With regard to protein and lactose, it was observed that their values had an unexpected and significant increase after thawing. This fact may be related to the loss of water during the freezing and thawing process ( volatilization ), and sublimation, with increased infrared absorbance of protein at wavelength 5.7 microm, which was also observed in other studies and attributed to these properties. Furthermore, thawing of human milk may cause aggregation of the protein micelles, resulting in a variation of the protein content.