Learning to use new and unfamiliar ingredients is one of the great joys of exploring a different culture's cuisine. The exuberant spicing of Indian cuisine, the Middle East's use of fruit in savory dishes and Southeast Asia's fresh, bold flavors are all vastly different from traditional American cooking. Unfortunately, ingredients for those cuisines can sometimes be hard to find. For example, many Southeast Asian dishes call for fresh or powdered galangal. It can be found online, or you can improvise substitutions.
Galangal is a close relative of ginger, and they grow in a similar fashion. They're harvested as rhizomes, swollen and fleshy roots similar to tubers. Galangal's skin is thinner and shinier than ginger's, and it's hard and woody -- like lemongrass -- whereas ginger is relatively soft and juicy. Galangal is similar to ginger in flavor, but without fresh ginger's distinctively fresh hint of lemon. Instead, galangal has a sharp, peppery note with a hint of pine forest. Asian grocers sell it fresh, frozen, dried in slices and sometimes as jars of powder or paste. As with ginger, galangal powder is very strong but lacks the subtlety and distinctive flavors of the fresh variety.
Galangal Powder Substitutes
There's no single direct substitute for galangal powder, but ginger comes closest. Most recipes call for only a small amount of galangal, and you can substitute ground ginger directly. If your recipes uses both ginger and galangal powder, increase the ginger slightly but don't replace the full amount of galangal. In recipes where galangal provides a featured flavor, it's worth the effort to replicate its flavors more closely. Try adding a tiny pinch of clove to the ginger powder for its aroma, a small amount of ground black pepper or Szechuan pepper to replicate galangal's peppery bite, and a hint of ground cardamom or juniper berry to suggest galangal's pine-like notes.
If you ordinarily use galangal powder because of its long shelf life, you might consider replacing it in your pantry with dry galangal. It's usually sold as thin slices in an airtight package. You can keep it in your pantry in a zipper-seal bag or sealed jar to keep it from absorbing moisture. Galangal powder quickly loses much of its volatile aromatic compounds, but dried galangal retains more of the flavor of the fresh root. Pulverize pieces in your spice grinder and use the freshly ground powder in your favorite recipes, or reconstitute the slices in a small amount of water and use them in place of fresh galangal.
Fresh, Frozen or Paste
If you locate an online supplier or Asian grocery that sells fresh or frozen galangal, or galangal paste, seize the opportunity to stock up on the real thing. You'll need a fine plane-type grater to shred the fresh, woody root, or else slice it thinly with a very sharp knife and mince it or pulp it in a mortar and pestle. Don't get it on your clothes because like turmeric, another close relative, it can stain. Use approximately a half-inch of the root for every teaspoon of powder your recipe calls for. Frozen galangal is used the same way. Galangal paste is fresh galangal that's machine-ground and mixed with stabilizers or antioxidants to keep it from spoiling. Use a rounded teaspoon of paste for every teaspoon of powder in your recipe.