Question:
How long minimally and maximally would it take a piece of
fruit such as pineapple to reach the proximal end of the small intestine
after it was eaten? There seems to be varied opinions (20 minutes to
6 hours!) on the time fruit
takes to digest and pass through the stomach to the duodenum. It actually
has to do with forensic evidence in a well-known murder case in which the
victim had pineapple in the proximal part of the small intestine... which I
take to mean duodenum. No one seems to be able to give minimal/maximal time
for this process so I thought I'd shoot the question off to you all.
Replies:
Alejandro,
Well, if anyone is an expert on this subject, I am.
The stomach has three purposes; storage, mixing of gastric juices with the
food and emptying the contents into the small intestine. Knowing this, you
should begin to see the answer already. Speed of processing depends upon
the amount of food placed into the stomach [this determines the time to mix
and produce chyme], the amount of fat in that contents [takes longer to
make chyme] , the amount of fat that is in the duodenum as well as the
amount of material in the small intestine [prevents the pyloric valve of
the stomach from opening to expel more chyme], and the time of day and/or
the activity state of the body. More active the body will slow down the
stomach's actions as well as resting may slow it's activity as well. The
stomach mostly is involved with protein digestion and fat is not treated by
the stomach at all!
This explains the time differences. However, I did leave out the details.
NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.
