The paper presents the results of investigation on fruit’s skin of 6 apple varieties during shelf-live. The authors used to estimated colour the LAB system describing colour with hue, saturation and brightness values. The statistic analysis of variance was used to estimate the relationship between measure optical parameters and the changeability factor. The linear model was used to describe the variability of apple physical properties during shelf-live. This model can be useful to estimate the physical state of fruit and to predict the save periods of apple shelf-live for study varieties.