Shelf life modelling of photosensitive food: the case of coloured beverages

A new approach to shelf life modeling of photosensitive foods was developed taking into consideration the example of a saffron-containing yellow beverage highly prone to oxidative photobleaching. The beverage was exposed to different light levels at increasing temperatures. During exposure, samples were analyzed for bleaching rate, pigment content, and pigment degradation products. The results obtained clearly showed that shelf life 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, the concomitant exploitation of the accelerating effects of both light and temperature was used to develop and validate a simple model correctly predicting the shelf life of the beverage under actual storage conditions. The methodology proposed may allow solving of the difficult task of predicting shelf life of photosensitive foods usually marketed in the presence of light.