The famous antioxidant from grape skins, concentrated in red wine because reds ferment with skin contact. Hyped in the 2000s for cardiovascular benefits at doses far higher than wine actually delivers: a glass of red contains roughly 1 mg, the studied doses were ~250 mg. Still beautiful chemistry. Just not the something the magazine articles promised.
The aldehyde that makes cinnamon taste like cinnamon, roughly 90% of cinnamon bark oil by volume. Triggers TRPA1 (the "wasabi receptor") at high doses, which is why Red Hots burn and a cinnamon stick steeped too long in mulled wine turns acrid. Cassia cinnamon (the common grocery-store kind) carries more than the milder Ceylon variety.
The clove note, a phenylpropanoid that shows up wherever a recipe calls for clove, allspice, or nutmeg, and in rye whiskey through oak-barrel extraction. Anesthetic at high concentration; dentists used clove oil for centuries before lidocaine. The numbing sensation on the tongue from biting a whole clove is eugenol blocking nociceptor signaling at the contact point.
Red wine, brandy, citrus and whole spices, heated to 70°C. It is not boiled: ethanol boils at 78.4°C, and a simmer would drive it off fast. Cinnamaldehyde, eugenol and anethole infuse into the wine's tannin structure. A Central European Christmas-market staple.
PROVENANCE
The oldest spiced-wine recipe survives in De Re Coquinaria, the Roman cookbook attributed to Apicius and compiled around the 4th century AD; Roman conditum paradoxum used wine, honey, pepper, mastic, saffron, and roasted date stones. The drink evolved through medieval European herbal-wine traditions (hippocras in France, ipocras in England) into the modern Christmas-market staple. The Germanic 'Glühwein' specifically refers to the German Christmas-market version with cinnamon, cloves, and star anise. Sweden's glögg adds vodka and raisins.