Question about the pouch's ability to break food down (or not)
Ah Ha! "Does the new pouch secrete gastric juices to break down food?" There’s a question that has a Yes & No answer… my favorite kind… Secretions that would warrant the label- "Gastric Juices?" Not completely. "Digestive Juices?" Yes! Digestion starts just inside the lips and continues to the toilet. Saliva is a very powerful digestive juice actually. Couple of "experiments with early digestion?" Protein- take a small piece of beef jerky and keep it in your mouth. See how long you can Keep it like a "Chaw-of-Tobacco," over in one cheek. What starts as a hard leathery bit, will be all but mush In less than 30 minutes. Add a little chewing, And it’ll be mostly the consistency of a protein shake. Yes, some strands of tendon and sinew will remain tough as a rope. That’s the stuff that needs the Hydrochloric acids of "gastric juices" to liquefy it. For starches? Easier, clearer example of saliva breaking down starch. Take a plain ole- Saltine Cracker. Pop half of it in your mouth and chew, Notice the taste- salty and that "Toasted Flour" taste. Keep chewing it…..around the end on one minute, You’ll notice a sweet taste starting to develop. That’s the simple starches already breaking down into simpler starches and glucose. Yep, digested mostly before it ever leaves your mouth. Now, if it was just "Spit & Stomach Acid" That made up the whole of the "Digestive Juices" stock of "juices" that would be enough To deal with about half of the foods you eat. BUT- Every membrane from the mouth to the tail Is releasing some form of mucus. The esophagus lining produces sialomucin (A mucin [mucus type]containing sialic acid.) it also produces a neutral PH mucus as well, Along with many enzymes, all aimed at digesting the food Even before it hits the pouch. The pouch also secretes mucus. Swallow a chunk of un-chewed chicken or wad of soft bread And a quick case of the "foamies" will let you see- "Dam! That’s a lot of Slimy Snot coming from one little pouch!!" It will "easily clog up" if you don't chew well enough. And even at that- Soft bread can "getcha!" So yes, the lower stomach gastric juices don’t mix back with the food (in an RNY post-op****il they all meet up at the "Y in the Road." But long before the food gets there, it has been thoroughly "Slimed" with digestion. Chewing is primary to digestion And one of the things that must be done well to prevent that feeling of swallowing a cue-ball. The pouch primarily slowly squeezes well chewed, slimy food That is in the process already, of breaking down into absorbable liquid nutrients, through the little stoma at the bottom Where continued peristalsis, massages it on through the system. A simplified "fun" Overview of digestion, Is available in "flash form" at- Hopkins Digestive System
Just adjust the plumbing diagram to match your particular procedure. I’m a total nerd-geek when it comes to all of this. It’s like being a living part of the Discovery Channel. So short answer? Yes. And No. Sorry for the babble… Best Wishes- Dx
Capricious; Impulsive, Semi-Predictable 
For a series of Anatomical explanations (digestion included)
This link is pretty good-
Systems Overviews
It’s the one I used most often and is not flash, but inter-linked throughout… It’s been a while since I went looking at some of this stuff… Best Wishes- Dx
You got the procedure down very well. From the research that I've done, the digestive juices (bile, etc) is mostly generated at the bottom of the stomach which is bypassed after the procedure. The pouch created post-surgery is made more out of the muscular part of the stomach which creates the muscular contractions that make the food digest. The bile that chemically breaks down food conjucts later down in the small intestine where the bottom of the Y is created. I think this is why (not only because it aggreviates the small intestines) they tell us not to drink and eat solids at the same time initially because the little amount of digestive juices that may be there and saliva, doesn't get diluted with water.
