Thanks for reaching out! As you know, Vital Proteins only uses the highest quality natural ingredients. Because we use real natural ingredients, color may change throughout shelf life. Regarding the unflavored Collagen Peptides w/Vitamin C and hyaluronic acid product in particular, we use high quality natural Vitamin C in this product. Over time, Vitamin C can change colors and brown (Maillard reaction) over time. Depending on the batch of our materials, this rate of color transition can happen at different speeds. This browning in the Vitamin C is completely normal and does not impact the taste, product quality, or safety of this offering. You can still enjoy your unflavored Collagen Peptides w/Vitamin C and hyaluronic acid to its fullest!