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This work was addressed to study the chemical stability of coffee brew derivatives as a function of water activity(a w ) and storage temperature. To this purpose, coffee brew was freeze-dried, equilibrated at increasing a w andstored for up to 10 months at different temperatures from –30 to 60 °C. The chemical stability of the sampleswas assessed by measuring H 3 O + formation during storage.Independently on storage temperature, the rate of H 3 O + formation resulted to be considerably low only when a wwas reduced below 0.5 (94 % w/w). Beyond this critical boundary, the rate increased reaching a maximum valueat circa 0.8 a w (78 % w/w). Further hydration up to the a w of the freshly prepared beverage significantly increasedchemical stability. It was suggested that mechanisms other than lactones’ hydrolysis, probably related tonon enzymatic browning pathways, could contribute to the observed increase in acidity during coffee staling.The temperature dependence of H 3 O + formation resulted to be well described by the Arrhenius equation in theentire a w range considered. However, a w affected apparent activation energy and frequency factor. These effectswere described by simple equations which were used to set up a modified Arrhenius equation. This model wasvalidated by comparing experimental values, not used to generate the model, with those estimated by the modelitself. The model allowed efficient prediction of the chemical stability of coffee derivatives on the basis of onlytheir a w and storage temperature.6. Manzocco L., Kravina G., Calligaris S., Nicoli M.C., 2008, Shelf life modelling of photosensitivefood: the case of coloured beverages. J. Agric.Food Chem., 56 (13) 5158-5164.A new approach to shelf life modelling of photosensitive foods was developed taking into consideration theexample of a saffron-containing yellow beverage highly prone to oxidative photobleaching. The beverage wasexposed to different light levels at increasing temperatures. During exposure, samples were analysed forbleaching rate, pigment content and pigment degradation products. The results obtained clearly showed that shelflife testing of light-sensitive foods must take into proper account the effect of light. In addition, for these foods,shelf life models based on the sole accelerating effect of temperature may be misleading. By contrast, theconcomitant exploitation of the accelerating effects of both light and temperature was used to develop andvalidate a simple model correctly predicting the shelf life of the beverage under actual storage conditions. Themethodology proposed may allow solving the difficult task of predicting shelf life of photosensitive food usuallymarketed in the presence of light.7. Nicoli M.C., Manzocco L., Calligaris S., Chapter 11. Packaging and the shelf life of coffee. InFood packaging and shelf-life (a cura di G. Robertson, ), Taylor and Francis, in stampa.8. Cdrom FoodLife: Supporto per la stima in tempi rapidi della vita commerciale di conservesott’olio e prodotti da forno. Il CD-ROM e l’allegata guida all’uso sono stati realizzatinell’ambito del Progetto Novimpresa di Area Science ParkSISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it500