pTAN:IRPs

The Protein-Precipitable Tannins to Iron-Reactive Phenolics ratio (pTAN:IRP) is a useful metric for understanding extraction in skin-macerated wines. Iron-Reactive Phenolics extract readily from grape pulp whereas Protein-Precipitable Tannins require alcohol, temperature, and movements to extract from the skins and seeds. Because of this, high production wines tend to have lower ratios whereas reserve-tier wines generally have higher ratios. pTAN generally account for 50-55% of extractable IRPs in skin-macerated wines. This ratio will fluctuate depending on fruit quality, most notably decreasing with hotter climates. Protein-Precipitable Tannins: Iron-Reactive Phenolics (pTAN:IRPs) <0.3 is low-efficiency extraction typical of shorter macerations and larger production volumes. 3-0.4 is a moderately efficient extraction typical of middle-tier wines. 4-0.5 is a highly efficient extraction typical of premium and reserve wines. >0.5 is heavily extracted typical of powerful win