fermentation engineering refers to a new technology that uses modern engineering technology to produce useful products for human beings by using some specific functions of microorganisms, or directly applies microorganisms to industrial production processes. The contents of fermentation engineering include strain selection, medium preparation, sterilization, expanded culture and inoculation, fermentation process and product separation and purification.
(1) "fermentation" includes "fermentation strictly defined by microbial physiology" and "industrial fermentation", and the term "fermentation engineering" should be "industrial fermentation".
(2) In industrial production, products are processed or made by "industrial fermentation", and the corresponding processing or making process is called "fermentation process". In order to realize industrial production, it is necessary to solve the engineering problems of industrial production environment, equipment and process control to realize these processes (fermentation processes), so there is "fermentation engineering".
(3) Fermentation engineering is a discipline to solve the engineering problems of industrialized production according to fermentation technology. From the engineering point of view, fermentation engineering divides the fermentation industrial process to realize fermentation technology into three stages: strain, fermentation and refining (including wastewater treatment). These three stages have their own engineering problems, and they are generally called upstream, midstream and downstream projects of fermentation engineering respectively.
(4) Microorganism is the soul of fermentation engineering. In recent years, the understanding of the biological properties of fermentation engineering has become increasingly clear, and fermentation engineering is approaching science.
(5) The basic principle of fermentation engineering is the biological principle of fermentation engineering.
(6) Fermentation engineering has three development stages.
In the modern sense, fermentation engineering is an open subject with strong technology and application, which is formed by the intersection and integration of many disciplines. Fermentation engineering has experienced three stages of development: agricultural manual processing-modern fermentation engineering-modern fermentation engineering.
Fermentation engineering originated from family or workshop-style fermentation production (manual processing of agricultural products), and later it used chemical engineering for reference to realize industrial production (modern fermentation engineering). Finally, it went back to nature to study, design and guide industrial fermentation production (modern fermentation engineering) centering on microbial life activities, and entered the ranks of bioengineering.
The original manual workshop-style fermentation production relies on the skills and experience handed down by ancestors to produce fermented products, which is heavy in physical labor and limited in production scale, making it difficult to realize industrial production. Therefore, the predecessors in the fermentation field first asked for advice from chemistry and chemical engineering, learned from agricultural chemistry and chemical engineering, standardized the fermentation production process, replaced the manual handling with pumps and pipelines, and replaced the manual operation with machine production, which successfully pushed the workshop-style fermentation production to the level of industrial production. The combination of fermentation production with chemistry and chemical engineering contributed to the first leap in fermentation production.
Through decades of practice in industrial fermentation production, people gradually realize that the industrial fermentation process is a dynamic biological process with time-varying (time-varying), nonlinear and multivariable input and output. It is often difficult to get the expected results if we deal with the problems of industrial fermentation production (especially large-scale production) according to the mode of chemical engineering. From the point of view of chemical engineering, fermentation tank is also a reactor for the fermentation of raw materials, and the microbial cells cultured in fermentation tank are only a catalyst. According to the orthodox thinking of chemical engineering, it is of course difficult for microorganisms to exert their unique production potential. Therefore, we trace back to the biological core (microorganism) of workshop-style fermentation production technology, return to nature and have a new understanding of the attributes of fermentation engineering. The identification of biological properties of fermentation engineering has made the development of fermentation engineering have a clear direction, and fermentation engineering has entered the category of bioengineering.
Fermentation engineering refers to a technology that uses some functions of organisms (mainly microorganisms) and active in vitro enzymes to produce useful biological products for human beings, or directly uses microorganisms to control some industrial production processes. Well-known examples are beer, fruit wine and industrial alcohol produced by yeast fermentation, cheese and yogurt produced by lactic acid bacteria fermentation, and large-scale production of penicillin by fungi. With the progress of science and technology, fermentation technology has also developed greatly, and it has entered the stage of modern fermentation engineering that can artificially control and transform microorganisms to make these microorganisms produce products for human beings. As an important part of modern biotechnology, modern fermentation engineering has broad application prospects. For example, genetic engineering is used to purposefully transform the original strain and improve its yield; Using microbial fermentation to produce drugs, such as human islet, interferon and growth hormone.
has developed from the simple production of alcoholic beverages, acetic acid and fermented bread to an extremely important branch of bioengineering today, and has become a multidisciplinary project including microbiology, chemical engineering, genetic engineering, cell engineering, mechanical engineering and computer software and hardware engineering. Modern fermentation engineering not only produces alcoholic beverages, acetic acid and bread, but also produces many medical and health care drugs such as insulin, interferon, growth hormone, antibiotics and vaccines, produces agricultural means of production such as natural pesticides, bacterial fertilizers and microbial herbicides, and produces amino acids, spices, biopolymers, enzymes, vitamins and single cell proteins in the chemical industry.
in a broad sense, fermentation engineering consists of three parts: upstream engineering, midstream engineering and downstream engineering. The upstream project includes the selection of excellent seed plants, the determination of optimum fermentation conditions (pH, temperature, dissolved oxygen and nutrient composition), and the preparation of nutrients. Mid-stream project mainly refers to the technology of cultivating a large number of cells and producing metabolites in fermentor under the optimal fermentation conditions. There should be a strict aseptic growth environment here, including the technology of sterilizing fermentation raw materials, fermentation tanks and various connecting pipes by high temperature and high pressure before fermentation begins; Air filtration technology of continuously introducing dry sterile air into fermentation tank during fermentation; Computer control technology for controlling feeding speed according to cell growth requirements during fermentation; There are also different techniques for seed culture and production culture. In addition, according to different needs, batch fermentation is also classified in fermentation technology: one-time feeding fermentation; Fed-batch fermentation: that is, on the basis of one-time feeding fermentation, a certain amount of nutrients are fed to make cells grow further or get more metabolites; Continuous fermentation: continuously add nutrients and take out the fermentation broth. Before any large-scale industrial fermentation, a large number of experiments must be carried out in a laboratory-scale small fermentor to obtain the kinetic model of product formation, and according to this model, the fermentation requirements of the pilot test are designed, and finally the kinetic model of larger-scale production is designed from the pilot test data. Due to the complexity of biological reaction, there will be many problems in the process from laboratory to pilot plant, from pilot plant to large-scale production, which is the problem of fermentation engineering process amplification. Downstream engineering refers to the technology of separating and purifying products from fermentation broth, including solid-liquid separation technology (centrifugal separation, filtration separation, precipitation separation, etc.), cell wall-breaking technology (ultrasound, high-pressure shearing, osmotic pressure, surfactant and lywallzyme, etc.), protein purification technology (precipitation, chromatography separation and ultrafiltration, etc.), and finally product packaging and processing technology (vacuum drying and freeze drying, etc.). In addition, in the fermentation industry that produces drugs and food, it is necessary to strictly abide by the regulations of cGMPs published by the Federal Food and Drug Administration of the United States, and regularly accept the inspection and supervision on *.
a brief history of fermentation engineering
the fermentation engineering of alcohol, glycerol and acetone in the 192s belonged to anaerobic fermentation. Since then, the fermentation project has experienced several major turning points and is constantly developing and improving.
in the early 194s, with the discovery of penicillin, the antibiotic fermentation industry gradually rose. Because penicillin-producing bacteria are aerobic, microbiologists have successfully introduced aeration stirring and a set of aseptic techniques on the basis of anaerobic fermentation technology, and established deep aeration fermentation technology. It greatly promotes the development of fermentation industry, and enables organic acids, probiotics and hormones to be produced on a large scale by fermentation.
in 1957, glutamic acid was successfully produced by microorganisms in Japan, and now 2 kinds of amino acids can be produced by fermentation. The development of amino acid fermentation industry is based on the new technology of metabolic control fermentation. On the basis of in-depth study of microbial metabolic pathways, scientists obtained the mutant types suitable for producing a certain product by artificial mutagenesis of microorganisms, and then cultivated them under artificial control to produce a large number of substances needed by people. At present, metabolic control fermentation technology has been used in the production of nucleotides, organic acids and some antibiotics.
since 197s, with the development of bioengineering technologies such as genetic engineering and cell engineering, fermentation engineering has entered a new stage of directional breeding, and new products have emerged one after another.
Since 198s, with the continuous cross and infiltration between disciplines, microbiologists have begun to comprehensively study the fermentation process with mathematics, dynamics, chemical engineering principles and computer technology, which makes the control of the fermentation process more reasonable. In some countries, it has been able to automatically record and control all the parameters of the fermentation process, which has obviously improved the production efficiency.