An improved light reflectance method for the determination of enzymatic browning of apple slices has been described. Enzymatic browning rate parameter (DA440) of slices surface was determined from time-course measurements of visual region of spectrum and data at 440 nm of the difference in absorbance between freshly-cut and browning tissue. The paper defined the natural variability of fresh product (DA440 = 0.04) and the browning limit (DA440 = 0.15) for identification of the slices present in processing. The changes of DA440 parameter are compared with the colour difference parameter- DE* according to CIE 1976 L*a*b*. Nine varieties of apples: Granny Smiths, Early Redone, Royal Gala, Primarouge, Golden Delicious, Delbard Festival, F1orina, Ozark Gold, Jonnee were sliced in air or under water and their browning rates were compared. Different response of the cultivars to slicing in air or under water was documented. The studies have suggested cutting procedure directly in water also for application of inhibitors to cut surface.