Glycemic Index Help

Why does boiling pasta longer than 4-7 minutes increase the pasta's glycemic index rating?

I just got home from Whole Foods, where I had gotten papardalle pasta (among other things, of course). On the package, it says: "The more you cook your pasta, the higher the glycemic-index rating. Please test your pasta frequently, and become accustomed to eating pasta al-dente, as they do in Italy". I searched on the internet and found sites that say that the GI rating increases with more boiling, but none say why? I would have thought it would be the opposite, thinking that the starches would boil out of the pasta the longer it boiled?

Public Comments

1. Just like soaking grain in hot water breaks down starches to make the sugars required for alcohol fermentation, the starches in pasta break down in to sugars that raise the GI.
2. Something that affects glycemic index is how fast the thing is absorbed. If it is in smaller "peices" then it will absorb faster than if it were big peices. Think of surface area. So when you boil your pasta the stuff is getting softer and it is expanding, the water is getting inside, your body has more access to break it down. When it is still hard then it will take longer to break down. Another interesting thing.. an unripe banana is lower on the scale than a ripe one. An unripe one is mostly starch, and as it ripens the starch converts to sugars. (don't get my banana example confused... the pasta starch is not converting into sugar. it will do that in your body)
3. I don't know, but this explains why I like my pasta cooked on the longer side. Nothing I ever like is healthy, this sucks.
4. Cooking pasta longer than al dente causes the starch/gluten matrix to weaken which makes it more digestible as a carbohydrate and thus releases more sugar faster into the blood stream from the intestines. More starch is released in the digestive process from highly cooked pasta than from al dente where the stomach has to work harder to break down the starch/gluten structure. Gluten is a protein and thus digests differently than starch.
5. Because the starches in the pasta begin to break down during the cooking process. The longer it cooks the more it breaks down. (Note:pasta continues to cook even after it's removed from heat.) By the time it hits your system (mouth) it has already began to turn from a complex carb (takes a while to move through your system ie. breakdown; turn into sugar) into a simple carb (almost completely broken down). Simply put it turns into sugar faster, which raises glucose levels faster . But the starch never actually leaves. You just delay your bodies processing of it. This is a good think especially for diabetic pasta lovers!
6. Heat breaks down the complex carbohydrates to simpler molecules.