What is a tannin?is that the skin of the grape?

Question

What is a tannin?is that the skin of the grape?

Answer 1

They make thing brown.

http://en.wikipedia.org/wiki/Tannin

Answer 2

sesame paste

Tahini, or sesame paste, is a paste of ground sesame seeds used in cooking. Middle Eastern tahini is made of hulled, lightly roasted seeds. East Asian sesame paste is made of unhulled seeds.

Tahini is a major component of hummus bi tahini and other Middle Eastern foods. It is sold fresh or dehydrated.

Sesame paste is an ingredient in some Chinese, Korean, and Japanese dishes; it is a key ingredient of the Szechuan dish Dan dan noodles. Because East Asian sesame paste is made from unhulled seeds, it is more bitter than tahini, and higher in some nutrients.

Tahini is also used in Filipino cooking as an accompaniment with a number of beef dishes, including, but not limited to kaldereta and kare-kare.

Answer 3

Tannin, NOT tahini.  Tannin is tannic acid chemically: C76 H52 O46.  This comes from bark and several fruits.  it will stain most things to a varying shade of brown (or tan).

Tannic Acid is used to clarify wine and beer.  Other uses include using it as an astringent and septic.

It will show in a lot of water that has decaying matter in it.  the water can be "clean", but looks a yucky brown.

It can be found in the skin of grapes.