Pu-erh tea is a post-fermented tea produced from large-leaf green tea in Yunnan, China. It can be compressed immediately as raw pu-erh or fermented for months prior to compression as ripe pu-erh. Ripe pu-erh undergoes wet piling for 6-12 months, where the leaves are piled, wetted, and mixed with microflora including Aspergillus, Penicillium, and yeasts. Pu-erh is believed to provide health benefits such as reducing blood cholesterol and having antimicrobial properties. Properly aged pu-erh improves in taste over time due to secondary oxidation and fermentation during storage.