There are no recommended standard angles for food or for the number of light sources.
Often, there is a very large softbox (diffused light source) which is designed to mimic a natural (i.e., sun coming through a high north window) light source. Lamps/flash are preferred by many studio photographers because the color temperature and output is consistent throughout a shoot. Flash units are often used because they generate less heat - useful when photographing food. In the architectural model work we did in the studio it was almost all hot lights.
Now you have ambient overall lighting covered. The next questions are how big is what you're shooting and what to do you want to emphasize? So, there's generally at least one "key" light that is "flagged" (to keep the light off parts of the scene you don't want illuminated). Instead of another light, depending on the effect you're looking for, you might have one or more "bounce" cards that take the ambient light and reflect it into the scene to reduce contrast.
As I alluded to earlier, if you don't have a view camera so that you can really master depth of field effects, you want to stop down as far as you can and make sure that everything in the scene is tack sharp. Then you can go back into Photoshop (or similar) and add the depth-of-field focus effects after, if desirable.
I agree with you that use a standardized reference color target makes an enormous amount of sense, as is using a white card to set white balance - especially when you are shooting film. These days, however, the auto-correct feature in many programs these days is so good that it'll take care of 95% of situations. Without a recognizable iconic color in the scene (we used to shoot a Kodak box on the first frame of every roll for this purpose) then the most important things in the image (technically):
a) no motion from the camera
b) tack-sharp focus, at least on the key element(s) of the scene
c) a pure black (RGB 0,0,0) somewhere in the scene
d) a pure white (RGB 255,255,255) somewhere in the scene
e) clean whites (i.e., whites without a noticeable color cast)
Of course, any or all of these "rules" can be broken - if and when you know what you're doing and WHY you're breaking them.
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clay - http://www.thechocolatelife.com/clay/