Food analysis application

Guillo, C. Lipp, M. Radovic, B. Reniero, F. Schmidt, M. Anklam, E. Use of Pyrolysis-Mass Spectrometry in Food Analysis Applications in the Food Analysis Laboratory of the European Commissions Joint Research Center. J. Anal. Appl. Pyrolysis 1999,49, 329-335. 

Several new methods and instruments based on infrared spectroscopy are being developed for food applications. Advances in spectroscopic instruments and data analysis have enabled the rapid and nondestructive analysis of cheese parameters in just a few seconds (e.g., Nicolet Antaris FT-NIR by Thermo Electron Corp.). Another recent development is the miniaturization of FTIR instrumentation, which would enable onsite analysis, while the cheese is being produced. The TruDefender FT handheld FTIR by Ahura Scientific, Inc. (Fig. 5.7) is a portable handheld spectrometer that could be applied to food analysis. With numerous developments in FTIR spectroscopy and several potential food analysis applications still unexplored, there is great research potential in this technique that could benefit the industry and research institutions. 

It is with the topic of analyte determination in foods by the technique of analytical AAS that this chapter is concerned. Analyte quantitation (d above) by this technique is thus the main thrust of this treatment, but of necessity, the intimately related procedures of sample treatment (b) and analyte separation and manipulation (c) will also be discussed insofar as they bear on quantitative measurement by AAS. Food for human consumption is the main concern of this chapter. Peripheral discussion, however, of allied commodities such as plants and animal feedstuffs, is included to make the treatment more comprehensive, especially in areas where there is a dearth of publications relating to food-analysis applications of atomic spectrometry. For detailed accounts of methodologies bearing on such related materials, the reader is referred to the other chapters in this volume. 

The FAAS procedure described above, is suitable for the majority of food-analysis applications. In some instances, however, low manganese contents will dictate the use of SEFAAS or EAAS techniques [202—205]. An interesting multielement (Cd, Cu, Co, Mn, Ni, Pb and Zn) scheme using chelating ion exchange has been outlined by Baetz and Kenner [206]. 

In view of the importance of the application of these techniques in CE analysis, the chapter presents an overview on the most recent applications of chemo-metrics to optimize CE and CE-MS parameters, focusing on pharmaceutical, environmental, and food analysis applications mainly in the last 5 years. The chapter has been divided into six main sections corresponding to an introduction, three main applications (pharmaceutical, environmental, and foods), an additional section summarizing other recent studies in differing fields, and a final section including concluding remarks and future perspectives. 

Comparison with a univariate approach. Also applicable in food analysis applications. 

S. Chang, et al. Food analysis—applications review, Anal. Chem. 65, 334R (1993). 

PLS is a powerful technique that shares the advantages of both the CLS and ILS methods hut does not suffer from the limitations of either these methods. A PLS calibration can, in principle, he based on the whole spectrum, although in practice the analysis is restricted to regions of the spectrum that exhibit variations with changes in the concentrations of the components of interest. As such, the use of PLS can provide significant improvements in precision relative to methods that use only a limited number of frequencies [9]. In addition, like the inverse least squares method, PLS treats concentration rather than spectral intensity as the independent variable. Thus, PLS is able to compensate for unidentified sources of spectral interference, although all such interferences that may be present in the samples to be analysed must also be present in the calibration standards. The utility of PLS will be demonstrated by several examples of food analysis applications presented in Section 4.7. 

Numerous books cover the topic of sampling methods in infrared spectroscopy (see, e.g., references [10-12]), and a detailed description of all the various alternatives is beyond the scope of this chapter. Instead, we will focus on the two sampling methods that are most commonly employed in food analysis applications, namely, the use of transmission cells for recording the spectra of solutions and the total internal reflection technique, also known as attenuated total reflectance (ATR). Readers who wish to learn about the techniques not covered here may consult the references cited above. 

Guillou C, Lipp M, Radovic B, et al. (1999) Use of pyrolysis-mass spectrometry in food analysis Applications in the food analysis laboratory of the European Commissions Joint Research Centre. Journal of Analytical and Applied Pyrolysis 49 329-335. 

Nowadays, it is clear that nanotechnology offers valuable tools for building new architectonics for analytical microsystems. Apart from their high sensitivity and inherent miniaturization, another added functionality of ED is the opened opportunity to modify these surfaces suitably with nanomaterials to break frontiers in new food analysis applications. In food microfluidic analysis, two relevant nanomaterial examples have been explored as novel electrochemical detectors coupled to ME carbon nanotubes (CNTs) [45, 46] and metallic nanowires (MNWs) [47]. 

Perez-Lopez, B., Merkoci, A., 2011. Nanomaterials based biosensors for food analysis applications. Trends Food Sci. TechnoL 22, 625—639. 

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