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Handling major hypersensitivity reactions (e.g. celiac disease) triggered by proteins of wheat and other cereals is a challenging task for healthcare systems, legislative forces and the related fields of food analysis as well. In spite of the fact that there are available official threshold levels for labelling the absence of gluten, which is considered to be the toxic protein fraction of wheat, barley and rye, validation of the analytical methodology supporting regulatory requirements is currently problematic. The main limiting factors of method validation are the lack of reference methods and reference materials. The objective of this study was to provide a solution to this problem. An incurred reference material in a model food matrix was developed and studied by commercially available ELISA test kits as a part of the activity of the Food Allergen Working Group within the FP6 funded EU project MoniQA. After successful completion of the reference material development process, the incurred material was used as a basis of a comparative study examining the performance and applicability of seven commercially available ELISA kits designed for quantification of gluten/gliadin. In certain cases the obtained data showed discrepancies from the expected gliadin content that may carry both a food safety and an economic relevance. The evaluation of the effects of heat treatment on the analytical results is also presented, highlighting the fact that the food processing steps may have a considerable impact on the analytical data, thus should be carefully handled during method development and validation.

The evaporation of benzene, cyclohexane, n-heptane, toluene, 2-xylene, 3-xylene and 4-xylene was studied in H2, He, N2 or CO2 as purge gases for control of the introduced methods of evaluation and the sensitivity limits of TG measurements. Ii as a function of (1−α) and the following equation proved very suitable for a quantitative comparison of 28 independent and different TG measurements and for a very sensitive characterization of the thermal processes, even within an energy level difference of 3 kJ mol−1, in spite of the known great inconsistency in the formal kinetic parameters: $$\ln A \cong \overline {\left( {1/RT_{i} } \right)} {\kern 1pt} {\kern 1pt} \bar E_{i} {\kern 1pt} - \overline {n\ln \left( {1 - {\alpha }} \right)_{_{i} } } + {\kern 1pt} {\kern 1pt} \overline {\ln \left( {\ln {d\alpha /d}t} \right)_{_{i}}} $$

It follows from an analysis of the error levels of TG evaluation methods that it is a conceptual error to disregard the analogies of mass, energy and momentum streams of subordinate partial processes. This error is bypassed by means of the introduced method of dimensionless analysis and by determining the characteristic, constants-like data of thermal processes by using the measured data directly. These methods are very suitable for increasing the consistency of the calculated results by seeking for similarity, even in comparisons of measurements made under very different conditions and for emphasizing the differences too, quantitatively. With this new interpretation of TG processes, the idea of the kinetic compensation effect becomes only a consequence of the discussed conceptual error.

The self-hardening activity of fly ashes was investigated looking for the possibility of their chemical reactions with water without additives. A method had to be developed for separation of the structural water from the adsorbed or free one. The decomposition of the chemically bound water was measured by thermogravimetry. The 'r dimensionless number proved to be applicable for the quantitative eharacterisation of the measured data with more DTG peaks. The examined reaction depends on the chemical composition and the physical structure of the fly ashes and the time of interaction with water. The SO3 content seems important, but the characteristics of the formed compounds differ deeply from the CaSO4.2H20. The observed and examined reaction is an important factor of the self-hardening process of fly ash deposits.

Celiac disease and wheat allergy are the most common adverse reactions triggered by cereal proteins, mainly gluten, which is one of the 14 allergenic food ingredients that must be labeled on food products in the European Union (EU). To meet the requirements of this regulation, reliable analytical methodology for proper quantification of gluten is necessary. However, validation of presently used methods (ELISA and lateral flow device) is limited partly due to the lack of reference methods and incurred reference materials. To solve this problem, the goal of our work was to develop an incurred reference material for the quantification of gluten under the auspices of EU-FP6 funded Network of Excellence MoniQA. During this work, we produced a processed model product (cookie) containing gliadin (major allergenic fraction of gluten) in a defined amount. This paper addresses the development process of this material together with the associated problems (insufficient homogeneity and low recovery) and their solutions. As a result, an incurred food matrix was produced on a laboratory-scale with a potential use as a reference material. The model product was tested by an ELISA method followed by a comparative study of commercially available ELISA kits to investigate the applicability of the product. Preliminary results of this study are also presented.

Dimensionless number has been developed and introduced for quantitative analysis of the effect of thermogravimetric measuring factors like sample quantity, heating rate, etc. The TG, DTG and T data of different thermogravimetric measurements can be used directly for calculation of the three constants of analogy. TG data of CaCO3 measured in very different conditions show the method of transformation and its applicability for calculation of the correlation of measurements.

Li2SO4"H20 is an important model substance that is frequently used in research to solve problems of TG measurements and their kinetic evaluation. The article by Huang and Gallagher [ 1] is one of the best examples of the many levels of the problems and the problem-solving efforts via well-organized measurements and their accurate kinetic evaluations on powdered, pressed pellet, plate and cubic crystal samples. Sample masses ranged from 36 to 38 mg. The purge gases were dry or wet N2 for TG measurements, and dry N2 for DSC ones. The apparent kinetic constants were calculated on the basis of the Ozawa method at different heating rates: 10, 2 or 0.5 and 10, 5 or 2~ min -1 for TG and DSC measurements, respectively. The data in Tables 1-5 illustrate the kinetic compensation effect (CE), though they contain the effect of the different heating rates, i.e. the changes in the internal rates of the partial processes, too. For the data relating to dry and wet powder, pellet, plate and cubic samples, the regression coefficients of the straight lines are greater than 0.999, while for the DSC measurements they are greater than 0.996. This means that, by using the constants of CE (logA=aE-b) for all four dry samples and all the data in Tables 1-4 as one series (a=0.3303; 0.33426 and b=-3.3185; -3.31623), the E and logA values (e.g. a=0.14 (powdered) and a=0.85 (cubic crystal)) can be recalculated and compared with the results published in Tables 1 and 4 as follows

Although huge effort has been spent in the last decade on replacing chlorinated hydrocarbons with non-halogenated chemicals, they still play an important role in industrial production as well as in everyday life. Therefore, the application of low-cost process air cleaning technologies for existing production lines is necessary to meet recent air-emission requirements.

The "trial and error" method was used for a kinetic evaluation of the first DTG peaks of the alanine complexes of four lanthanide isothiocyanates (La, Ce, Pr and Nd) after well-organised preparation, sample control and TG measurements [ 1 ]. According to the authors, from 19 alternative possibilities, the reaction follows Eq. 18, with second-order kinetics. They also conclude that the decomposition processes of the four complexes are identical, as the corresponding parameters of the kinetic compensation effects (CE) are approximately the same. The correlation coefficient of the CE, however, is greater than 0.99 in each case (Table 10 [ 1 ]), so it is arbitrary to choose the second-order "mechanism" from the 19 examined alternative possibilities as the rate-determining one [2]. Similar arbitrary conclusions are frequently observed in the literature. In strict connection with the dimensionless evaluation, the following equation is suitable for characterisation of the thermal processes [3]

The kinetic region of the thermal decomposition of siderite is determined as a function of the single particle size. The kinetic constants are calculated from this region. Data are reported on the thermal decomposition of the FeCO 3 -SiO 2 and FeCO 3 -Al 2 O 3 mixtures.