Quality control tests

A number of analytical methods are used for assessing the quality and deterioration of oils or fat during refining and subsequent storage conditions. These methods are summarized below  

Lipolysis. Free fatty acids (FFA) result from lipolysis (hydrolysis) of oils and fats. This is determined by the FFA or acid value. The crude oils and animal fats usually have a FFA content exceeding 1 percent. The FFA content is lowered to less than 0.1 percent by the refining of oil or fat. 

Peroxide value. The oxidation of oils and fats leads to the formation of hydroperoxides. The hydroperoxides readily decompose to produce aldehydes, ketones, and other volatile products, which are characteristic of oxidation rancidity. The method for determination of peroxide concentration is based on the reduction of the hydroperoxide group with HI (or KI) to liberate free iodine, which may be titrated. The 

Shelf stability test Shelf life is predicted by the active oxygen method (AOM). The fat or oil is subjected to an accelerated oxidation test under standardized conditions so that the signs of deterioration are revealed within several hours or days. The sample is heated at 97.8°C while air is blown through it. The AOM value is reported as the number of hours to reach a peroxide value of 100 meq/kg. 

Riegel s Handbook of Industrial Chemistry, 9th ed., Chapman Hall, New York, 1992. 

Many of the tests used to characterise polyaryletheretherketone (PEEK) are simple industry standard techniques to measure properties such as mechanical, rheological, colour, fire, smoke or toxicity performance. However, some techniques require a specific knowledge of the polyaryletherketone (PAEK) literature. These include the characterisation of crystallisation, crystallinity, crystalline morphology, melting, molecular weight and chemical structure. Manufacturers also tend to have a number of proprietary quality control tests. 

In all materials used in different aspects of cellulose applications in food packaging, the material characteristics including cellulose, plasticizers, etc., and the fabrication procedures like composites, nanocomposites, casting of a film-forming solution, thermoforming, and so on, must be adapted to each specific food product and the conditions in which it will be used such as relative humidity, temperature, etc. Furthermore, edible and biodegradable films must meet a number of specific functional requirements like moisture barrier, gas barrier, water solubility, color and appearance, nontoxicity, etc. 

Therefore, for quality control of composites or film-forming mechanisms, many tests like mechanical and rheological characteristics, thermal properties, biodegradability, etc., are necessary [48,49]. 

Edible films and coatings must have organoleptic properties that are as neutral as possible (clear, transparent, odorless, tasteless, etc.) so as not to be detected when eaten. Enhancing the surface appearances (e.g., brilliance) and the tactile characteristics (e.g., reduced stickiness) can be required. It is possible to obtain materials with ideal organoleptic properties, but they must also be compatible with the food s filHng. Films and coatings can also help to maintain desirable concentrations of coloring, flavor, spiciness, acidity, sweetness, saltiness, etc. The optical properties of films depend on the film formulation and fabrication procedures [3]. 

Cellulose nanocomposites also have proper thermal, barrier and mechanical properties compared to today s biomaterials and can be synthesized from biopolymer and nanosized reinforcements [4]. 

Nowadays, our society faces many challenges due to environmental problems, which are the reason for the transition toward sustainability. The amount of nonde-gradable substances throughout the world is a fact, therefore, utilization of agricultmal 

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A specification or standard for product characteristics is valid only if it is matched with references to well defined and recognized test methods, such that quality control tests conducted by the parties involved —client and supplier, for example— are comparable even if they are performed at different locations. 

Example 1 Sample Quantity for Composition Quality Control Testing An example is sampling for quality control of a 1,000 metric ton (VFg) trainload of-Ks in (9.4 mm) nominal top-size bentonite. The specification requires silica to be determined with an accuracy of plus or minus three percent for two standard errors (s.e.). With one s.e. of 1.5 percent, V is 0.000225 (one s.e. weight fraction of 0.015 squared). The problem to be solved is thus calculating weight of sample to determine sihca with the specified error variance. 

In well-established processes, like ethylene oxidation to ethylene oxide, quality control tests for a routinely manufactured catalyst can be very simple if the test is developed on the basis of detailed kinetic studies and modeling of the performance in a commercial reactor. Tests must answer questions that influence the economics of the commercial process. The three most important questions are ... 

Quality control tests on the resins most commonly employed are for specific gravity, viscosity, colour, clarity and gel time under standard conditions,... 

Quality control tests are intended to detect produced materials which deviate from manufacturing specifications, and thus may result in questionable performance. The materials are usually subjected to spectrographic analysis which is the primary quality control check. The exposure tests are necessarily of short duration (hours or days), in which the test conditions attempt to reflect the environment of operation, for example using artificial seawater for a marine application. Since a property that is reproducible and indicative of a consistent quality anode is all that is required, there is no attempt to mirror, except in the crudest fashion, current density profiles. 

In conclusion it must be emphasised again that all the tests used are accelerated tests and only provide information on susceptibility to intergranular attack under the precise test conditions prevailing. They are quality control tests that may be used to demonstrate either that heat treatment has been carried out adequately or that a steel will withstand the test for a certain sensitising heat treatment. 

Design drawings Detail or fabrication drawings Materials requirements including composition, quality standards, and minimum structural properties Fabrication requirements and standards, including dimensional tolerances, allowable defects, and minimum structural properties Requirements for prototype and quality control tests and procedures Shipping and handling... 

The results of all quality control tests are always recorded in detail as, in those eountries in which the manufacture of vaccines is regulated by law, they are part of the evidence on which control authorities judge the suitability or otherwise of each batch of each preparation. 

Quality control tests or improvement of existing processes. Raw materials from various sources can be used in the manufacture of fine chemicals and pharmaceuticals. The raw materials can contain different impurities at various concentrations. Therefore, before the raw material is purchased and used in a full-scale batch its quality should be tested in a small-scale reactor. Existing full-scale procedures are subject to continuous modifications for troubleshooting and for improving process performance. Laboratory reactors used for tests of these two kinds are usually down-scaled reactors or reactors being a part of the full scale-reactor. 

N-terminal sequencing of the first 20-30 amino acid residues of the protein product has become a popular quality control test for finished biopharmaceutical products. The technique is useful, as it ... 

Quality control testing, of silicones, 22 601 Quality control unit, 27 159 Quality cost, 27 178 Quality factor, of filtration, 77 330 Quality Function Deployment (QFD), 27 172-173... 

Another use, now almost abandoned except for in natural product-derived chugs, is in quality control testing or batch release testing. The latter was once a mandated part of the standardization process for antibiotics, digoxin and insulin in the U.S. 

The knowledge and application of pharmaceutical and clinical calculations are essential for the practice of pharmacy and related health professions. Many calculations have been simplified by the shift from apothecary to metric system of measurements. However, a significant proportion of calculation errors occur because of simple mistakes in arithmetic. Further, the dosage forms prepared by pharmaceutical companies undergo several inspections and quality control tests. Such a luxury is almost impossible to find in a pharmacy or hospital setting. Therefore it is imperative that the health care professionals be extremely careful in performing pharmaceutical and clinical calculations. In the present chapter, a brief introduction is provided for the three systems of measurement and their interconversions ... 

Pressurised pipes for water and gas provide an example of design lives being predicted with confidence on the basis of a large assembly of data, of benchmark quality control tests for existing products, and of two-parameter accelerated testing for new ones. Some types of pipe are particularly sensitive to pressure extremes. Lifetime prediction cannot however take into account poor installation conditions. 

Thus prototype evaluation was performed using a variety of standardized tests, including various objective and subjective measures. Many of these laboratory tests were already being used to assess attributes of other products, either as quality control tests for ordinary soap bars or else in the development of detergent-based household products like laundry detergents or hard-surface cleansers. 

Shah VP. Dissolution a quality control test vs. a bioequivalence test. Dissol Technol 2001 ll(4) l-2. 

Shah VP. Dissolution quality control test vs. bioequivalence test. Dissolut Technol 2001 8(4) 6—7. 

In the last 10 years, the use of biorelevant testing conditions has become standard in the characterization of new compounds and the development of formulations. With some care, they can also be used as the basis for developing appropriate quality control tests, under consideration of appropriate pH and buffer capacity, by substituting appropriate synthetic... 

NMR can also be used to elucidate the structural features of a repeating unit in a polysaccharide and to investigate the conformation and dynamics of polysaccharides.21 A unique polysaccharide structure results in a characteristic proton NMR spectrum. Therefore, NMR is a powerful tool for identifying polysaccharide structures. This remarkable specificity has led to the development of a routine NMR-based identity assay, recently reported by Abeygunawardana et al. for quality control testing of bacterial polysaccharide to be used in formulating a polyvalent pneumococcal polysaccharide vaccine.22... 

Schenerman, M. A., and Bowen, S. H. (2001). Optimization, validation, and use of capillary gel electrophoresis for quality control testing of Synagis , a monoclonal antibody. Chromatographia 53(Suppl.), S66-S74. 

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