Sterilization (microbiology) in the context of "Aseptic processing"

Asepsis is the state of being free from disease-causing micro-organisms (such as pathogenic bacteria, viruses, pathogenic fungi, and parasites). There are two categories of asepsis: medical and surgical. The modern day notion of asepsis is derived from the older antiseptic techniques, a shift initiated by different individuals in the 19th century who introduced practices such as the sterilizing of surgical tools and the wearing of surgical gloves during operations. The goal of asepsis is to eliminate infection, not to achieve sterility. Ideally, an operating field is sterile, meaning it is free of all biological contaminants (e.g. fungi, bacteria, viruses), not just those that can cause disease, putrefaction, or fermentation. Even in an aseptic state, a condition of sterile inflammation may develop. The term often refers to those practices used to promote or induce asepsis in an operative field of surgery or medicine to prevent infection.

A disinfectant is a chemical substance or compound used to inactivate or destroy microorganisms on inert surfaces. Disinfection does not necessarily kill all microorganisms, especially resistant bacterial spores; it is less effective than sterilization, which is an extreme physical or chemical process that kills all types of life. Disinfectants are generally distinguished from other antimicrobial agents such as antibiotics, which destroy microorganisms within the body, and antiseptics, which destroy microorganisms on living tissue. Disinfectants are also different from biocides. Biocides are intended to destroy all forms of life, not just microorganisms, whereas disinfectants work by destroying the cell wall of microbes or interfering with their metabolism. It is also a form of decontamination, and can be defined as the process whereby physical or chemical methods are used to reduce the amount of pathogenic microorganisms on a surface.

Disinfectants can also be used to destroy microorganisms on the skin and mucous membrane, as in the medical dictionary historically the word simply meant that it destroys microbes.

Carbon dioxide cleaning (CO₂ cleaning) comprises a family of methods for parts cleaning and sterilization, using carbon dioxide in its various phases. Due to being non-destructive, non-abrasive, and residue-free, it is often preferred for use on delicate surfaces. CO₂ cleaning has found application in the aerospace, automotive, electronics, medical, and other industries. Carbon dioxide snow cleaning has been used to remove particles and organic residues from metals, polymers, ceramics, glasses, and other materials, and from surfaces including hard drives and optical surfaces.

Pickling is the process of preserving or extending the shelf life of food by either anaerobic fermentation in brine or immersion in vinegar. The pickling procedure typically affects the food's texture and flavor. The resulting food is called a pickle, or, if named, the name is prefaced with the word "pickled". Foods that are pickled include vegetables, fruits, mushrooms, meats, fish, dairy and eggs.

Pickling solutions are typically highly acidic, with a pH of 4.6 or lower, and high in salt, preventing enzymes from working and micro-organisms from multiplying. Pickling can preserve perishable foods for months, or in some cases years. Antimicrobial herbs and spices, such as mustard seed, garlic, cinnamon or cloves, are often added. If the food contains sufficient moisture, a pickling brine may be produced simply by adding dry salt. For example, sauerkraut and Korean kimchi are produced by salting the vegetables to draw out excess water. Natural fermentation at room temperature, by lactic acid bacteria, produces the required acidity. Other pickles are made by placing vegetables in vinegar. Unlike the canning process, pickling (which includes fermentation) does not require that the food be completely sterile. The acidity or salinity of the solution, the temperature of fermentation, and the exclusion of oxygen determine which microorganisms dominate, and determine the flavor of the end product.

An X-ray machine is a device that uses X-rays for a variety of applications including medicine, X-ray fluorescence, electronic assembly inspection, and measurement of material thickness in manufacturing operations. In medical applications, X-ray machines are used by radiographers to acquire x-ray images of the internal structures (e.g., bones) of living organisms, and also in sterilization.

Strain 121 (Geogemma barossii (name not recognized by the International List of Prokaryotic Names by Standing in Nomenclature (LPSN)) is a single-celled microbe of the domain Archaea. First discovered within a hydrothermal vent in the Northeast Pacific Ocean near the Endeavor segment of the Juan de Fuca Ridge, Strain 121 is a hyperthermophile capable of reproducing at 121 °C (250 °F), hence its name. Strain 121 is biostatic at 130 °C (266 °F), so while the archaeon is unable to reproduce until it has been transferred to a cooler medium, it remains viable at temperatures up to 131 °C (268 °F). Strain 121 possess a coccoid shape with lophotrichous flagellation, reaching approximately 1 μm in diameter. Strain 121 metabolizes by reducing iron oxide (Fe(III)), a molecule that is abundant within the sediment in hydrothermal vents.

The maximum growth temperature of strain 121 is 8 °C higher than the previous record holder, Pyrolobus fumarii (T_max = 113 °C). At the time of its discovery, Strain 121 was the only known form of life that could tolerate such high temperatures, but in 2008 Methanopyrus kandleri was discovered to be able to reproduce at temperatures as high as 122 °C. Autoclaves, which are an important tool in sterilization, operate at temperatures of 121 °C (250 °F), marking Strain 121 a particularly notable discovery. Prior to the 2003 discovery of Strain 121, a fifteen-minute exposure to autoclave temperatures was believed to kill all living organisms. However, as Strain 121 is unable to reproduce at temperatures below 85 °C (185 °F), it cannot infect humans, who have an average body temperature of approximately 37 °C (99 °F).

A surgical drape is a sterile sheet used to create a sterile field during surgical procedures with the purpose of preventing the spread of infection from non-sterile to sterile areas and protecting the patient from contamination. The use of surgical drapes is a standard procedure in modern surgery . Surgical drapes come in various shapes and sizes, including those that are made of materials resistant to penetration by liquids and microorganisms.