Tannins are separated into two classes&colon; hydrolysable tannins and condensed tannins. Barolos tend to be rich, deeply concentrated full bodied wines with pronounced tannins and acidity. Milk is thought to neutralise remaining tannins and reduce acidity. Chiantis tend to have medium-high acidity and medium tannins. The astringency of tannins is removed in various ways. Lemons contain numerous phytochemicals, including polyphenols, terpenes, and tannins. The resulting wine is fruity with very low tannins. They include hormone-mimicking phytoestrogens and astringent tannins. Boiling reduces the bitterness and the content of tannins and toxins. Most wines aged in charred oak barrels possess tannins absorbed from the wood. Lemon balm contains eugenol, tannins, and terpenes. In Argentina, Malbec becomes softer with a plusher texture and riper tannins. Nonfood products include essential oils, natural dyes, pigments, waxes, resins, tannins, alkaloids, amber and cork. Acorns also contain bitter tannins, the amount varying with the species. It is frequently associated with substances like tannins and alkaloids.