Roasted turmeric has a warmer, earthier, and slightly sweeter flavor compared to non-roasted turmeric, which is more pungent, bitter, and peppery. Roasting mellows the raw turmeric's intensity.
The difference in taste between roasted and non-roasted turmeric stems from the chemical changes that occur during the roasting process. Non-roasted, or raw, turmeric contains volatile oils and compounds that contribute to its sharp, somewhat bitter, and peppery flavor profile. The active compound, curcumin, is also present in its raw form.
When turmeric is roasted, the heat causes several transformations. The volatile oils mellow, reducing the pungent, raw edge. The roasting process also caramelizes some of the natural sugars present in the turmeric, resulting in a slightly sweeter and more nuanced flavor. The overall effect is a warmer, earthier taste that is less intense and more palatable for many people. Roasting can also enhance the bioavailability of curcumin, making it easier for the body to absorb.
If you find the taste of raw turmeric too strong, try lightly toasting it in a dry pan over medium heat for a few minutes before using it in your recipes. This will mellow the flavor and make it more enjoyable. Be careful not to burn it, as burnt turmeric will taste bitter.