The advantages of supercritical CO2 extraction and its application in the tobacco industry
The extraction temperature is 40 ° C, the extraction pressure is 25-30MPa, the amount of entrainer is 4% -6%, the flow rate of CO2 is 2L / min, and the extraction time is 3 Hours, the extraction rate of tobacco net oil can be increased to more than 8%.
Extraction temperature: 40 ° C
Amount of entrainer:4%-6%
Flow rate of CO2:2L/min
the extraction rate of tobacco net oil can be increased to more than 8%
The advantages of supercritical fluid extraction (SFE) and the applications of supercritical extraction in the tobacco industry are reviewed:
1. Extract tobacco-specific substances from tobacco residues;
2 Extract natural flavors and fragrances from natural flavors;
3 Extract the active ingredients of Chinese herbal medicine to develop low-hazard, health-care cigarettes;
4. Tobacco analysis and other applications;
5 Prospects for the application of supercritical extraction in the tobacco industry.
Supercritical fluid extraction (SFE) is a new chemical separation technology that has achieved rapid international development since the 1980s. It has been widely used in the process of producing more expensive pure natural products with natural products as raw materials. , Is listed as one of the most widely used modern technologies in the tobacco industry.
Characteristics of supercritical CO2 extraction
The application of supercritical CO2 extraction technology for the extraction of Chinese herbal medicine, tobacco-specific components and natural flavors and tobacco flavors overcomes the shortcomings of traditional separation methods such as solvent separation, steam distillation, pressing, and Soxhlet extraction, and preserves the original product. Some flavors and nutritional ingredients conform to the world trend of advocating natural food and returning to nature, and have their unique advantages:
① The critical temperature of CO2 is low, at 31.2 ℃, it can relatively well preserve natural effective ingredients without being damaged or secondary, especially suitable for the extraction of components with strong thermal sensitivity and easy oxidative decomposition.
② The solubility of supercritical CO2 fluid is related to the density of the fluid, and small changes in temperature and pressure will cause a large change in the density of the fluid, which will affect its solubility. Therefore, by adjusting the operating pressure and temperature conditions, the enrichment of impurities can be reduced, the effective ingredients in natural products are enriched at high concentrations, the appearance of the product is greatly improved, the extraction efficiency is high, and there is no solvent residue.
③ Supercritical CO2 extraction is not simply to purify a certain component, but to selectively separate the active ingredients, which is more conducive to the advantages of natural ingredients restricting each other and acting synergistically.
④ Supercritical CO2 can also directly extract different parts from a single formula or multi-component formula or directly extract extracts for screening, greatly improving the screening speed. At the same time, many substances that cannot be extracted by traditional methods can be extracted, and it is easier to find new ingredients from natural materials.
⑤The extractant CO2 is non-toxic, harmless, non-flammable and explosive, low viscosity, low surface tension, low boiling point, and no pollution.
⑥ It can be directly used in combination with G C, IR, MS, L C, etc. to objectively reflect the concentration of effective ingredients in the extract, and realize the integration of extraction and analysis testing.
⑦Supercritical extraction has fast extraction time and short production cycle. Once the supercritical CO2 extraction cycle begins, separation begins. Generally, components are separated and precipitated after 10 minutes of extraction, and can be completely extracted in about 2-4 hours. At the same time, it does not require concentration and other steps. Even if an entrainer is added, it can be removed by the separation function or simply concentrated.
⑧Supercritical CO2 extraction, easy to control operating parameters, simple process, stable active ingredients and product quality. At the same time, supercritical CO2 extraction not only saves energy, but also greatly reduces the use of organic solvents, and the pollution of the three wastes is small.
Application of supercritical CO2 extraction in tobacco
1. Extracting tobacco-specific ingredients and improving the comprehensive benefits of tobacco
China is a large tobacco country. Due to the influence of factors such as geographical environment, planting technology, and climate, a certain amount of low-grade tobacco cannot be purchased every year. These waste tobaccos can neither be incinerated nor used as fertilizer, which becomes a burden on tobacco farmers. In addition, nearly a third of the tobacco rods in the tobacco factory were discarded as waste. A small amount of inferior materials such as shredded tobacco and tobacco powder are also produced during the rolling and processing of cigarettes. Reprocessing into cigarettes will affect the inherent quality of the cigarette. If it is directly discarded, it will not only cause pollution, but also a waste of resources. However, these waste tobaccos contain a variety of valuable ingredients, such as nicotine, solanesol, sugars, organic acids, etc., of which nicotine, solanesol, etc. are very important valuable components in tobacco. By using the supercritical extraction method, extracting valuable components such as nicotine and tobacco net oil can play a role of turning waste into treasure and comprehensive utilization, improving the comprehensive benefits of tobacco, and at the same time protecting the environment.
1.1 Nicotine extraction
Nicotine, also known as nicotine, is a unique alkaloid in tobacco. Its chemical name is 1-methyl-2 (3'-pyridyl) pyrrolidine, its molecular formula is C10H14N2, and its relative molecular mass is 162. It is a heterocyclic compound containing helium. Although nicotine is highly toxic, it is widely used in chemical industry, pesticides and medicine. Nicotine acts on the central neurotransmitter system through its receptors, increasing the release of dopamine, and thus has a protective effect on the pathogenesis of Parkinson's disease. At the same time, nicotine is used as an intermediate raw material for the treatment of cardiovascular, skin, snake venom bite and other diseases. The demand is increasing, especially high-purity natural nicotine, which has become one of the most sought-after products on the international market. Using tobacco leaves as raw materials, the use of supercritical CO2 extraction, acid-base pretreatment, and column chromatography separation processes to separate and purify nicotine can obtain pure nicotine with a purity of more than 98%.
1.2 Extraction of tobacco net oil
Tobacco net oil is a kind of high-quality tobacco flavor similar to natural raw materials. Its volatile chemical components have been identified by GC / MS analysis. They mainly include 3-methylvaleric acid, valeric acid, noracetolide, and dihydrokiwi. Esters, daunone, β-damascenone, neophytadiene, β-ionol, sclarinone and other tobacco flavoring ingredients. Tobacco net oil has the effect of transmitting the aroma of tobacco, making the smoke sweet, delicate and soft, reducing irritation, covering up the odor, and obviously improving the smoking quality of cigarettes. The supercritical mixed fluid is used to extract tobacco net oil from the flavor tobacco extract. The extraction temperature is 40 ° C, the extraction pressure is 25-30MPa, the amount of entrainer is 4% -6%, the flow rate of CO2 is 2L / min, and the extraction time is 3 Hours, the extraction rate of tobacco net oil can be increased to more than 8%.
1.3 Extraction of Solanesol
Solanesol is a triple sesquiterpene alcohol (Solanesol), which is a waxy white solid with a melting point of 41.5-42.5 ° C and is easily soluble in organic solvents. Solanesol accounts for 0.3% -4.5% of the total weight of tobacco. Solanesol plays a very important role in biochemistry and is an important raw material for drug synthesis. It is an intermediate of pantocase, and can also be used as a side chain of medicinal co-mycoprotein Q (a medicine for treating heart disease) and vitamin K. Because solanesol itself contains multiple non-conjugated double bonds, it has a very strong ability to absorb free radicals. Using supercritical extraction, solanesol can be extracted from tobacco residues or tobacco net oil.
2. Extracting Chinese herbal medicine ingredients and developing new cigarette products
Chinese herbal medicine is China's traditional medicine. As a natural medicine, it has a long history and ranks first in the world. Chinese herbal medicine can not only be used for health care and treatment, but also widely used in China's tobacco industry. It is mainly used in the development of pharmaceutical health-care cigarettes, the use of its active ingredients to reduce the harmfulness of cigarettes, and its use in the prevention and treatment of tobacco viruses.
Cigarettes containing active ingredients of natural Chinese herbal medicines have health-care functions and are an important branch of Chinese cigarettes. The successful development of Chinese herbal medicine cigarettes has caused a sensation in the domestic and foreign cigarette markets, and has brought a wide range of applications for supercritical CO2 extraction technology in the extraction of Chinese herbal medicine ingredients.
At the same time, some active Chinese herbal medicine ingredients also have a certain effect on reducing cigarette tar and harmful components. The use of Schisandra chinensis, Agastache, licorice, and deodorant extracts as cigarette additives can reduce harmful gas phase free radicals in cigarette smoke. The herbal additive extracted from Astragalus membranaceus can reduce TPM (content) by about 3.73 mg / branch, and can reduce the mutagenicity of TPM. Using Shouwu and other Chinese herbal medicines as raw materials, the alcohol solution obtained through processing and extraction, sprayed into mixed type tobacco shreds at 5% added amount, can reduce the amount of cigarette tar by 4-6mg / branch, and the polycyclic aromatic hydrocarbons in tar, Both benzo a pyrene and free radicals were greatly reduced. This physicochemical method using Chinese herbal medicine to reduce the amount of cigarette tar has opened up a new way to improve the hygienic conditions of cigarettes and alleviate the contradiction between smoking and health. Another application of Chinese herbal medicine in tobacco is to use its extract to enhance the antiviral ability of tobacco and improve the quality of tobacco leaves. Studies show that Chinese herbal medicine Jiu, trans, wood and 0.1% ZnSO4 have positive effects on vegetative growth, photosynthetic performance and root vigor of tobacco, can also increase the activity of lipoxygenase, and make the incidence and disease index of tobacco mosaic virus disease decline. Among them, the effect of two treatments is better. 15 Chinese herbal medicines such as Coptis chinensis, Chenpi, Eucommia ulmoides are scientifically compatible, and have inhibitory effects on tobacco plant tissue metabolism and enzyme activity. It can be made into a tobacco leaf curing agent, which significantly improves the appearance and intrinsic quality of tobacco leaves, and enhances the grade structure.
3. Extraction of natural flavors and fragrances for tobacco
With the improvement of people's living standards, the sensory quality requirements for the aroma and harmony of cigarette products are becoming higher and higher, and the requirements for the variety and quality of flavor of cigarette products are becoming higher and higher. The world more and more trusts the concept of "natural is safety", so natural fragrances occupy an extremely important position in the flavor and fragrance industry. Because natural fragrances have unique aromas that cannot be replaced by synthetic fragrances, they contain many Trace ingredients with special contributions in aroma and natural flavors are mostly non-toxic and side-effect, so they are widely used in the design of cigarette products.
The volatile aromatic components of many plants, essential oils, can be used as tobacco flavors. Most of these components are unstable and susceptible to thermal deterioration or volatility. The use of supercritical CO2 extraction at low operating temperatures has become a traditional steam distillation and organic Ideal alternative for solvent extraction.
With China's entry into the WTO, reducing coke and harm has become an urgent task for the Chinese tobacco industry. The technology of reducing coke and harm is a complex technology. It is required that cigarettes must retain their high aroma while reducing coke. Protect the interests of consumers. When the comprehensive coke reduction technology is adopted, flavor and flavor must be added to maintain and enhance the aroma of the cigarette. In addition to adding tobacco net oil, the extraction and application of natural flavor and flavor is also an important approach. There are also many reports of such studies at home and abroad.
The volatile oil of grass and fruit extracted with supercritical CO2 liquid has an average oil yield of 3.36%. It has been identified by chromatograph-mass spectrometry and contains 61 kinds of flavor components. The cigarette flavoring test can obviously improve and modify the cigarette aroma and cover up. Miscellaneous gas, improving aftertaste, softening the smoke, delicate aroma, and obviously improving the quality of the smoke. Fenugreek seed extract is used in the flavoring and adding test of cigarettes. Through the component identification and evaluation, it can be concluded that the fenugreek product extracted by supercritical extraction has a higher quality than the tincture extracted by ordinary solvents.
The supercritical CO2 stream extraction method was used to extract the essential oil from Xinyi. The oil yield of Xinyi essential oil was 4.2%, which was about 73% higher than that of steam distillation. Guangxi Academy of Sciences has used supercritical CO2 extraction method to study the extract of lingering herbs. The average product content is over 95% and the yield is over 1.2%, which is 5-6 times higher than the ordinary steam distillation method. The stability of the obtained lingering products Good, unique aroma, strong fragrance, natural aroma, good color, good solubility, it is one of the high-end natural tobacco flavors and fragrance products.
4. Application in tobacco analysis
The use of SFE in chromatographic technology has developed Superceitical Fluid Chromatography (SFC). Supercritical fluid chromatography (SPC) is a chromatographic process in which supercritical fluid is used as the mobile phase. An effective and fast analysis method for easily pyrolysable substances. It combines the characteristics of fast, efficient, high selectivity, and high separation efficiency of chromatographic analysis. It opens a new way for the analysis of organic compounds and becomes suitable for the analysis of difficult to volatilize and easily heat An effective and fast way to dissolve polymer materials. It is widely used in tobacco analysis and drug analysis. Tobacco analysis is mainly used to analyze the unique N-nitrosoamine (TSNA) in tobacco. SFC is used to analyze tobacco compounds with high sensitivity. Capillary SFC is used to analyze tobacco. For nitro and nitroso compounds, the detection limit can reach p8.
The application of supercritical fluid chromatography with chloroform as the extractant and the use of SFC and Ion (Ion Mobility Detector) to analyze nicotine in cigarettes and tobacco leaves is a simple, sensitive and practical analysis of nicotine and other alkaloids. method. Compared with the current analytical method, the SFC-Ikm method not only has the advantage of high sensitivity, but also its equipment cost is relatively low. It is a very promising development to analyze nicotine and nicotine metabolites in tobacco. Analytical method. At the same time, carbon dioxide supercritical extraction can be used as an efficient sample preparation technology for tobacco chemical composition analysis and cigarette quality research. As a pretreatment method for tobacco chemical analysis, carbon dioxide supercritical extraction has the advantages of simplicity, fastness, good data reproducibility, high degree of extraction automation, and no pollution. Tobacco carbon dioxide supercritical extracts are mainly non-polar and weakly polar compounds, which are closely related to the quality of cigarettes.
1. Due to the high investment and maintenance costs of SEF-CO2 high-pressure equipment, high design and manufacturing technology requirements, and the inability to continuously operate the extraction kettle, the production capacity is low. Secondly, the foundation is extremely weak in basic research, and the basic data is seriously lacking. There are still some difficulties in general application in industry. First of all, coupled with reasons such as industrial secrecy, it is even more difficult to make breakthroughs in research. With the close cooperation of personnel from different industries, jointly solving some engineering and technical problems, and gradually improving the basic data, Ultrapro extraction will make greater progress in the tobacco industry.
2. Although SFC has high sensitivity in tobacco analysis, the number of compounds detected is still very small, and it is limited to a small number of compounds such as nitro and nitroso. Therefore, the research and development of SFC instruments, methods and conditions for compounds contained in tobacco has great potential.
3. At present, the residues from the extraction of nicotine from tobacco residues can be used as raw materials for the production of tobacco flakes for papermaking. There are few reports on the extraction of residues from raw materials such as natural flavors and Chinese herbal medicines to the tobacco industry, and further research is needed.