Natural gut is produced by drying fibers extracted from a part of the cow intestine called the serous membrane, or serosa, which contains collagen designed to withstand the stretching and contraction of the intestine.

The earliest strings were made from cow intestines ("natural gut"), a reliable string but very expensive.

Preparation 503 - Chamomille, the German chamomile (Matricaria chamomila) flowers are sheathed in a cow intestine.

Then in the 14th century, the Italians began making wood rackets with long necks and a teardrop-shaped head strung with cow intestine.

In the middle sat a bowl of casings, the linings of cow intestines.

Ihmej: Ghameh (stuffed cow intestines)

In this Roadblock, one team member had to eat four pounds of a traditional Argentinian feast containing cow rib, pork sausage, blood sausage, cow intestine, cow udder, cow kidney and part of a cow's salivary gland.

But do it: eat the fried cow intestines.

The gut strings - which come from cow intestines and are not cat gut, as many people believe - range in price from $40 to $48, while synthetic strings are from $25 to $28.

Jochum also stated that BPI's product does not contain cow intestines or connective tissue such as tendons.