Preservation methods

Preservation Methods and Maximum Holding Times for Selected Water and Wastewater Parameters... 

Leafy vegetables and some fruits in particular are rich sources of chlorophylls. However, they are ranked among the most perishable post-harvest products and must be consumed within a few days after harvest or subjected to preservation methods to extend their freshness. Their typical green color is, if not the most important sensory attribute, an extremely important parameter of quality. Any discoloration can lead to rejection by consumers as the bright green color is intuitively linked with freshness. 

Another potential problem with cyanide analysis is the recommended preservation method. The APHA standard method recommends preservation by adjusting to a pH of 12 using sodium hydroxide. The Department s laboratory has been using this method which is effective for total cyanide but unsatisfactory for free cyanide since the pH adjustment can change the cyanide species present, and thus the final result. There is no adequate preservation method for free cyanide. 

In addition to the need for an adequate method for free cyanide and an adequate sample preservation method, a methodology should be developed for the differentiation of species, especially between free (HCN and CM ), metallic complexes, and organic complexes. 

SiMiONE F and Brown EM (1991) ATCC preservation methods freezing and ffeeze-drying. 2nd edn. ATCC, Rockville, MD. 

Baert, L., Debevere, J., and Uyttendaele, M. (2009a). The efficacy of preservation methods to inactivate foodborne viruses. Int. ]. Food Microbiol. 131, 83-94. 

Acidification to pH 3 was a more effective preservation method than addition offormaldehyde. The losses of alcohol ethoxylates were less than 5% for Ci0 and C12 and up to 17% for CEO14. When the groundwater... 

Rowell, R.M. (1977a). Nonconventional wood preservation methods. In Wood Technology Chemical Aspects, Goldstein, I.S. (Ed.). ACS Symposium Series, 43, pp. 47-56. 

D Lichtenberg, Y Barenholz. Liposomes preparation, characterization, and preservation. Methods Biochem Anal 33 337-462, 1988. 

Traegardh, C. Hallstrom, B. Energy Analysis of Selected Food Post-Harvest and Preservation Systems, Irradiators Compared to Conventional Food Preservation Methods. Res. Contract No. 2850/TC, report to the International Atomic Energy Agency, Vienna, 1981. 

Difficulties in the morphological identification of parasites from other monogenean groups are expected because recent preservation methods favour molecular analyses. Alcohol preservation of larger monogeneans such as diplozoids increases the difficulty in species identification because the attachment clamps used for species discrimination of such preserved individuals are deeply embedded in parasite tissue and the accuracy of species identification is reduced. 

Physical preservation methods for foods, such as sterilization and drying, are associated with the application of heat. In these cases, because of its high temperature coefficient, the Maillard reaction becomes the dominant deteriorative reaction (1 2, 3). 

Wood preservatives - Methods for measuring losses of active ingredients and other preservative ingredients from treated timber - Part 1 Laboratory method for obtaining samples for analysis to measure losses by evaporation to air... 

Sometimes, the laboratories and instruments are not available immediately after sampling, especially when the sampling is carried out at remote areas. Under such conditions, storage of the collected samples is required. Preservation of the chemical identities of the sample is the prime objective. Selection of the preservation method depends on the type of sample, storage time, size, and number of samples. The temperature conditions for preserving biological... 

Encapsulation, a technique for grouping together a digital object and anything else necessary to provide access to that object, has been proposed by a number of researchers as a useful strategy in conjunction with other digital preservation methods. 

We use a variety of preservation techniques in order to minimize the degradation of contaminant concentrations in soil and water samples. Preservation methods stem from the chemical nature of each contaminant and from the rate at which it will undergo irreversible changes in a sample. Preservation is achieved by the application of one or more of the following techniques ... 

Preservation methods for water samples are diverse and depend on the chemical nature of the contaminants. Several analytical methods require chemical preservation of water samples with acid, base or other chemicals as shown in Appendix 13. Typical chemical preservation techniques for water samples and the underlying chemical reasons are as follows ... 

Advantages and Disadvantages of Selected Preservation Methods Used for Water... 

Examples of Preservation Methods of Water and Wastewater Samples for the... 

Burke, P.M., S. Hill, N. Iricanin, C. Douglas, P. Essex, and D. Tharin. 2002. Evaluation of preservation methods for nutrient species collected by automatic samplers. Environ. Monit. Assess. 80 149-173. 

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