Apple as Forbidden Fruit?

Question

Is there a source for the commonly (mis)understood forbidden fruit being an apple? The Gemara Brachos (40a) identifies the possibilities of wheat, grapes, or figs:

דתניא אילן שאכל ממנו אדם הראשון רבי מאיר אומר גפן היה שאין לך דבר שמביא יללה על האדם אלא יין שנאמר (בראשית ט, כא) וישת מן היין וישכר רבי נחמיה אומר תאנה היתה שבדבר שנתקלקלו בו נתקנו שנאמר (בראשית ג, ז) ויתפרו עלה תאנה ר"י אומר חטה היתה שאין התינוק יודע לקרות אבא ואמא עד שיטעום טעם דגן The tree from which Adam, the first man, ate, Rabbi Meir says: It was a vine, as nothing brings wailing and trouble upon man even today other than wine, as it is stated with regard to Noah: “And he drank from the wine and became drunk” (Genesis 9:21). Rabbi Neḥemya says: It was a fig tree, as with the object with which they were corrupted and sinned they were rehabilitated, as it is stated: “And they sewed together fig leaves and made for themselves loincloths” (Genesis 3:7). They must have taken the leaves from the tree closest at hand, the Tree of Knowledge. Rabbi Yehuda says: It was wheat, as, even today, the child does not know how to call his father and mother until he tastes the taste of grain.

While the Medrash Bereshis Rabba quoted by Rabbenu Bechaye (Bereshis 3:6) adds as Esrog as the culprit:

וע"ד הקבלה אתרוג היה והוא נרמז בכתוב שנאמר ונחמד העץ להשכיל ותרגום אונקלוס ומרגג כי הוא פרי נחמד ומהודר וטבעו חם ומושל על השכל וכן תרגום הדר, אתרוגין. ומזה הזכיר בקללתו וקוץ ודרדר תצמיח לך. When looked at from a kabbalistic point of view, the tree was indeed the Etrog tree something which is hinted at in the words ונחמד העץ להשכיל, “and the tree was a desirable means to gain insights. Onkelos translates these words as ומרגג , “that the fruit was exceptionally beautiful and desirable.”

Answer 1

This article suggests a bunch of explanations for where the misconception came from. The suggestions are:

• Latin confusion: the Latin translation of the word "evil" (in Tree of Knowledge of good and evil) uses a word similar to the Latin word for apple
• Etrog as apple: Rav Soloveichik suggests since some sources indicate tapuach can mean an esrog, it got confused with apple (the usual translation)
• The generic fruit: The word apple used to be used as a generic term for fruit, and could have been used as the word to describe what was eaten in gan Eden
• Yaakov brought it in: Yitzchak when he smelled Yaakov (Bereishis 27:27) said he smelled "the smell of the field blessed by G-d", Rashi there says it smelled of gan Eden and elsewhere Rashi says a tapuach field (seems most likely to me).
• Blame the Targum: to Shir Hashirim 7:9 mentions the apple tree in gan eden

Answer 2

In Shir hashirim 2,3 it says explicitly >כְּתַפּוּחַ בַּעֲצֵי הַיַּעַר "like an apple in the forest". The Targum says

היכמה דיאי ומשבח אתרוגא ביני אילני סרק Just like the Esrog is fitting and glorified amongst the barren Trees. (Targum kesuvim is probably written by Rav Yosef the Amora as stated In sefer Yuchasin of Rav Abraham ben Samuel Zacuto written year רס״ד,Letter ג under "Gamliel.")

So the mistake is refering to an apple as the fruit found in gan eden from the word תַפּוּחַ which actually means esrog which is mentioned in Chazal as the fruit that Adam ate.

Also Chazal In Taanis 29b clearly refer to Gan eiden as the field of apple trees:

Bereishis 27,27 וירח את ריח בגדיו ויברכהו ויאמר ראה ריח בני כריח שדה אשר ברכו ה - And Yitzchak smelled the scent of Yaakovs clothes and he said "look my sons scent is that of the field that G-d Blessed."

Rashi then quotes Taanis 29b -∆ >כריח שדה אשר ברכו ה'" - שנתן בו ריח טוב וזהו שדה תפוחים כן דרשו רז"ל there was a good scent placed within him , and this is the sent of the field of apple trees(i.e gan eden).

It seems to be either

1. Someone (i.e Adam) Who ate from a "Field of apples" evidently ate an apple and this is a 5th opinion From Taanis 29b divergent from the Esrog,Fig,Wheat, or grapes.This is supported by the Verse in Shir Hashirim above, which continues וּפִרְיוֹ מָתוֹק לְחִכִּי "The fruit is sweet to my pallet," and esrogs are bitter tasting where as apples are sweet.

2. Every time it says תַפּוּחַ in chazal including Taanis 29b, it really means esrog and modern hebrew has used a mistaken term just like they call a livyatan a whale. Maybe esrog used to be sweet many years ago before we polluted the world. This is supported by the Targum above and Tosfos Taanis 29b: תפוחים. י"מ תפוחים כריח אתרוגים