Use of images in shelf life assessment of fruit salad

Fruit salads stored for different lengths of time as well as their images were used to estimate sensory shelf life by survival analysis. Shelf life estimates obtained using fruit salad images were longer than those achieved by analyzing the real product. This was attributed to the fact that images are 2-dimensional representations of real food, probably not comprehensive of all the visual information needed by the panelists to produce an acceptability/unacceptability judgment. Images were also subjected to image analysis and the analysis of the overall visual quality by a trained panel. These indices proved to be highly correlated to consumer rejection of the fruit salad and could be exploited for routine shelf life assessment of analogous products. To this regard, a failure criterion of 25% consumer rejection could be equivalent to a score 3 in a 5-point overall visual quality scale.

Food images can be used to assess product shelf life. In the case of fruit salads, the overall visual quality assessed by a trained panel on product images and the percentage of brown pixels in digital images can be exploited to estimate shelf life corresponding to a selected consumer rejection.