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Name: Susan
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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.

Steve Sample



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