Our Little Cups are "all-life stages" recipes and contain a higher mineral concentration to accommodate dogs of all ages. This increased nutrient density can lead to a natural oxidation process, resulting in what appears to be a darker color ring found within the cup. Since we do not use synthetic coloring or artificial additives, you are seeing the product doing exactly what it would do naturally had it been made in your own kitchen. All Health Extension products go through a series of up to 140 check points to ensure quality safety and palatability. We understand that this may be concerning and want to assure you that the darker color observed is cosmetic only.