found it!
Mide el color del vino y de los polifenoles por espectrofotometría
IC-Intensidad de color, which means the intensity of the color of the wine, you welcome!
Haha I just went to a wine page and found that, I don't know, maybe you're more right. But wine can last for a long time, why would it be filtered? perhaps it can be pre-filter or refined before being bottle I don't know.