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The effect of the presence of drying oils in paper supports on the rate of cellulose degradation is investigated in a novel manner using Solid Phase Micro-extraction (SPME), which is employed to analyse volatile organic compounds (VOCs), emitted from oiled paper. This technique is applied as a non-destructive means of analysing original works of art on paper, in order to detect volatile cellulose degradation products. It is also applied to artificially aged paper samples with and without oil, in order to investigate the extent to which the presence of drying oil accelerates the degradation of cellulose. Furfural and other volatile cellulose degradation products containing a furan ring are selected as representative cellulose degradation products to be measured for the purpose of the investigation. It is demonstrated, by the finding of increased emissions of the selected compounds, that the presence of drying oils accelerates the thermal and oxidative degradation of cellulose in cotton paper and two types of wood pulp based papers.

Greek coffee is a traditional product of superior aroma and flavor. Changes of aroma volatile compounds of ground roasted coffee can occur during storage, leading to “coffee staling” which affects the quality and acceptability of the brew. Temperature and water activity effect quality especially during home storage, after opening of the vacuum pack (secondary shelf-life). The objective was to define volatile indices of greek coffee quality and model their change as a function of temperature and water activity during storage. Greek coffee samples were equilibrated at constant water activities a w (0.15, 0.22, 0.33, 0.52) and stored at constant temperatures (25, 35, 45 °C). The profile of volatile compounds was obtained directly from ground coffee samples using purge and trap-gas chromatography-mass spectrometry methodology. Furfural was considered to be a good aroma marker of greek coffee staling during storage; furfural changes (expressed by coffee aroma loss rate constants, k vol ) were well correlated to storage temperature T and a w . Increase of water activity (for a w values above 0.33) and increase of storage temperature (from 25 to 45 °C) caused decrease of shelf life estimated based on aroma indices for greek coffee. The shelf life for coffee samples of a w 0.52 stored at temperatures 25 and 45 °C was found to be 82-92 and 20-23 days, respectively. At 45 °C, a w decrease from 0.52 to 0.33 led to shelf life increase from 20-23 to 36-41 days. Additionally, coffee aroma loss was expressed based on sensory evaluation (scores for aroma intensity and overall impression, 1-9). Rate constants for coffee aroma loss based on sensory scoring of coffee brews were calculated (k sens ). A comprehensive mathematical model of 3 parameters that describes the effects of storage temperature and water activity on k vol and k sens was developed allowing the calculation of shelf life (SL) for greek coffee during (home) storage.

Introduction The efficiency of analytical methods for the determination of food additives is of utmost importance since their content in food affects both quality and safety of foods. Objective The objective of the present article is to survey the current status of analytical methods for certain food additives (namely, colours, sweeteners, preservatives and antioxidants) and to point out the needs for the improvement of the existing, or the development of new, analytical methods. Method The criteria used to select the specific additives from among other categories of food additives, comprise broad use, legislative limits, and high frequency of notification through the Rapid Alert System for Food and Feed (RASFF). Results Certain needs were identified regarding the availability of rapid methods for the analysis of food additives. Conclusion Furthermore, there is need for the development of screening and high throughput methods for multicomponent analysis.