A good food pic starts with good light, composition and angle. A pic taken from the typical 45 degrees angle doesn't require any bokeh qualities of the lens. Unless your shooting angle is quite low to include the background of the restaurant / room.
Agree with Octarine. Lighting and composition are the two most important things in food photography (or any photography in general). That being said, if you do wanna pick a lens with good bokeh, I'd vouch for the Olympus 25mm f1.8. Personally I don't shoot on m4/3, but from my friends that do, they do love the focal length and the bokeh on the lens alot. Wide enough to give some context in the background, yet have enough background blur to bring focus to the subject (pun unintended).
If pay abit get Olympus 17mm f1.8, or leica. If pay even lesser get Pana 20mm f1.7 lah, legendary. And yes, used all these for artsy, filmlike hipster or high contrast imho looks better than my L and ART lenses too.