Hermetically sealed containers

The estabhshment of safe thermal processes for preserving food in hermetically sealed containers depends on the slowest heating volume of the container. Heat-treated foods are called commercially sterile. Small numbers of viable, very heat-resistant thermophylic spores may be present even after heat treatment. Thermophylic spores do not germinate at normal storage temperatures. 

The concept of heat processing of foods in hermetically sealed containers was introduced in 1810 (23). The role of microorganisms was unknown at the time, and only the so-called agents of putrefaction were eliminated. 

One other long-term condition that takes place with relatively low level DC fields in the presence of moisture is the migration of the metal of the conductor into the plastic. This was discovered to be a common thing in the past with silver conductors and phenolic insulators. The first instance of field failures were discovered in telephone equipment. The problem can occur with other metals with phenolic and also conceivably with other plastics that are moisture sensitive and can have a solvating action on the conductor metals that they contact. Most of these type plastics should be avoided inside hermetically sealed containers with movable contacts. Vapors released from the organic plastic deposit on the contacts to produce an insulation layer leading to contact failure. 

Since chemical reactions are accelerated by temperature increases, the recommendation is to store materials at the highest possible temperature consistent with practical limits—i.e.y 165°F., for the longest possible storage period. Storage data generated for liquid and slurry propellants are of two types (1) laboratory controlled experiments, and (2) field tests in hermetically sealed containers. The laboratory experiments provide for rapid and convenient determinations and are used primarily for comparing one propellant with another or for comparing the relative... 

For nitrocellulose supplied in hermetically-sealed containers (35-10% of water) the water content was determined by drying for 12 hr at a temperature of 45°C. Both... 

Basically, UHT milk is heat treated to 138 to 150°C (280 to 302°F) for one or two seconds by a process that renders the milk commercially sterile. The product is then placed in containers by an aseptic filling process and packaged in hermetically sealed containers. This combination of heat treatment and packaging results in milk that can be stored unrefrigerated for extended periods of time (Miller 1985 Arnold and Roberts 1982). 

The establishment of safe thermal processes for preserving food in hermetically sealed containers depends on the slowest heating volume of the containers. Heat-treated foods are called commercially sterile. 

Emulsion stability using a storage stability test Measure droplet size distribution and concentration at the top and bottom of a hermetically sealed container during storage Results usually expressed as plots of mean droplet size and concentration (volume fraction) as a function or storage time... 

Crystalline vitamin D3 is stored in hermetically sealed containers under nitrogen in a cool place and protected from light. Under such conditions, degradation is negligible for one year. Vitamin D3 exists in thermal equilibrium with previtamin D3 and the rate of equilibration markedly increases with temperature and time (1,2). 

A key issue in a glove box operation is order. The box must be equipped with shelves and should contain an appropriate set of tools. It is usually useful to have in the glove box a pair of long tweezers, paper tissues, hermetically sealed containers for disposal of used materials and a balance. 

Packaging and Storage Store in hermetically sealed containers under nitrogen in a cool place protected from light. 

Thermally Processed Low-Acid Foods Packaged in Hermetically Sealed Containers... 

White crystals. It is affected by air and light and should be stored in a cool place in hermetically sealed containers in which the air has been replaced by an inert gas. Solutions in volatile solvents are unstable. M.p. about 84°. 

Although great advances have been made in the techniques and mechanics of ampul production, Limousin s simple rules capture the basic underlying principles. In the United States, ampuls, or hermetically sealed containers which are filled with a medicinal liquid in a sterile condition, intended for parenteral use, became official in the National Formulary V (1926) that same year, the United States Pharmacopeia X included a chapter on sterilization but no monograph for individual ampuls. Iodine Ampuls, N.F., containing Iodine Tincture, United States Pharmacopeia, in sealed containers, intended to be broken and the liquid applied topically for the emergency disinfection of cuts or wounds, remained official through the National Formulary XIII (1970). The French term... 

Several studies have shown that anthocyanin stability increases with decreased water content, i.e., decreasing water activity (aw) (Wrolstad, 2000). Dry anthocyanin powders (aw < 0.3) are stable for several years when stored in hermetically sealed containers (Jackman and Smith, 1996). This property is advantageous when anthocyanins are produced into dry products and powders. Zajac et al. (1992) reported anthocyanin losses of 14% after 15 months of storage of a dry powder from black currant extracts at 20°C. When starch syrup or maltodextrins were included as carriers during the drying of the extracts, the anthocyanin losses were reduced to 2% and 3%, respectively. 

At the same time, scientists had been experimenting with metal containers to store food. The first metal canning of food took place in New York in 1812, when a small plant successfully canned oysters, meats, fruits and vegetables in hermetically sealed containers. 

Rubber closures for vials or other containers being filled aseptically on an industrial scale are nonporous but share some of the problems of porous loads. They are most frequently steam sterilized by passage through double-ended rotary washer autoclaves, which by agitation of the product ensure effective steam penetration to even the potentially occluded parts of the closures. Steam comes into direct contact with these bulk items they are not usually wrapped nor packed into hermetically sealed containers. Special precautions must be taken for unloading to avoid compromising their sterility. Static autoclaves may also be used for prew ashed versions of these types of components. They should then be loaded into the autoclave in shallow layers in perforated trays or boxes. 

The sample is retained in its trade package or in a container of the same material and construction. In the case of large containers, a smaller representative sample may be substituted. This allowance does not apply to hermetically sealed containers. 

Separate packaging and labelling operations of hermetically sealed containers are not subjected to section C.02.029 but are covered under section C.02.011. 

In the case of steam sterilization, the products to be sterilized with the exception of those in hermetically sealed containers must be packed in material which allows the evacuation of air and entry of steam but also prevents contamination after sterilization. 

If a mixture of steam and air is used for the sterilization of hermetically sealed containers with aqueous liquids, provision must be made that steam and air are uniformly mixed in the chamber and that the temperature is sufficiently high at all sites in the lot during the process in order to realize stariiization. In that case, the pressure in the chamber during the process must also be recorded. The findings form a part of the Lot Production Record. 

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