2024 Vol. 39, No. 1
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2024, 39(1)
:1-11.
doi: 10.12187/2024.01.001
Abstract:
The utilization of lipase in synthesis structured lipids (SLs) from natural oils confers additional health properties and effectively enhances their value-added potential. This paper provided a comprehensive review of recent studies on the enzymatic preparation of SLs, summarizing the advancements in structural design and immobilized enzyme engineering technology to improve the efficiency of their synthesis by enzymatic approaches. The sn-1,3 regiospecific lipase enabled the precise synthesis of SLs, while employing stepwise variable temperature reactions, supercritical fluid reactions, vacuum reactions, and ultrasonic-assisted methods could inhibit the acyl migration effects and further enhance product yield. Furthermore, structural design could enhance the catalytic efficiency, stability, and substrate specificity of lipases to elevate the efficiency and yield in enzymatic synthesis of SLs. Immobilized enzyme technology could enhance enzyme reactivity and stability while reducing the costs of enzymatic synthesis of SLs. In the future, the high-performance enzymes should be developed by combining structural modification and novel immobilization technology on the basis of the clearer understanding of their structure-function characteristics. These insights would contribute to innovation and advancement in efficient and precise enzymatic synthesis processes for SLs.
The utilization of lipase in synthesis structured lipids (SLs) from natural oils confers additional health properties and effectively enhances their value-added potential. This paper provided a comprehensive review of recent studies on the enzymatic preparation of SLs, summarizing the advancements in structural design and immobilized enzyme engineering technology to improve the efficiency of their synthesis by enzymatic approaches. The sn-1,3 regiospecific lipase enabled the precise synthesis of SLs, while employing stepwise variable temperature reactions, supercritical fluid reactions, vacuum reactions, and ultrasonic-assisted methods could inhibit the acyl migration effects and further enhance product yield. Furthermore, structural design could enhance the catalytic efficiency, stability, and substrate specificity of lipases to elevate the efficiency and yield in enzymatic synthesis of SLs. Immobilized enzyme technology could enhance enzyme reactivity and stability while reducing the costs of enzymatic synthesis of SLs. In the future, the high-performance enzymes should be developed by combining structural modification and novel immobilization technology on the basis of the clearer understanding of their structure-function characteristics. These insights would contribute to innovation and advancement in efficient and precise enzymatic synthesis processes for SLs.
2024, 39(1)
:12-21.
doi: 10.12187/2024.01.002
Abstract:
The walnut oil oleogels prepared by beeswax and monoglyceride was used as the research object and the effects of ultrasound treatment before or after complex oleogelators melting on the structure and properties of the walnut oli oleogels were explored. The research results indicated that when the mass ratio of beeswax to monoglyceride was 3∶7, the formed walnut oil oleogels had an oil bonding capacity (OBC) of over 95% and a smooth and stable surface morphology. All walnut oleogels showed solid-like elastic properties within a certain shear strain range, and the walnut oil oleogels prepared with 100 W-30 s parameters had the strongest mechanical properties. Ultrasound treatment could improve the crystal structure of walnut oil oleogels, produce more compact and fine crystal morphology, and effectively enhance OBC and thermal stability of walnut oil oleogels. The oleofoams obtained by whipping the oleogels exhibited excellent decorative performance, and ultrasound treatment could significantly increase the overrun of the walnut oil oleogels. In sum, ultrasound treatment could improve the structure and properties of walnut oil oleogel, and make it a good substitute for margarine.
The walnut oil oleogels prepared by beeswax and monoglyceride was used as the research object and the effects of ultrasound treatment before or after complex oleogelators melting on the structure and properties of the walnut oli oleogels were explored. The research results indicated that when the mass ratio of beeswax to monoglyceride was 3∶7, the formed walnut oil oleogels had an oil bonding capacity (OBC) of over 95% and a smooth and stable surface morphology. All walnut oleogels showed solid-like elastic properties within a certain shear strain range, and the walnut oil oleogels prepared with 100 W-30 s parameters had the strongest mechanical properties. Ultrasound treatment could improve the crystal structure of walnut oil oleogels, produce more compact and fine crystal morphology, and effectively enhance OBC and thermal stability of walnut oil oleogels. The oleofoams obtained by whipping the oleogels exhibited excellent decorative performance, and ultrasound treatment could significantly increase the overrun of the walnut oil oleogels. In sum, ultrasound treatment could improve the structure and properties of walnut oil oleogel, and make it a good substitute for margarine.
2024, 39(1)
:22-29.
doi: 10.12187/2024.01.003
Abstract:
The effects of microwave pretreatment time (0~12 min) on the physical properties of black sesame seed and whole seed milk stability were investigated. The results showed that microwave pretreatment induced the volume expansion of black sesame seed, and uneven outer seed coat, which was further ruptured when the microwave pretreatment further reached 12 min. The hardness, elasticity, adhesion and resilience values of black sesame seed were significantly reduced upon microwave pretreatment (P<0.05), achieving the minimum values when the microwave pretreatment extended for 9 min. With the gradual prolongation of microwave pretreatment time, the average particle size of black sesame milk increased from 1.21 μm to 1.52 μm (P<0.05), and the zeta potential values decreased from -26.90 mV to -31.91 mV (P<0.05), accompanied by the obvious improvement of physical stability. In particular the black sesame milk exhibited an optimal physical stability when microwave pretreatment increased for 9 min as manifested by the obvious decrease in the curve slope of the Turbiscan Stability Index (TSI) values, and a slight change in the bottom and top of the ΔBS curves. Microwave pretreatment, particularly for 9 min, enhanced the elasticity behavior and weakened the fluidity of black sesame seed milk in the static system, decreased the apparent viscosity, and increased the viscoelasticity in dynamic system. Microwave pretreatment caused an obvious increase in the particle size of emulsion droplets, and adecrease in the lamellar porous storage proteins in bulk aqueous phase of black sesame seed milk, suggesting the preferential participation in the reproduction of emulsion droplets. Therefore, suitable microwave pretreatment could remodel the physical properties of black sesame seed and physical stability of whole seed milk, thereby broadening their application scenarios.
The effects of microwave pretreatment time (0~12 min) on the physical properties of black sesame seed and whole seed milk stability were investigated. The results showed that microwave pretreatment induced the volume expansion of black sesame seed, and uneven outer seed coat, which was further ruptured when the microwave pretreatment further reached 12 min. The hardness, elasticity, adhesion and resilience values of black sesame seed were significantly reduced upon microwave pretreatment (P<0.05), achieving the minimum values when the microwave pretreatment extended for 9 min. With the gradual prolongation of microwave pretreatment time, the average particle size of black sesame milk increased from 1.21 μm to 1.52 μm (P<0.05), and the zeta potential values decreased from -26.90 mV to -31.91 mV (P<0.05), accompanied by the obvious improvement of physical stability. In particular the black sesame milk exhibited an optimal physical stability when microwave pretreatment increased for 9 min as manifested by the obvious decrease in the curve slope of the Turbiscan Stability Index (TSI) values, and a slight change in the bottom and top of the ΔBS curves. Microwave pretreatment, particularly for 9 min, enhanced the elasticity behavior and weakened the fluidity of black sesame seed milk in the static system, decreased the apparent viscosity, and increased the viscoelasticity in dynamic system. Microwave pretreatment caused an obvious increase in the particle size of emulsion droplets, and adecrease in the lamellar porous storage proteins in bulk aqueous phase of black sesame seed milk, suggesting the preferential participation in the reproduction of emulsion droplets. Therefore, suitable microwave pretreatment could remodel the physical properties of black sesame seed and physical stability of whole seed milk, thereby broadening their application scenarios.
2024, 39(1)
:30-37.
doi: 10.12187/2024.01.004
Abstract:
The commercial sesame oil was selected as the research subject and its volatile flavor components was extracted through solvent-assisted flavor evaporation (SAFE). Then, the aroma substances of the sesame oil were semi-quantitatively analyzed based on triple quadrupole gas chromatography-mass spectrometry. Finally, the relative odor activity values (ROAV) were combined to analyze the terms of volatile flavor contributions. The results showed that a total of 107 volatile flavor components were identified in sesame oil, of which 35 substances were seem as contributed flavor (ROAV≥0.01), including 4 sulfides, 5 phenols, 10 pyrazines, 4 furans, 3 aldehydes, 4 thiazoles, 2 pyrroles, 2 thiophenes, and 1 indole. They provided "cabbage" "fishy" "sulfur" "smoky" "popcorn" "oil" and "roasted sesame". In particular, compounds 14 flavor components with ROAV≥0.10 were determined as key flavor components, such as acetyl pyrazine, 2-furanmethanol, 2,3-dimethyl-pyrazine, 2,3,5-trimethylpyrazine, dimethyl disulfide, dimethyl trisulphide, methyl furfuryl disulfide, methyl thiolacetate, 4-vinyl-2-methoxyphenol, 2-methoxyphenol, hexanal, 2-ethyl-6-methyl-pyrazine, 2-methyl-3-furanothiol and 3-ethyl-2,5-dimethyl-pyrazine. Using this method to determine the key volatile flavor components of sesame oil, not only could expand the flavor database of sesame oil, but also could provide an important material basis for evaluating and regulating the flavor quality of sesame oil.
The commercial sesame oil was selected as the research subject and its volatile flavor components was extracted through solvent-assisted flavor evaporation (SAFE). Then, the aroma substances of the sesame oil were semi-quantitatively analyzed based on triple quadrupole gas chromatography-mass spectrometry. Finally, the relative odor activity values (ROAV) were combined to analyze the terms of volatile flavor contributions. The results showed that a total of 107 volatile flavor components were identified in sesame oil, of which 35 substances were seem as contributed flavor (ROAV≥0.01), including 4 sulfides, 5 phenols, 10 pyrazines, 4 furans, 3 aldehydes, 4 thiazoles, 2 pyrroles, 2 thiophenes, and 1 indole. They provided "cabbage" "fishy" "sulfur" "smoky" "popcorn" "oil" and "roasted sesame". In particular, compounds 14 flavor components with ROAV≥0.10 were determined as key flavor components, such as acetyl pyrazine, 2-furanmethanol, 2,3-dimethyl-pyrazine, 2,3,5-trimethylpyrazine, dimethyl disulfide, dimethyl trisulphide, methyl furfuryl disulfide, methyl thiolacetate, 4-vinyl-2-methoxyphenol, 2-methoxyphenol, hexanal, 2-ethyl-6-methyl-pyrazine, 2-methyl-3-furanothiol and 3-ethyl-2,5-dimethyl-pyrazine. Using this method to determine the key volatile flavor components of sesame oil, not only could expand the flavor database of sesame oil, but also could provide an important material basis for evaluating and regulating the flavor quality of sesame oil.
2024, 39(1)
:38-47,56.
doi: 10.12187/2024.01.005
Abstract:
With diacylglycerol (DAG) and long-medium-long (LML) structured lipids as research object and soybean oil was used as the control, the physicochemical properties, thermodynamic properties and frying application properties of 50% DAG, 90% DAG were studied. The results showed that the viscosity, density, acid value (AV) and peroxide value (POV) of 50% DAG, 90% DAG and LML structured lipids were consistent with soybean oil, and the aniside value (AnV)of the three lipids were all higher than that of soybean oil. In addition, the triglyceride composition and fatty acid composition of the three oil in the experiments were only different because of the structure change and the middle chain fatty acids. Both the —OH in 50% DAG and 90% DAG, and the medium chain fatty acids in LML structured lipids would decrease the initial weight loss temperature, and the melting curves of the 50% DAG and 90% DAG would have a large temperature span. The differences of 50% DAG, 90% DAG and LML structured lipids in 3470 cm-1, 1400~1100 cm-1 and 722 cm-1 were caused by structural change. After continuous frying at high temperature, the acid value, peroxide value, chroma, moisture content, anisidine value of 50% DAG, 90% DAG and LML structure lipids and the texture of potatoes after frying with different fats did not change significantly. The AV, POV, chroma, moisture content, AnV and glyceride composition of 50% DAG, 90% DAG and LML structured lipids, and the texture properties of potato chips after high-temperature continuous frying demonstrated good stability. In summary, 50% DAG, 90% DAG, and LML structured lipids maintained good stability during high-temperature continuous frying, meeting the national frying oil standards, and could be used as daily frying oil.
With diacylglycerol (DAG) and long-medium-long (LML) structured lipids as research object and soybean oil was used as the control, the physicochemical properties, thermodynamic properties and frying application properties of 50% DAG, 90% DAG were studied. The results showed that the viscosity, density, acid value (AV) and peroxide value (POV) of 50% DAG, 90% DAG and LML structured lipids were consistent with soybean oil, and the aniside value (AnV)of the three lipids were all higher than that of soybean oil. In addition, the triglyceride composition and fatty acid composition of the three oil in the experiments were only different because of the structure change and the middle chain fatty acids. Both the —OH in 50% DAG and 90% DAG, and the medium chain fatty acids in LML structured lipids would decrease the initial weight loss temperature, and the melting curves of the 50% DAG and 90% DAG would have a large temperature span. The differences of 50% DAG, 90% DAG and LML structured lipids in 3470 cm-1, 1400~1100 cm-1 and 722 cm-1 were caused by structural change. After continuous frying at high temperature, the acid value, peroxide value, chroma, moisture content, anisidine value of 50% DAG, 90% DAG and LML structure lipids and the texture of potatoes after frying with different fats did not change significantly. The AV, POV, chroma, moisture content, AnV and glyceride composition of 50% DAG, 90% DAG and LML structured lipids, and the texture properties of potato chips after high-temperature continuous frying demonstrated good stability. In summary, 50% DAG, 90% DAG, and LML structured lipids maintained good stability during high-temperature continuous frying, meeting the national frying oil standards, and could be used as daily frying oil.
2024, 39(1)
:48-56.
doi: 10.12187/2024.01.006
Abstract:
The adsorptive removal effects of four adsorbents (wood-activated carbon powder, coconut shell-activated carbon powder, coal-activated carbon powder, and multi-walled carbon nanotubes) on 3-monochloropropane-1,2-diol (3-MCPD) esters were probed using refined palm oil as the research object. And acid-base modification was carried out on the optimum adsorbent to investigate the effects of adsorbent addition amount, adsorption time, and adsorption temperature on the adsorptive removal efficiency of 3-MCPD esters in palm oil. The results showed that the removal efficiency of 3-MCPD esters was as follows: wood-activated carbon powder >multi-walled carbon nanotubes>coconut shell-activated carbon powder >coal-activated carbon powder, but the overall removal effects were poor. The adsorption performance of the wood-activated carbon powder modified with 4 mol/L H3PO4 was improved. Under the optimal adsorption conditions of 5.85% addition, 47 min, and 103 ℃, the removal efficiency of 3-MCPD esters from palm oil could reach 71.82% . Wood-activated carbon modified by H3PO4 could be an effective strategy for the removal of 3-MCPD esters from edible oil.
The adsorptive removal effects of four adsorbents (wood-activated carbon powder, coconut shell-activated carbon powder, coal-activated carbon powder, and multi-walled carbon nanotubes) on 3-monochloropropane-1,2-diol (3-MCPD) esters were probed using refined palm oil as the research object. And acid-base modification was carried out on the optimum adsorbent to investigate the effects of adsorbent addition amount, adsorption time, and adsorption temperature on the adsorptive removal efficiency of 3-MCPD esters in palm oil. The results showed that the removal efficiency of 3-MCPD esters was as follows: wood-activated carbon powder >multi-walled carbon nanotubes>coconut shell-activated carbon powder >coal-activated carbon powder, but the overall removal effects were poor. The adsorption performance of the wood-activated carbon powder modified with 4 mol/L H3PO4 was improved. Under the optimal adsorption conditions of 5.85% addition, 47 min, and 103 ℃, the removal efficiency of 3-MCPD esters from palm oil could reach 71.82% . Wood-activated carbon modified by H3PO4 could be an effective strategy for the removal of 3-MCPD esters from edible oil.
2024, 39(1)
:57-63,117.
doi: 10.12187/2024.01.007
Abstract:
TGO-DSG oleogel (TDOG oleogel) was prepared with Torreya grandis oil (TGO) as the oil phase and Diosgenin (DSG) as the gelator, and its microstructure, rheological properties, texture properties, and crystal structure were investigated. The gelation mechanism of TDOG oleogel and the effect of gelation on the in-vitro digestion characteristics were also discussed. The results presented that TDOG oleogel was composed of small and dense or large and loose flocs DSG crystals, which were constructed through the fiber cross-linked three-dimensional network; the storage modulus (G') of TDOG oleogel was larger than the loss modulus (G″), and TDOG oleogel presented shear thinning characteristics, and the phase transition temperature was about 86.8 ℃. When the digestion time was 120 min, the digestibility of TDOG oleogel was 40.7% , significantly lower than that of TGO (50.9% ), indicating that gelation could reduce the digestibility of TGO in TDOG. In addition, the content of saturated fatty acids in the 120 min digestible supernatant of TDOG oleogel was higher than unsaturated fatty acids, indicating that oil gelation would increase the difficulty of digestion of unsaturated fatty acids, and the higher the unsaturation, the greater the digestion difficulty was. Therefore, TDOG oleogels could be used as an alternative to solid fats for the development of healthy functional foods.
TGO-DSG oleogel (TDOG oleogel) was prepared with Torreya grandis oil (TGO) as the oil phase and Diosgenin (DSG) as the gelator, and its microstructure, rheological properties, texture properties, and crystal structure were investigated. The gelation mechanism of TDOG oleogel and the effect of gelation on the in-vitro digestion characteristics were also discussed. The results presented that TDOG oleogel was composed of small and dense or large and loose flocs DSG crystals, which were constructed through the fiber cross-linked three-dimensional network; the storage modulus (G') of TDOG oleogel was larger than the loss modulus (G″), and TDOG oleogel presented shear thinning characteristics, and the phase transition temperature was about 86.8 ℃. When the digestion time was 120 min, the digestibility of TDOG oleogel was 40.7% , significantly lower than that of TGO (50.9% ), indicating that gelation could reduce the digestibility of TGO in TDOG. In addition, the content of saturated fatty acids in the 120 min digestible supernatant of TDOG oleogel was higher than unsaturated fatty acids, indicating that oil gelation would increase the difficulty of digestion of unsaturated fatty acids, and the higher the unsaturation, the greater the digestion difficulty was. Therefore, TDOG oleogels could be used as an alternative to solid fats for the development of healthy functional foods.
2024, 39(1)
:64-72.
doi: 10.12187/2024.01.008
Abstract:
This paper summarizes the research status and main problems in the types of cigar microorganisms and their application in field production, air-drying, fermentation and other links of domestic cigar tobacco leaves. It is believed that the microbial community of cigars could be divided into rhizosphere microorganisms, foliar microorganisms, and endophytic bacteria. The rhizosphere and leaf microorganisms of cigars could promote the growth and development of cigar plants, reduce plant diseases, and improve the sensory quality of tobacco leaves. However, there was a lack of research on beneficial endophytic bacteria. Microbial fertilizers and pesticides played an important role in the field growth of cigar tobacco leaves, but microbial fertilizers and pesticides for cigar tobacco plants had not been widely promoted and applied. During the process of cigar tobacco air-drying, there were abundant microbial resources and complex metabolic functions, but there was relatively little research on the mechanism of microbial action. During the fermentation process of cigar tobacco leaves, the microbial community structure gradually diversified. The addition of medium microorganisms could improve the quality of tobacco leaves and prevent the occurrence of mold. However, most studies focus on the screening of medium microorganisms, and there was still a lack of in-depth research on the mechanism of microbial improvement and aroma enhancement. In the future, in-depth research could be carried out on the screening and utilization of endophytes in cigar tobacco leaves, microbial changes in the air-drying process, and in-depth data mining by using omics technology, in order to further improve the beneficial role of microorganisms in the production process of domestic cigar tobacco raw materials, improve the production and the quality of tobacco leaves, and further reduce the dependence on imported cigar tobacco raw materials.
This paper summarizes the research status and main problems in the types of cigar microorganisms and their application in field production, air-drying, fermentation and other links of domestic cigar tobacco leaves. It is believed that the microbial community of cigars could be divided into rhizosphere microorganisms, foliar microorganisms, and endophytic bacteria. The rhizosphere and leaf microorganisms of cigars could promote the growth and development of cigar plants, reduce plant diseases, and improve the sensory quality of tobacco leaves. However, there was a lack of research on beneficial endophytic bacteria. Microbial fertilizers and pesticides played an important role in the field growth of cigar tobacco leaves, but microbial fertilizers and pesticides for cigar tobacco plants had not been widely promoted and applied. During the process of cigar tobacco air-drying, there were abundant microbial resources and complex metabolic functions, but there was relatively little research on the mechanism of microbial action. During the fermentation process of cigar tobacco leaves, the microbial community structure gradually diversified. The addition of medium microorganisms could improve the quality of tobacco leaves and prevent the occurrence of mold. However, most studies focus on the screening of medium microorganisms, and there was still a lack of in-depth research on the mechanism of microbial improvement and aroma enhancement. In the future, in-depth research could be carried out on the screening and utilization of endophytes in cigar tobacco leaves, microbial changes in the air-drying process, and in-depth data mining by using omics technology, in order to further improve the beneficial role of microorganisms in the production process of domestic cigar tobacco raw materials, improve the production and the quality of tobacco leaves, and further reduce the dependence on imported cigar tobacco raw materials.
2024, 39(1)
:73-78,96.
doi: 10.12187/2024.01.009
Abstract:
To investigate the changes in fungal community structure with mold occurrence during the industrial fermentation of cigar tobacco leaves, Dexue No.1 cigar tobacco leaf was chosen as the test material, and counting methods in microbiology and Illumina MiSeq high-throughput sequencing technology were used to analyze the changes in mold content and fungal community structure of normal and moldy cigar tobacco leaf samples during the industrial fermentation. The results indicated that compared to norml tobacco leaves, on the 30th day of fermentation, the mold content in moldy cigar tobacco leaves was the highest (8.3×104 CFU/g), the richness and diversity of species were the lowest, and the number of OTUs was the least. At the level of the phylum, Ascomycota was an absolute advantageous phylum on day 30 of fermentation, with an average relative abundance of 99.82% . At the level of the genus, Aspergillus was the main genus in the entire fermentation process, and the average relative abundance on day 30 of fermentation was the largest (92.32% ). The 30 d mildewy cigar tobacco leaf and other samples had a significant difference in species composition compared to normal tobacco leaves. Among them, Aspergillus was both an advantageous genus and a differential genus, and the average relative abundance of various samples was the highest.
To investigate the changes in fungal community structure with mold occurrence during the industrial fermentation of cigar tobacco leaves, Dexue No.1 cigar tobacco leaf was chosen as the test material, and counting methods in microbiology and Illumina MiSeq high-throughput sequencing technology were used to analyze the changes in mold content and fungal community structure of normal and moldy cigar tobacco leaf samples during the industrial fermentation. The results indicated that compared to norml tobacco leaves, on the 30th day of fermentation, the mold content in moldy cigar tobacco leaves was the highest (8.3×104 CFU/g), the richness and diversity of species were the lowest, and the number of OTUs was the least. At the level of the phylum, Ascomycota was an absolute advantageous phylum on day 30 of fermentation, with an average relative abundance of 99.82% . At the level of the genus, Aspergillus was the main genus in the entire fermentation process, and the average relative abundance on day 30 of fermentation was the largest (92.32% ). The 30 d mildewy cigar tobacco leaf and other samples had a significant difference in species composition compared to normal tobacco leaves. Among them, Aspergillus was both an advantageous genus and a differential genus, and the average relative abundance of various samples was the highest.
2024, 39(1)
:79-86.
doi: 10.12187/2024.01.010
Abstract:
To understand the differences in key quality indicators of domestic and foreign typical wrapper tobacco leaves, we determined the conventional chemical components and neutral aroma compounds in 40 samples of wrapper tobacco leaves from four countries: China, Brazil, Dominican Republic, and Indonesia. Key differential indicators were screened and correlated using partial least squares discriminant analysis (PLS-DA) and Pearson Correlation Analysis. The results indicated that: the total sugar and reducing sugar mass fractions of domestic wrapper tobacco leaves were significantly higher than those of foreign wrapper tobacco leaves, the nicotine mass fraction was significantly higher than that of Brazilian and Indonesian tobacco leaves, the nitrogen alkali ratio was significantly lower than that of Brazilian and Indonesian tobacco leaves, the potassium mass fraction was significantly lower than that of tobacco leaves from Brazil and the Dominican Republic. The total amount of neutral aroma compounds and the content of new phytodienes in domestic wrapper tobacco leaves were higher than those in foreign wrapper tobacco leaves, the content of phenylalanine degradation products was similar to that of tobacco leaves from Brazil, the Dominican Republic, and Indonesia, the content of browning reaction products was significantly higher than that of foreign wrapper tobacco leaves. There were a total of 16 different indicators of differences in wrapper tobacco leaves both domestically and internationally. Eleven indicators, including the content of the β-damascus ketone, guaiacol showed relatively high values in domestic wrapper tobacco leaves. The five indicators, including benzaldehyde content, total nitrogen mass fraction, and nitrogen alkali ratio, showed relatively high values in foreign wrapper tobacco leaves. Among the 16 differential indicators, the total nitrogen mass fraction and nitrogen to base ratio were highly significantly positively correlated with the content of dihydrokiwifruit internal fat, 2-acetylpyrrole, and benzaldehyde, and extremely significant negative correlation between the content of damarone and β-damascus ketone, the mass fractions of total sugar, reducing sugar, and nicotine had an inverse relationship with the neutral aroma substances mentioned above.
To understand the differences in key quality indicators of domestic and foreign typical wrapper tobacco leaves, we determined the conventional chemical components and neutral aroma compounds in 40 samples of wrapper tobacco leaves from four countries: China, Brazil, Dominican Republic, and Indonesia. Key differential indicators were screened and correlated using partial least squares discriminant analysis (PLS-DA) and Pearson Correlation Analysis. The results indicated that: the total sugar and reducing sugar mass fractions of domestic wrapper tobacco leaves were significantly higher than those of foreign wrapper tobacco leaves, the nicotine mass fraction was significantly higher than that of Brazilian and Indonesian tobacco leaves, the nitrogen alkali ratio was significantly lower than that of Brazilian and Indonesian tobacco leaves, the potassium mass fraction was significantly lower than that of tobacco leaves from Brazil and the Dominican Republic. The total amount of neutral aroma compounds and the content of new phytodienes in domestic wrapper tobacco leaves were higher than those in foreign wrapper tobacco leaves, the content of phenylalanine degradation products was similar to that of tobacco leaves from Brazil, the Dominican Republic, and Indonesia, the content of browning reaction products was significantly higher than that of foreign wrapper tobacco leaves. There were a total of 16 different indicators of differences in wrapper tobacco leaves both domestically and internationally. Eleven indicators, including the content of the β-damascus ketone, guaiacol showed relatively high values in domestic wrapper tobacco leaves. The five indicators, including benzaldehyde content, total nitrogen mass fraction, and nitrogen alkali ratio, showed relatively high values in foreign wrapper tobacco leaves. Among the 16 differential indicators, the total nitrogen mass fraction and nitrogen to base ratio were highly significantly positively correlated with the content of dihydrokiwifruit internal fat, 2-acetylpyrrole, and benzaldehyde, and extremely significant negative correlation between the content of damarone and β-damascus ketone, the mass fractions of total sugar, reducing sugar, and nicotine had an inverse relationship with the neutral aroma substances mentioned above.
Differential analysis of aroma compounds and aroma profiles of segmented smoke of two types of cigar
2024, 39(1)
:87-96.
doi: 10.12187/2024.01.011
Abstract:
In order to investigate the differences of aroma components and aroma profiles in segmented smoke of cigars, gas chromatography-mass spectrometry (GC-MS) was used to detect the aroma compounds of Great Wall No.2 and Montecristo No.4 cigars, supplemented by sensory evaluation and odor contribution weight to investigate the aroma characteristics of cigars, and the key aroma components in cigars were screened based on partial least squares discriminant analysis (PLS-DA). The results showed that the cigar was shorter, the interception effect was weakened, and the quantity and release of aroma components in cigar smoke were increased during smoking. In the odor contribution weight of segmented smoke of cigars, the bean and woody aromas of Great Wall No.2 weakened and the coffee aroma increased as smoking proceeded, while the bean aroma of Montecristo No.4 weakened and the spicy aroma increased. These changes in odor contribution weight were consistent with the results of the sensory evaluation. 12 key differential aroma components such as γ-hexalactone, 2-furoic acid, acetophenone, phenylacetic acid, 2,6-dimethylpyrazine were obtained during the smoking process of Great Wall No.2, and 11 key differential aroma components such as cedrol, 2-methylbutyraldehyde, 2-methoxy-4-vinylphenol, guaiacol, γ-nonanolactone were obtained during the smoking process of Montecristo No.4. The results of this study reflected the change rules of smoke composition in the smoking process of cigar and explained the reasons for the flavor changes in the smoking process of cigar.
In order to investigate the differences of aroma components and aroma profiles in segmented smoke of cigars, gas chromatography-mass spectrometry (GC-MS) was used to detect the aroma compounds of Great Wall No.2 and Montecristo No.4 cigars, supplemented by sensory evaluation and odor contribution weight to investigate the aroma characteristics of cigars, and the key aroma components in cigars were screened based on partial least squares discriminant analysis (PLS-DA). The results showed that the cigar was shorter, the interception effect was weakened, and the quantity and release of aroma components in cigar smoke were increased during smoking. In the odor contribution weight of segmented smoke of cigars, the bean and woody aromas of Great Wall No.2 weakened and the coffee aroma increased as smoking proceeded, while the bean aroma of Montecristo No.4 weakened and the spicy aroma increased. These changes in odor contribution weight were consistent with the results of the sensory evaluation. 12 key differential aroma components such as γ-hexalactone, 2-furoic acid, acetophenone, phenylacetic acid, 2,6-dimethylpyrazine were obtained during the smoking process of Great Wall No.2, and 11 key differential aroma components such as cedrol, 2-methylbutyraldehyde, 2-methoxy-4-vinylphenol, guaiacol, γ-nonanolactone were obtained during the smoking process of Montecristo No.4. The results of this study reflected the change rules of smoke composition in the smoking process of cigar and explained the reasons for the flavor changes in the smoking process of cigar.
2024, 39(1)
:97-102.
doi: 10.12187/2024.01.012
Abstract:
Using 5 grades of conventional cigarette finished tobacco as the research object, multiple linear regression analysis method was used to study the influence of physical indicators of cut tobacco on its rebound characteristics, and a prediction model for tobacco rebound characteristics based on BP neural network was constructed. The results showed that the degree of influence of physical indicators of cut tobacco on the rebound characteristics of tobacco was ranked from large to small as follows: broken tobacco rate>medium tobacco rate>long tobacco rate>filling value>elasticity>moisture content. Among them, medium tobacco rate, long tobacco rate, elasticity, and moisture content were positively correlated with the rebound characteristics of tobacco, while broken tobacco rate and filling value were negatively correlated with the rebound characteristics of tobacco. In the constructed BP neural network prediction model, the comparison between the predicted value of the test set and the true value R2 was 0.965 7, the overall model accuracy reached 98.10% . The difference between the predicted and measured values of cut tobacco rebound characteristics was small, and the model had high prediction accuracy and reliability, which could be used for accurate estimation of cut tobacco rebound characteristics.
Using 5 grades of conventional cigarette finished tobacco as the research object, multiple linear regression analysis method was used to study the influence of physical indicators of cut tobacco on its rebound characteristics, and a prediction model for tobacco rebound characteristics based on BP neural network was constructed. The results showed that the degree of influence of physical indicators of cut tobacco on the rebound characteristics of tobacco was ranked from large to small as follows: broken tobacco rate>medium tobacco rate>long tobacco rate>filling value>elasticity>moisture content. Among them, medium tobacco rate, long tobacco rate, elasticity, and moisture content were positively correlated with the rebound characteristics of tobacco, while broken tobacco rate and filling value were negatively correlated with the rebound characteristics of tobacco. In the constructed BP neural network prediction model, the comparison between the predicted value of the test set and the true value R2 was 0.965 7, the overall model accuracy reached 98.10% . The difference between the predicted and measured values of cut tobacco rebound characteristics was small, and the model had high prediction accuracy and reliability, which could be used for accurate estimation of cut tobacco rebound characteristics.
2024, 39(1)
:103-108.
doi: 10.12187/2024.01.013
Abstract:
In order to fully consider the random variation of sieving process parameters,this paper constructs the reliability-based optimization model for reconstituted tobacco process parameters,which taking the percentage of fibers below 12 mesh as the optimization objective,water flow rate and pulp concentration as the design parameters,and the percentage of fibers over 50 mesh as the probabilistic constraint. Firstly, the current process parameters are used as inheritance points for Latin hypercube sampling and screening experiments. Based on this, an initial Kriging model is constructed to fit the implicit relationship between water flow velocity, smoke slurry solid content, and the proportion of fiber mass below 12 mesh and above 50 mesh. And local adaptive sampling (LAS) was carried out to update the Kriging model to ensure the approximate accuracy of key positions at optimization iteration.Finally,Monte Carlo simulation (MCS)-Sequential quadratic programming (SQP) was used to solve the optimization model of screening process parameters. The results indicated that the optimized water flow rate and pulp concentration were 6.31 L/min and 0.53% , respectively. Under this process parameter, the proportion of fiber below 12 mesh was 13.72% , which was 7.19% higher than before optimization. The proportion of fibers over 50 mesh was 17.65% , which was a decrease of 4.13% compared to before optimization. This method could meet the optimization requirements of screening process parameters for paper making reconstituted tobacco leaves.
In order to fully consider the random variation of sieving process parameters,this paper constructs the reliability-based optimization model for reconstituted tobacco process parameters,which taking the percentage of fibers below 12 mesh as the optimization objective,water flow rate and pulp concentration as the design parameters,and the percentage of fibers over 50 mesh as the probabilistic constraint. Firstly, the current process parameters are used as inheritance points for Latin hypercube sampling and screening experiments. Based on this, an initial Kriging model is constructed to fit the implicit relationship between water flow velocity, smoke slurry solid content, and the proportion of fiber mass below 12 mesh and above 50 mesh. And local adaptive sampling (LAS) was carried out to update the Kriging model to ensure the approximate accuracy of key positions at optimization iteration.Finally,Monte Carlo simulation (MCS)-Sequential quadratic programming (SQP) was used to solve the optimization model of screening process parameters. The results indicated that the optimized water flow rate and pulp concentration were 6.31 L/min and 0.53% , respectively. Under this process parameter, the proportion of fiber below 12 mesh was 13.72% , which was 7.19% higher than before optimization. The proportion of fibers over 50 mesh was 17.65% , which was a decrease of 4.13% compared to before optimization. This method could meet the optimization requirements of screening process parameters for paper making reconstituted tobacco leaves.
2024, 39(1)
:109-117.
doi: 10.12187/2024.01.014
Abstract:
Anaerobic digestion process was established in the Up-flow Anaerobic Sludge Blanket (UASB). The study focused on the effect of ammonia nitrogen mass concentration on the performance of anaerobic digestion process for treating light industrial wastewater under normal and low-temperature conditions (<25 ℃). The results showed that intermitting sludge addition and controlling the reflux ratio of 7.5 were beneficial for the start-up of the anaerobic digestion process. Ammonia nitrogen mass concentration ranging from 400~1400 mg/L had no adverse effect on anaerobic digestion performance, while that in 400~800 mg/L slightly promoted anaerobic digestion performance. However, the higher ammonia nitrogen mass concentration led to the death of some microorganisms and an increase of the extracellular polymeric substance and soluble microbial products. In addition, the increase of ammonia nitrogen mass concentration was not conducive to the growth of hydrogenotrophic Methanobacterium. The relative abundance of Methanobacterium decreased from 75.5% to 6.3% . However, it was beneficial to the proliferation of acetotrophic Methanosaeta and facultative Methanosarcina and their relative abundances increased from 19.8% and 1.7% to 63.8% and 29.1% , respectively. Under normal and low temperature conditions, anaerobic digestion process could treat high COD light industrial wastewater with ammonia nitrogen mass concentration of 0~1400 mg/L, but the dominant methanogenic archaea would undergo significant revolution.
Anaerobic digestion process was established in the Up-flow Anaerobic Sludge Blanket (UASB). The study focused on the effect of ammonia nitrogen mass concentration on the performance of anaerobic digestion process for treating light industrial wastewater under normal and low-temperature conditions (<25 ℃). The results showed that intermitting sludge addition and controlling the reflux ratio of 7.5 were beneficial for the start-up of the anaerobic digestion process. Ammonia nitrogen mass concentration ranging from 400~1400 mg/L had no adverse effect on anaerobic digestion performance, while that in 400~800 mg/L slightly promoted anaerobic digestion performance. However, the higher ammonia nitrogen mass concentration led to the death of some microorganisms and an increase of the extracellular polymeric substance and soluble microbial products. In addition, the increase of ammonia nitrogen mass concentration was not conducive to the growth of hydrogenotrophic Methanobacterium. The relative abundance of Methanobacterium decreased from 75.5% to 6.3% . However, it was beneficial to the proliferation of acetotrophic Methanosaeta and facultative Methanosarcina and their relative abundances increased from 19.8% and 1.7% to 63.8% and 29.1% , respectively. Under normal and low temperature conditions, anaerobic digestion process could treat high COD light industrial wastewater with ammonia nitrogen mass concentration of 0~1400 mg/L, but the dominant methanogenic archaea would undergo significant revolution.
2024, 39(1)
:118-126.
doi: 10.12187/2024.01.015
Abstract:
In order to study the nitrogen and phosphorus removal performance of salt-containing food industry wastewater, the different doses of salinity were introduced into the food industry wastewater treatment system and the mode of operation was selected as anaerobic/anoxic/aerobic (A/A/O). The variation of different indicators including chemical oxygen demand (COD), NH4+-N, NO2--N, NO3--N, PO43--P were analyzed, and the influence mechanism about different concentrations of salinity on the nitrogen and phosphorus removal performance for the food industry wastewater was revealed combining with sludge properties and functional microorganisms. The results showed that the introduced salinity not only improved the COD degradation with the value increasing from 84.08% to 90.33% , but also improved phosphorus release of phosphorus removing bacteria and nitrification. The efficiency of NH4+-N increased from 95.79% to 98.85% . However, it restrained the absorption phosphorus of phosphorus removing bacteria in aerobic phase. The denitrification performance was enhanced under low salinity (0.5 g/L) condition, but was decreased when the salinity increased to 3.0 g/L. The extracellular polymeric substance (EPS) increased with salinity and the EPS was 38.81 mg/g volatile suspended solid (VSS) under the 3.0 g/L salinity condition. The introduced salinity increased the relative abundance of microbial community and changed its structure, which enhanced denitrifying bacteria enrichment including Chloroflexi、Actinobacteriota and Planctomycetota. It was also found that salinity increased the abundance of Caldilineaceae、Ferruginibacter and Kouleothrix but restrained the abundance of CandidatusCompetibacter. All of them guaranteed the stable nitrogen and phosphorus removal of treatment system.
In order to study the nitrogen and phosphorus removal performance of salt-containing food industry wastewater, the different doses of salinity were introduced into the food industry wastewater treatment system and the mode of operation was selected as anaerobic/anoxic/aerobic (A/A/O). The variation of different indicators including chemical oxygen demand (COD), NH4+-N, NO2--N, NO3--N, PO43--P were analyzed, and the influence mechanism about different concentrations of salinity on the nitrogen and phosphorus removal performance for the food industry wastewater was revealed combining with sludge properties and functional microorganisms. The results showed that the introduced salinity not only improved the COD degradation with the value increasing from 84.08% to 90.33% , but also improved phosphorus release of phosphorus removing bacteria and nitrification. The efficiency of NH4+-N increased from 95.79% to 98.85% . However, it restrained the absorption phosphorus of phosphorus removing bacteria in aerobic phase. The denitrification performance was enhanced under low salinity (0.5 g/L) condition, but was decreased when the salinity increased to 3.0 g/L. The extracellular polymeric substance (EPS) increased with salinity and the EPS was 38.81 mg/g volatile suspended solid (VSS) under the 3.0 g/L salinity condition. The introduced salinity increased the relative abundance of microbial community and changed its structure, which enhanced denitrifying bacteria enrichment including Chloroflexi、Actinobacteriota and Planctomycetota. It was also found that salinity increased the abundance of Caldilineaceae、Ferruginibacter and Kouleothrix but restrained the abundance of CandidatusCompetibacter. All of them guaranteed the stable nitrogen and phosphorus removal of treatment system.
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
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Postal Code：450001
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