A stool culture is done to: 1  Find the cause of symptoms. 2  Find and identify certain types of organisms that are causing infections or diseases. 3  Identify a person who may not have any symptoms of disease but who carries bacteria that can spread infection to others. 4  Find out if treatment for an infection has worked as it should.
Meat may stay in the intestines for 24-72 hours and still depend on its type. Likewise, red meat in particular takes 1-3 days to complete the digestion process because of fat content and high protein, according to Lisa Cicciarello Andrews of University of Cincinnati.
Fish and meats take several hours to digest, as do proteins found in beans and legumes, because they are bound up with fiber. Soy protein also falls in this intermediate class of proteins in terms of digestion time. Milk protein (casein) takes the longest -- to seven hours to be fully digested. Best of luck!