Jam was, according to Clara Oswald, made of strawberries. She used this as an example to ask the Eleventh Doctor what time was made of, to which the Doctor replied, "Not strawberries." (TV: The Rings of Akhaten)
The Fourth Doctor once asked if there'd be "strawberry jam for tea". (TV: The Power of Kroll)
Bakeries served cakes with jam in them. Amy Pond threw one such cake at an intruding Reptilodon, whose eyes were then covered in jam and custard. Rory Williams later pointed out that she had jam in her hair. (PROSE: Amy's Escapade)
After a test was done on it to find out the effects the sex gas's pheromones, the tested rat turned into what Owen Harper lightly called "rat jam". (TV: Day One)
In 2708, an insane resident of Tor-Ka-Nom murdered several jam merchants in the belief that jam whispered to people in their sleep. (COMIC: By Hook or By Crook)