How does the aging process affect the color of Riesling wines?

With time, the Riesling wines may present some variations in color, with the producers of the wines turning from pale straw or greenish tones to richer golden tones. These changes in color are due to the appearance of secondary and tertiary aromas as well as to the oxidative processes which take place during bottle aging. Although not all Riesling wines will demonstrate dramatic color shifts, older vintages often develop a deep and sunset-like tone, suggesting their maturity and depth.