This idea is not rare, but until now the science of proper hydration while eating has not been adequately explained. Now that it has, lets take a look at a technique for it.
Digestive enzymes are already created in our mouths in preparation of food intake. It is the digestive enzymes that require an aqueous environment in order to move and reach the substances to be mined. Thus, every bite should be accompanied by a tiny, but sufficient, water or liquid. The goal is to chew up the gross materials, and then add that bit of water to allow the food's consistency to be mushy.
Then the digestive enzymes can literally piggyback along with the prepared mush into the stomach, where stomach acids won't have to labor tiredly in their process of preparing the food for the small intestines. Basically, the more you prepare your food for digestion, the easier it is on each and every digestive organ.
Fletcherizing is the slowly and thoroughly chewing of food. This makes sure that all the juice and contents of the plants, which are stored behind the tough-to-digest cellulose, are tapped into. The fiber - cellulose - can then be discarded or swallowed.
Unfortunately, not many people are aware of the benefits of Fletcherizing, as well as, they don't have "enough time" to slowly and thoroughly chew their food. For people like that, there are alternatives.
Fresh Juices and Smoothies
Juices are different than Smoothies. When you prepare a juice, you remove all the fiber out of the vegetables and fruits. When that is done, the stomach doesn't have to labor on digesting the fiber, and instead, the high water and nutrient juice can skip stomach digestion and arrive for immediate absorption at the small intestines.
On the other hand, a smoothie has all the fiber, which is good for many reasons, but it requires digestion by the stomach before allowing it to continue to the small intestines for absorption. Smoothies should never be gulped down like water or juice, as it requires a bit of swooshing around in the mouth in order to coat it with digestive enzymes.