375 cells, and could achieve the effect of whitening skin.
Platinum nanoparticles (PtNPs) were synthesized by one-step green method using Eucommia ulmoides Oliver leaf extract as reducer and stabilizer. The effects of reaction conditions on the color and concentration of PtNPs were analyzed by single factor test, and the effect of PtNPs on tyrosinase activity was studied. The results showed that the color and yield of PtNPs could be controlled by changing the reaction conditions in a certain range. The suitable reaction conditions of each factor were reaction time of 60 min, reaction temperature of 90 ℃, chloroplatinic acid concentration of 3.5 mmol/L, Eucommia ulmoides Oliver leaf extract concentration of 10.0 mg/mL. Under these conditions, the average size of prepared PtNPs was (2.27±0.65)nm, with face-centered cubic structure and dispersed distribution. PtNPs had a strong inhibitory effect on tyrosinase activity in vitro, IC50 value was (6.98±0.76) μg/mL, which significantly reduced tyrosinase activity and melanin content induced by UVB in A375 cells, and could achieve the effect of whitening skin.
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
Deputy Editor-in-Chief：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
