Foods artifacts

Deal, M. (1990), Exploratory analysis of food residues from prehistoric pottery and other artifacts from eastern Canada, SAS Bull. 13(1), 6-12. 

A. Devaraj, M. Izzetoglu, K. Izzetoglu, S. C. Bunce, C. Y. Li, and B. Onaral. Motion artifact removal in FNIR spectroscopy for real-world applications. In Nondestructive Sensing for Food Safety, Quality, and Natural Resources. Edited by Chen, Yud-Ren Tu, Shu-I. Proceedings of the SPIE, Volume 5588, pp. 22f-229 (2004)., pages 224-229, October 2004. 

Analytical chemistry applied to foods widely uses separation techniques in order to characterize foods on the basis of their major and minor constituent compounds. The minor compounds often highlight important differences rather than the major compounds. Chromatographic techniques have been widely applied however, when only gas chromatography (GC) was available, the application of this technique was severely limited by the thermal stability of the analytes. Derivatization reactions are able to somewhat protect organic molecules from degradation, but generally these procednres are rather time consuming and, sometimes, artifacts could be formed. 

UV absorption occurs only below 220nm, thereby it is affected by the interference from mobile phase and from artifacts in complex foods. A multiwavelength UV detection has been experimented successfully for unambiguous evaluation of pantothenic acid [609]. However, UV detection presents a low sensitivity, compared to other techniques, like FLD or MS. FLD is applied by using a postcolumn derivatization. Pantothenic acid is converted to 3-alanine by hot alkaline hydrolysis and a reaction with OPA [610]. Also MS is successfully applied to increase the sensitivity of pantothenic acid analysis. 

Adsorbent choice. The choice of adsorbent material depends on the volatile compounds in the food. Of the synthetic porous polymers, the most widely used and best overall adsorbent is Tenax TA (poly-2,6-diphenyl-p-phenylene oxide) 60 to 80 mesh. While Tenax does not show an adsorption capacity for all volatiles, especially very small polar compounds such as acetaldehyde, it has good thermal stability and desorption capabilities. It also traps little water and generates very few artifacts. Table G1.2.2 shows a few limitations and advantages of various adsorbents, all of which can be purchased from chromatography suppliers. If very small volatiles are the goal, various Carbosieves could be used, or traps containing several adsorbents in series. Traps with mixed adsorbents should be desorbed immediately, before transfer between phases occurs. 

Solid-phase extraction is routinely used to clean up extracts prior to quantitation (19,42,70, 80-82). Alternatively, endogenous fluorescent artifacts in food samples can be eliminated by oxidation with potassium permanganate/hydrogen peroxide/sodium metabisulphite. Benzyl alcohol has been used to extract riboflavin selectively without the coenzymes, permitting the determination of free riboflavin. 

There have been reports of significant concentrations of isomeric artifacts in the commercial coenzyme standards (83-87). Because the coenzymes are the predominant vitamers in most foods, failure to account for these impurities during quantitation of the coenzymes could result in significant analytical errors. Several methods have been suggested to compensate for the lack of purity in the commercial coenzyme preparations (83-85,88,89). 

Excavation in and around food preparation and serving locales can be extremely informative for determining the kinds of material culture employed in domestic settings. However, activity patterning is more difficult to document in public spaces, such as plazas, because these kinds of areas were often kept clean of refuse for practical purposes, including sanitation. Without de facto artifacts or in situ assemblages, it is nearly impossible to determine where food-related tasks occurred in relation to other activities. 

As reported earlier, several types of microscopy techniques can be used for the observation of food microstructure. They allow the generation of data in the form of images (Kalab et al., 1995). Because of the artifacts due to the preparation of samples before microscopy analysis, it is advisable to apply a variety of techniques to the same samples in order to compare the... 

Kalab, M. 1984. Artifacts in conventional scanning electron microscopy of some milk products. Food Microstruct. 3(2), 95-111. 

A substantial amount of information on volatiles can be obtained with less than 30 g of each of these samples in a direct DHS/GC/MS analysis. DHS operation sweeps volatile flavors from the surface of food samples in a similar way as we sniff for the volatile flavors of a food. DHS does not require high sampling temperature or solvent for extraction and may be considered as a lcw-artifact arcma sampling technique. The concentrating effect of DHS provides better sensitivity than static headspace sampling. Techniques such as GC-coupled aroma perception and GC/MS identification can be used to complement other approaches in improvement of flavor quality of a variety of products. 

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