To monitor banana surface (peel) roughness changes during ripening treatment, atomic force microscopy (AFM) as a novel and emerging technique was used in this study. The roughness of banana peel was studied using the arithmetic mean between peaks and troughs (Ra) and the root-mean-square roughness (Rq). It was concluded that with changing the ripening stages, the behavior of the roughness changes significantly. With advancing fruit ripening, the extending of the epicarp and the decrease of the surface (peel) roughness were found due to enlarging of fruit volume. The highest mean roughness was found to be at stage 1, Ra = 8.25 and Rq = 9.65 nm. Based on two-dimensional profile results, the surface (peel) roughness was affected strongly by studied different ripening stages. It was concluded that the peak values in the ripple profiles become smaller with advancing fruit ripening. However, the effects of noise in the profiles appeared to increase. So, in all the initial stages of banana fruit ripening, the noise was found to be minimal. Consequently, the AFM technique was found to be a promising tool for quantification of the peel roughness or glossiness and also could help in the quality control of banana fruit on the nanoscale.

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