Depends upon what part of the body the "flesh" comes from.  Standard use for edible flesh in films has traditionally been GELATIN.  However if you have vegans they won't eat gelatin.  Gelatin - either KNOX unflavored OR even basic Jello can be made to look like real fleshy material that can be consumed with the appropriate Karo Syrup blood and such - just don't let any diabetics at it or they could go into shock with all that sugar.  But if left to dry out in the air AND if Jello or KNOX is mixed thoroughly with just enough hot water to dissolve it, it can be made thick and the left to dry in the open air till it becomes a bit rubbery.  Then that can be applied somehow and  used as the flesh that gets eaten.  AS you know you can mix colors of Jello to achieve a reasonable translucent flesh color - namely red, yellow will give you orange and then you can tone that down with green, etc......check your color wheel.  But yeah, gelatin (Jello or KNOX unflavored) work.

 

TonyDi