Fluorescence front-face

It is generally assumed the fluorescence and Fourier transform mid-infrared (FT-IR) spectroscopies do not suffer from the above-mentioned inconveniences and may be applied to turbid samples. Front-face (fluorescence) and attenuated total reflection (FT-IR) techniques may provide information on the structure of adsorbed proteins. 

FIG. 1 Schematic representations for (a) right-angle and (b) front-face fluorescence spectroscopies. 

Front-Face Fluorescence Spectroscopy and Mathematical Processing... 

The aim of this review was to summarize those aspects of fluorescence spectroscopy that may have value for solving problems in food science and technology. The techniques described, which are mainly based on front-face fluorescence spectroscopy coupled with multidimensional statistical methods, have been illustrated by examples taken from the literature and the work done in our laboratory. Although fluorescence spectroscopy is a technique whose theory and methodology have been extensively exploited for studies of both chemistry and biochemistry, the utility of fluorescence spectroscopy for molecular studies has not yet been fully recognized in food science. Fluorescence spectroscopy has the same potential to address molecular problems in food science as in the biochemical science field, because the scientific questions that need to be answered are closely related. We hope that this coverage will introduce a novel class of techniques in the emulsion and gel fields. 

Kulmyrzaev, A.A., Levieux, D., and Dufour, E. 2005. Front-face fluorescence spectroscopy allows the characterization of mild heat treatments applied to milk. Relations with the denaturation of milk proteins. J Agric Food Chem 53(3) 502-507. 

The experiment described in Figure 9.10 can be reproduced if front-face fluorescence is used. Otherwise, another experimental method should be applied to determine melting point of triglycerides. The following method can be used. Add 15-20 pi of skimmed milk into 1 ml of 1 N NaOH. The milk we used is enriched with vitamins E and B. By mixing slowly, you should soon obtain a clear and slightly pink solution. 

Dufour, E. (2002). Examination of the molecular structure of food products using front-face fluorescence spectroscopy. American Laboratory, 34, 51-55. 

Simple and rapid spectroscopic methods, such as front-face fluorescence, attenuated total reflectance Fourier-transform infrared and nuclear magnetic resonance spectroscopies, have a great potential for investigation of the structure of fats in dairy products and of the relation between structure and texture. Although fluorescence, infrared and NMR spectroscopies are techniques, the theory and methodology of which have been exploited extensively in studies in both chemistry and biochemistry, the usefulness of these spectroscopies for molecular studies has not been yet fully recognized in food science. Fluorescence, infrared and NMR spectroscopies coupled... 

Dufour, E., Riaublanc, A. 1997a. Potentiality of spectroscopic methods for the characterisation of dairy products. I. Front-face fluorescence study of raw, heated and homogenised milks. Lait 77, 657-670. 

Fig. 17. Front face fluorescence from a toluene solution containing pyrochlorophyll a dimer and pyropheophorbide a ethylene glycol monoester—. The addition of ethanol disrupts the structure shown in Fig. 16 and results in an increase in emission—.

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