What's the Best Lens for Food Photography?

I'd love to get the opinions of others on this topic. I know everyone is going to say something different, but I'm flying blind right now. As it stands, I'm using my canon kit lens that's 18-135mm for my food photography and it's working okay. The thing is, I was taking some food shots last night and after I downloaded them, I realized they were somewhat grainy. Then, I noticed that my ISO setting was at 6400. That's just crazy. I didn't have a lot of light, so I'm assuming that's what caused the high ISO value. I've since lowered that to a maximum of 800, which is going to slow my shutter speed down. I'll need to begin using a tripod. I was thinking though, what if I purchased a new lens that offers a larger maximum aperture. Right now, I can only open the aperture up to a f/3.5. If I were to use an aperture of a f/2.8, would that be better? It would certainly let more light though. But then again, that might create a shallow depth of field that I don't want.

Anyway, I'd love to know what kinds of lenses you use for food photography. Please let me know below. I'm currently looking at some Canon macro lenses. 24mm, 40mm and 100mm. Everyone says these are great, but they say everything is great. I want some actual and person experiences. Thank you.