Food products analysis

LaPorte, M.F. andPaquin, P. (1998) Near-infrared technology and dairy food products analysis areview. Semin. Food Anal., 3, 173-190. 

Diagnosis of food products (analysis of the composition and impurities) Material engineering (especially in the field of ultrahigh-puiity materials, such as those used in crystallography and the semiconductor industry)... 

Mamfoiu, C. Tofana, M. Nica-Badea, D. Popescu, A. Thin layer chromatography. In Food Products Analysis Etnograph Cluj-Napoca, 2005. 

Supercritical fluid chromatography has found many applications in the analysis of polymers, fossil fuels, waxes, drugs, and food products. Its application in the analysis of triglycerides is shown in Figure 12.38. 

Discriminant Sensory Analysis. Discriminant sensory analysis, ie, difference testing, is used to determine if a difference can be detected in the flavor of two or more samples by a panel of subjects. These differences may be quantitative, ie, a magnitude can be assigned to the differences but the nature of the difference is not revealed. These procedures yield much less information about the flavor of a food than descriptive analyses, yet are extremely useful eg, a manufacturer might want to substitute one component of a food product with another safer or less expensive one without changing the flavor in any way. Several formulations can be attempted until one is found with flavor characteristics that caimot be discriminated from the original or standard sample. 

The development of precise and reproducible methods of sensory analysis is prerequisite to the determination of what causes flavor, or the study of flavor chemistry. Knowing what chemical compounds are responsible for flavor allows the development of analytical techniques using chemistry rather than human subjects to characterize flavor (38,39). Routine analysis in most food production for the quaUty control of flavor is rare (40). Once standards for each flavor quaUty have been synthesized or isolated, they can also be used to train people to do more rigorous descriptive analyses. 

Pimento Berry Oil. The pimento or allspice tree, Pimenta dioca L. (syn. P. officinalis, Liadl.), a native of the West Indies and Central America, yields two essential oils of commercial importance pimento berry oil and pimenta leaf oil. The leaf oil finds some use ia perfumery for its resemblance to clove leaf and cinnamon leaf oils as a result of its high content of eugenol. Pimento berry oil is an item of commerce with extensive appHcation by the flavor industry ia food products such as meat sauces, sausages, and pickles, and moderate use ia perfumery, where it is used primarily as a modifier ia the modem spicy types of men s fragrances. The oil is steam-distilled from dried, cmshed, fully grown but unripe fmits. It is a pale yellow Hquid with a warm-spicy, sweet odor with a fresh, clean topnote, a tenacious, sweet-balsamic-spicy body, and a tea-like undertone. A comparative analysis of the headspace volatiles of ripe pimento berries and a commercial oil has been performed and differences are shown ia Table 52 (95). 

Ultrasound Sample Prepai ation method was used for the analysis of food products. 

Whilst solving some ecological problems of metals micro quantity determination in food products and water physicochemical and physical methods of analysis are employed. Standard mixture models (CO) are necessary for their implementation. The most interesting COs are the ones suitable for graduation and accuracy control in several analysis methods. Therefore the formation of poly functional COs is one of the most contemporary problems of modern analytical chemistry. The organic metal complexes are the most prospective class of CO-based initial substances where P-diketonates are the most appealing. 

The analysis of complex matrices, such as natural products, food products, environmental pollutants and fossil fuels, is today a very important area of separation science. The latest developments in chromatographic techniques have yielded highly efficient systems, used with specific detectors to obtain high selectivity and or sensitivity. 

GC using chiral columns coated with derivatized cyclodextrin is the analytical technique most frequently employed for the determination of the enantiomeric ratio of volatile compounds. Food products, as well as flavours and fragrances, are usually very complex matrices, so direct GC analysis of the enantiomeric ratio of certain components is usually difficult. Often, the components of interest are present in trace amounts and problems of peak overlap may occur. The literature reports many examples of the use of multidimensional gas chromatography with a combination of a non-chiral pre-column and a chiral analytical column for this type of analysis. 

On-line LC-GC has frequently been used as a clean-up technique for the analysis of trace levels of contaminants (pesticides, plasticizers, dyestuffs and toxic organic chemicals) in water and food products. Several different approaches have been proposed for the analysis of contaminants by on-line LC-GC. Since pesticide residues occur at low concentration in water, soil or food, extraction and concentration is needed before GC analysis is carried out. 

Often, planar chromatography is used as a preparative step for the isolation of single components or classes of components for further chromatographic separation or spectroscopic elucidation. Many planar chromatographic methods have been developed for the analysis of food products, bioactive compounds from plant materials, and essential oils. 

The methods of analysis of polymer additives and chemicals, such as hydrocarbons, alcohols, etc., are not only restricted to the field of polymer chemistry but can also be applied for the analysis of such materials in the field of food chemistry. In addition, the analysis of polyaromatic hydrocarbons in edible oils has been of extreme importance. Polymeric packaging materials that are intended for food-contact use may contain certain additives that can migrate into the food products which are actually packaged in such products. The amounts of the additives that are permitted to migrate into food samples are controlled by government agencies in order to show... 

The researcher in food and its analysis is keenly aware that his task will not be finished until the quality of a food product can be defined completely in precise terms of its flavor, color, texture, and nutritive value. The goal is distant but the journey is well begun. The papers contained herein describe the present state of affairs in each of as many of the fields of food analysis as time for the symposium permitted. Each has been covered by an outstanding worker in his field. It is unfortunate that B. L. Oser s excellent paper on Advances in Vitamin Determination does not appear. His more comprehensive review of food analysis which appeared in Analytical Chemistry [21, 216 (1949)] should by all means be studied along with the papers contained herein. 

In the final analysis, market price and sales volume are functions of the quality standards offered and the buyer s degree of confidence that the product will conform to the standards. Maintenance of buyer s confidence requires inspection to screen out all nonconforming products, or control over variability of quality during production and distribution to a degree where few, if any, products fail to meet the standards. Screening inspection of the finished product cannot improve quality it merely serves to segregate unacceptable from acceptable product, and results in loss of production capacity and costly waste and salvage. The second consideration provides the only sound basis for quality control in frozen food production and distribution. It operates on the old principle that an ounce of prevention is worth a pound of cure. ... 

Typical examples that fall in this group would be the determination of the active ingredients in analgesic tablets for pharmaceutical use, such as aspirin or codeine or the analysis of a food product such as margarine. Examples of both these analyses will be described to illustrate the sample preparation procedure. 

From this analysis it is clear that in addition to their benefits, the use of pesticides in food production not only causes serious public health problems but also considerable damage to vital agricultural and natural ecosystems in the United States and world. A conservative estimate suggests that the environmental and social costs of pesticide use in the United States total about 4 billion each year. Worldwide the yearly environmental and public health costs are probably at least 100 billion. This is several times the 18 bllllon/yr spent on pesticides in the world. 

This analysis has demonstrated that pesticide use in the world could be reduced by approximately 50% without any reduction in crop yields (in some cases increased yields) or the food supply. This effort would require applying pesticides only-when-necessary plus using various combinations of the nonchemical control alternatives currently available (34). Although food production costs might Increase slightly (0.5% to 1%), the added costs would be more than offset by the positive benefits to public health and the environment (15). 

Schoefs, B., Chlorophyll and carotenoid analysis in food products. A practical case-by-case view. Trends Anal. Ghent., 22, 335, 2003. 

Lloyd, A.G., Extraction and chemistry of cochineal. Food Chem., 5, 91,1980. Yamada, S. et al.. Analysis of natural colouring matters in food (IV). Methylation of cochineal colour with diazomethane for analysis of food products, J. Agric. Food Chem., 41, 1071, 1993. 

The official permission to use a synthetic colorant in food is determined by its quality and safety. Detailed and accurate analysis became compulsory in order to verify purity and quantify the labeled concentrations of colorants in food. For the analysis of synthetic colorants added to food products, (1) simple and rapid methods are used to determine their presence, (2) accurate and precise methods evaluate then-concentrations, or (3) certain methods evaluate their degradations to unstable and unsafe forms. This chapter is dedicated to these three methods used to identify and quantify synthetic colorants as pure or mixed pigments in foodstuffs. 

Because of peak overlappings in the first- and second-derivative spectra, conventional spectrophotometry cannot be applied satisfactorily for quantitative analysis, and the interpretation cannot be resolved by the zero-crossing technique. A chemometric approach improves precision and predictability, e.g., by the application of classical least sqnares (CLS), principal component regression (PCR), partial least squares (PLS), and iterative target transformation factor analysis (ITTFA), appropriate interpretations were found from the direct and first- and second-derivative absorption spectra. When five colorant combinations of sixteen mixtures of colorants from commercial food products were evaluated, the results were compared by the application of different chemometric approaches. The ITTFA analysis offered better precision than CLS, PCR, and PLS, and calibrations based on first-derivative data provided some advantages for all four methods. ... 

Hong F, S Pehkonen (1998) Hydrolysis of phorate using simulated and environmental conditions rates, mechanisms, and product analysis. J Agric Food Chem 46 1192-1199. 

The experimental designs discussed in Chapters 24-26 for optimization can be used also for finding the product composition or processing condition that is optimal in terms of sensory properties. In particular, central composite designs and mixture designs are much used. The analysis of the sensory response is usually in the form of a fully quadratic function of the experimental factors. The sensory response itself may be the mean score of a panel of trained panellists. One may consider such a trained panel as a sensitive instrument to measure the perceived intensity useful in describing the sensory characteristics of a food product. 

Examples of recent applications of food RMs for quality control in the analysis of foods and food products... 

Several methods have been discussed for the determination of method limitations when evaluating procedures for the determination of pesticides in food. A brief comparison of the methods discussed for the determination of the detection and quantification limits of methods used for the analysis of food products can be found in Table 2. 

N. Haagsma and C. van der Water, Immunochemical methods in the analysis of veterinary drug residues, in Analysis of Antibiotic Drug Residues in Food Products of Animal Origin, ed. V. K. Agarwal, Plenum Press, New York, pp. 81-97 (1992). 

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