Preservatives prevention

Vof-beugung, /. prevention (Med) prophy laxis. -beugungsmassnahme, /. preventive (or prophylactic) measure, -beugungsmittel, n. preservative preventive (Med) prophylactic. -bild, n. pattern, model, standard prototype, type. 

Food preservatives prevent spoilage of food due to microbial growth. The most commonly used preservatives include table salt, sugar, vegetable oils and sodium benzoate, CeHgCOONa. Sodium benzoate is used in limited quantities and is metabolised in the body. Salts of sorbic acid and propanoic acid are also used as preservatives. 

Electron density distribution in the molecules presides over spin preservation preventing the redistribution of spin to other electrons in the system in form of polarization. 

Hexahydro-1,3,5-triethyl-s-triazine. Industrial preservative, prevents bacterial action in cutting oils, synthetic rubber latex, starch based adhesives, latex paint and aqueous slurries. It is soluble in acetone, ethyl alcohol, ether and water, moderately soluble in hydrocarbon solvents. 

Antioxidant preservative prevents oxidative rancidity development In oll-contalning foods by terminating free radicals formed during autoxidation of unsaturated lipids. It possesses antimicrobial activity as a phenolic compound. 

Preservatives are used in almost all multidose contact lens products. Because the potential for misuse of products by lens wearers is significant, preservatives prevent the potential proliferation of microorganisms. A contaminated product could ultimately lead to an ocular infection and possible loss of eyesight. Preservatives are considered active components when incorporated in products for the purpose of disinfecting contact lenses. The preservative must possess the antimicrobial... 

Preservatives Prevent microorganisms growth Hydrogen peroxide u J ... 

Sap fermentation does not cause dry-rot or decay. Decay results from the growth of wood-destroying fungi, and good preservatives prevent this growth by poisoning the wood. Tar is not an excellent preservative unless deeply injected into the wood, and this deep injection is seldom accomplished. Surface treatments with tar have been repeatedly shown to be ineffective. ... 

Preservatives keep food fresh by slowing the growth of mold and bacteria (antimicrobial preservatives), preventing oxidation (antioxidants), or slowing enzymes from continuing the ripening process after a fruit or vegetable was picked or cut. 

Cassens, R. G. 1994. Meat Preservation, Preventing Losses And Assuring Safety (1st ed.). Trumbull, CT Food and Nutrition Press, Inc. 

Clays and bentonites are used as fillers in adhesives. Sodium bisulfite, hydrogen peroxide, sodium perborate serve as bleaches. Solvents are added to help wet water-repellent surfaces. Preservatives prevent microbial growth. De-foamers prevent foam during cooking. Colloid stabilizers such as soaps and sodium chloride are often added. 

Sample Preservation Without preservation, many solid samples are subject to changes in chemical composition due to the loss of volatile material, biodegradation, and chemical reactivity (particularly redox reactions). Samples stored at reduced temperatures are less prone to biodegradation and the loss of volatile material, but fracturing and phase separations may present problems. The loss of volatile material is minimized by ensuring that the sample completely fills its container without leaving a headspace where gases can collect. Samples collected from materials that have not been exposed to O2 are particularly susceptible to oxidation reactions. For example, the contact of air with anaerobic sediments must be prevented. 

Fluoridation of potable water suppHes for the prevention of dental caries is one of the principal uses for sodium fluoride (see Water, municipal WATER treatment). Use rate for this appHcation is on the order of 0.7 to 1.0 mg/L of water as fluoride or 1.5 to 2.2 mg/L as NaF (2). NaF is also appHed topically to teeth as a 2% solution (see Dentifrices). Other uses are as a flux for deoxidiziag (degassiag) rimmed steel (qv), and ia the resmelting of aluminum. NaF is also used ia the manufacture of vitreous enamels, ia pickling stainless steel, ia wood preservation compounds, caseia glues, ia the manufacture of coated papers, ia heat-treating salts, and as a component of laundry sours. 

The function of the essential oil in the plant is not fully understood. Microscopic examination of plant parts that contain the oil sacs readily shows their presence. The odors of flowers are said to act as attractants for insects involved in pollination and thus may aid in preservation and natural selection. Essential oils are almost always bacteriostats and often bacteriocides. Many components of essential oils are chemically active and thus could participate readily in metaboHc reactions. They are sources of plant metaboHc energy, although some chemists have referred to them as waste products of plant metaboHsm. Exudates, which contain essential oils, eg, balsams and resins, act as protective seals against disease or parasites, prevent loss of sap, and are formed readily when the tree tmnks are damaged. 

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