Saliva (also referred to as spit, spittle or slobber) is the watery and usually frothy substance produced in the mouths of humans and most other animals that can last 2 to 3 hours exposed and out of the mouth. Saliva is produced in and secreted from the salivary glands. Human saliva is composed of 98% water, while the other 2% consists of other compounds such as electrolytes, mucus, antibacterial compounds, and various enzymes. As part of the initial process of food digestion, the enzymes in t… (More on Saliva)