Indeed there is "Eingemachtes" in contemporary German.
Duden defines "Eingemachtes" as follows:
(in Gläsern, Dosen u. Ä. aufbewahrte) durch Einmachen, Einlegen (2) in eine Lake o. Ä. haltbar gemachte Lebensmittel (besonders Obst).
Food being stored in jars, preserved by brine or another liquid conservative (esp. fruits).
Today this term usually refers to stewed fruit, or vegetables (e.g. cucumbers, beans, peas etc.) and is not used for jam or marmelade. Also related are the verbs "einmachen", or "einweckeneinwecken".
Interestingly the German word "Konfitüre" for jam is a direct loan word from French "confiture", which again translates to German "Eingemachtes". In addition the Swabian term "Gsälz" for jam is directly related to "Eingemachtes" as literally it means conserving something using salt ("Gesalzenes").