Physical Methods Used to Control Microbial Growth
There are different methods to deal with microorganisms’ growth.
Write an essay about the various physical methods used by microbiologists to control microbial growth.
Guidelines:
Use APA guidelines for proper citations.
Essay’s minimum words: 500
Physical Methods Used to Control Microbial Growth
Microbiologists use different physical methods to control microbial growth for food preservation. The physical methods include high temperature, drying or desiccation, radiation, and filtration (Pleissner et al., 2020). Microbiologists use physical methods to disrupt microbial organisms by destroying the membranes, damaging proteins, changing permeability, and chemical modification.
Heating is one of the oldest forms of microbial such as cooking and canning. High temperature denatures proteins and changing membranes. Boiling is one of the oldest methods of exposing organisms to high temperatures for 10 minutes to 20 hours (Pleissner et al., 2020). Some microbial organisms can survive beyond the 20 hour boiling. For this reason, high temperature is not the best sterilization method to kill or control the growth of microbial growth.
Radiation is another method of killing microbial organisms. The methods of ionizing radiation include X-rays, gamma rays, and high-energy electron beams (Dukare et al., 2019). The radiation kills the cell components causing DNA mutation when a cell attempts to repair the damage. The accumulation of the cells leads to the death of the cells (Dukare et al., 2019). Radiation rays penetrate paper and plastic can be used to sterilize packaged products such as food products and laboratory equipment.
Sonication involves the use of high-frequency ultrasound waves to damage cell structures. The process causes a change in pressure in the ultra-cellular liquid leading to cavitation (Soares & Rousk, 2019). The formation of a bubble in the cell structure causes the cell to collapse. The process is effective in the laboratory since it allows the cell to release the contents (Soares & Rousk, 2019). Research centers can use the process to limit growth or carry out further research.
Desiccation is a process used to control microbial growth by preserving foods such as raisins. The process of dehydrating the cells is not effective in controlling microbial growth (Subramaniam et al., 2021). One of the reasons is because the process of dehydration cannot kill all microbes while others may start to regrow when the conditions become favorable. In some cases, food can be dried in the sun to eliminate moisture that can create a favorable environment for the growth of microbes (Subramaniam et al., 2021). The process of drying or dehydrating cells to undermine their growth can be done using salts and sugars. Microbiologists can add salt or sugar to prevent the further growth of microbes. For instance, salt is added to food such as meat to prevent the growth of microbes (Subramaniam et al., 2021). The method is not effective since the microbes can continue growing when the water activity is favorable.
Filtration is an effective method of controlling the physical growth of microbes. The process of filtration involves pore sizes that are small enough to filter bacteria and viruses (Pleissner et al., 2020). High-efficiency particulate air (HEPA) filters are used in clinical settings, cars, and airplanes. At home, HEPA filters can be used in vacuum cleaners, air purifiers, and air condition systems. For example, biological safety cabinets is an example of HEPA filters (Pleissner et al., 2020). Microbiologists can use biological safety cabinets to treat or clean the air by filtering out bacteria or viruses.
Microbiologists have a responsibility to select the best method of controlling microbial growth. The selection will depend on the risk of the growth if the favorable conditions resume (Dukare et al., 2019). It is important to assess the microbial organisms to determine the best method that will damage their cells and interfere with their growth.
References
Dukare, A. S., Paul, S., Nambi, V. E., Gupta, R. K., Singh, R., Sharma, K., & Vishwakarma, R. K. (2019). Exploitation of microbial antagonists for the control of postharvest diseases of fruits: a review. Critical reviews in food science and nutrition, 59(9), 1498-1513.
Pleissner, D., Lindner, A. V., & Ambati, R. R. (2020). Techniques to control microbial contaminants in nonsterile microalgae cultivation. Applied Biochemistry and Biotechnology, 192(4), 1376-1385.
Soares, M., & Rousk, J. (2019). Microbial growth and carbon use efficiency in soil: links to fungal-bacterial dominance, SOC-quality and stoichiometry. Soil Biology and Biochemistry, 131, 195-205.
Subramaniam, S., Jiao, S., Zhang, Z., & Jing, P. (2021). Impact of post‐harvest processing or thermal dehydration on physiochemical, nutritional and sensory quality of shiitake mushrooms. Comprehensive Reviews in Food Science and Food Safety, 20(3), 2560-2595.
