478. Series That Do Not Conclude With Amen
Brachos 1:17
Amen is recited after the bracha of Boneh Yerushalayim even though it is followed by the bracha of haTov v’haMeitiv since haTov v’haMeitiv was a later addition, added to bentching in the time of the Mishna. Boneh Yerushalayim is the conclusion of the basic brachos of bentching. Amen is not recited after the bracha Ahavas Olam because that is the conclusion of the brachos that precede the Shema. Similarly, whenever brachos are recited on an action, such as the brachos before reading the Megillah on Purim or lighting the menorah on Chanukah, amen is not said; doing so would constitute an interruption between the brachos and the action for which the brachos are being recited.
Brachos 1:18
Amen is not recited after the brachos on foods because those are only a single bracha each; amen is only recited after the last bracha in a series of brachos as a sign that we have reached the end of the series. Only then is reciting amen after one’s own brachos appropriate.