Ptomaine Poisoning at the Greasy Spoon

Action against the Greasy Spoon Restaurant. P claims she was served spoiled baked beans by the Greasy Spoon on June 1 and got ptomaine poisoning as a result. At trial defendant offers to prove that the Greasy Spoon had a large pot of beans in the kitchen on June 1, that P was served from this pot, that at least 20 other Greasy Spoon patrons were served from the same pot, and that the Greasy Spoon received no other complaints. P objects. What ruling and why? What is the nature of the hearsay problem presented by this case? What result under the Federal Rules?