Kaki-shibu (Persimmon Tannin) Sake Bag NO. 1 Scrap Fabric for Stylish Handmade Crafts Size: 78cm x 51cm, Hole 3cm x 5cm Although they have become less common now, these were dyed with persimmon tannin to enhance the preservation of the sake bags needed in the sake brewing process at breweries. The subtle color variations due to the chemical reaction between the persimmon tannin and alcohol, as well as the years of use, and the repaired areas of the fabric, all contribute to its unique character.