The Rambam (Hilchot Deot 4:8) recommends eating חִלְתִּית in cold/rainy seasons as a warming food alongside mustard. The commentary in Kovetz al Yad haChazak notes that the Sefer Lashon Chachamim identifies this word as identical to the Arabic/Turkish קאוו"י (qahwe — coffee): a seed that warms the body, consumed in Arab lands. Supporting sources cited: Mishnah Uktsin 3:5, Niddah 51 (with Ra'avad commentary noting the unpleasant smell yet its use as a food additive), and Tosafot Yom Tov (Tevul Yom ch.1) citing Rashi in Shabbat that this substance is sometimes eaten in cold countries. The Kovetz also notes that Rambam did not include the medicinal remedies mentioned in the Talmud in these chapters, since Rav Shimshon (R"Sh) wrote that one should not follow them lest one have doubts about Chazal.

A notable early halachic-lexicographic identification of coffee in Rishonim-era terminology. The connection: חִלְתִּית = קאוו"י = qahwe (Arabic for coffee). Supports the view that coffee was known to medieval Arab culture and that the Rambam's dietary advice may have included it. Cross-references: Mishnah Uktsin 3:5, Niddah 51, Tosafot Yom Tov Tevul Yom 1, Rashi Shabbat.

Elliot Horowitz, "Coffee, Coffeehouses and the Nocturnal Rituals of Early Modern Jewry" (AJS Review, 1989, pp.17–46) argues that the timing of the spread of the Shavuot all-night custom correlates with the introduction and proliferation of coffee in Jewish communities in early modern times.

OU Torah Dalet Amot of Halacha (R. Enkin, 2025). Cited as a "compelling theory" — academic source, not a halachic ruling.

Tzahlon writes in Otzar HaChaim that חלתית is a seed (זרע א') that warms the body, and those who eat it hear a ringing in their ears called קאוי — a phonetic identification with קאווע (coffee). Eliezer Brodt surveys this identification. The question has potential halachic ramifications wherever חלתית appears in rabbinic texts (bracha, Pesach, medical rules).