The fruit (called granadilla) is hanging on a very thin, almost invisible fishing filament. The grey backdrop has a hole that is just a little smaller than the granadilla. This hole is hidden behind the fruit. From behind the backdrop, a P70 standard reflector illuminates the object and this light is reflected back to the grey backdrop. (The backdrop therefore always gets the same colour as the object!). The closer you place the backdrop behind the object, the faster the light falls off and the higher the contrast becomes.
From the right, a Picolite with the narrowest grids illuminates the fruit and a simple mirror reflects this light on the other side.