This work determined that the percentage of suberin in cork may be found by solid‐state 13C cross polarization/magic angle spinning (CP/MAS) NMR spectroscopy and by FTIR with photoacoustic detection (FTIR‐PAS) spectroscopy. A linear relationship is found between the suberin content measured through CP/MAS spectral areas and that measured gravimetrically. Furthermore, application of a partial least squares (PLS1) regression model to the NMR and gravimetric data sets clearly correlates the two sets, enabling suberin quantification with 90% precision. Suberin quantitation by FTIR‐PAS spectroscopy is also achieved by a PLS1 regression model, giving 90% accurate estimates of the percentage of suberin in cork. Therefore, 13C‐CP/MAS NMR and FTIR‐PAS proved to be useful and accurate noninvasive techniques to quantify suberin in cork, thus avoiding the traditional time consuming and destructive chemical methods. © 2000 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 57: 344–351, 2000

Version 5.00 of the JCAMP-DX specifications were published for NMR and Mass Spectrometry file formats in Appl. Spectrosc.47, 1093-1099, (1993) and Appl. Spectrosc.48, 1545-1552, (1994). Since publication of these protocols developments in spectroscopy have led to a large number of requests for additions for applications not originally covered. Following careful consideration, it has become apparent that a few minor modifications will significantly increase the range of possible applications.In addition, new data labels have been introduced to ensure that files are year 2000 compliant and allow for conformity with good laboratory practices (GLP). These modifications are detailed in this publication as well as examples of the official NTUPLE JCAMP-DX definition as applied to NMR data.

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Fluorescence spectroscopy is a reliable and fast method for determining the deterioration of extra virgin olive oil (EVOO). EVOO was analysed by HPLC for determining antioxidant changes in EVOO due to heating at 170°C for 3 h. This thermal oxidation caused a significant exponential decrease in hydroxytyrosol (OH-Tyr) and vitamin E (vitE), while the reduction in the tyrosol content was relatively small. Hydroperoxydes were analysed by an indirect colorimetric method. Their content decreased exponentially during the heating process. Fluorescence excitation spectra with emission wavelength at 330 nm were recorded to monitor the evolution of polyphenols and vitE, while fluorescence excitation spectra with emission at 450 nm were used to monitor the evolution of hydroperoxydes. Results of partial least-square calibration models (PLS) show that the degradation of polyphenols, vitE and hydroperoxide, as well as formation of fluorescent components derivatives can be quantified with fluorescence spectroscopy. Application of chemometrical data analysis allows to optimise the extraction of the information contained in the data. Fluorescence can therefore be used as a rapid technique for evaluating the quality of heat-treated EVOO.