Back when I used to use dried garlic a lot (I'm talking way back, when fresh garlic was not readily available, like now, and before I grew it), powdered garlic seemed to give my foods a bad aftertaste, much more than the dried, minced garlic, even after I would powder that myself. I had no explanation for that, but maybe they just used sub-par garlic more often for the powdered? That minced garlic in jars, with preservatives in it has an even worse flavor - I used to be able to tell when a friend or a restaurant had used it! Fortunately, most restaurants now just buy peeled garlic in large amounts, and mince it themselves, though I know that pre-minced garlic is still out there. Fortunately, I only use fresh now, and is something I never run out of!