The functional properties of milk protein concentrates (MPCs) are influenced by composition, processing conditions, and storage conditions. The objective of the study was to determine if front-face fluorescence spectroscopy (FFFS) could be used as a tool to understand the changes in MPCs during storage. Twenty MPCs with 4 different protein contents (70, 80, 85, and 90%) were collected from 4 different manufacturers and were stored at 2 temperatures (20 and 45°C) for 1, 2, 4, 8, and 12 wk. Three scans were performed on each sample to record the fluorescence spectra of tryptophan [excitation (Ex) 290/emission (Em) 305 to 450 nm], Maillard products (Ex 360/Em 380 to 480 nm), and riboflavin (Ex 380/Em 400 to 590 nm). Subsequently, the spectra were averaged and normalized by reducing the area under each curve to unity. The spectral data were then analyzed using principal component analysis (PCA). Multivariate statistical methods were applied to identify the variations during storage. Colorimetric values (L*, a*, and b*) were also determined. For each of the spectral data obtained, differences in the MPC samples stored at 45°C and 20°C were observed using PCA. After storage, there was a decrease in L* value and an increase in a* and b* values. MPCs exhibited a tryptophan fluorescence emission peak at 335 nm, Maillard emission peak at 432 nm, and riboflavin emission peak around 436. After storing the powders for 12 wk at 45°C, a decrease in peak intensities were observed in the tryptophan emission spectra and an increase in Maillard products emission spectra between 420 and 450 nm. Of the total variability, the first principal component (PC-1) took into account 99% (tryptophan data), 96% (Maillard products data), and 99% (riboflavin data) characteristics of the data. The results indicated that the FFFS, coupled with chemometrics, could be applied as a rapid and nondestructive method to monitor storage changes in MPCs.