EDIT: The caption tag belongs to table and thus should only exist once. Do not associate a caption with each tbody element like I did:
First Half of Table (British Dinner)
| 1 | Fish |
| 2 | Chips |
| 3 | Pease |
| 4 | Gravy |
Second Half of Table (Italian Dinner)
| 5 | Pizza |
| 6 | Salad |
| 7 | Oil |
| 8 | Bread |
BAD EXAMPLE ABOVE: DO NOT COPY
The above example does not render as you would expect because writing like this indicates a misunderstanding of the caption tag. You would need lots of CSS hacks to make it render correctly because you would be going against standards.
I searched for W3Cs standards on the caption tag but could not find an explicit rule that states there must be only one caption element per table but that is in fact the case.