What edible substances dissolve in saliva?

Starch will begin to be broken down into simpler polysaccharide molecules by salivary amylase. The enzyme lipase is also present in saliva but is usually inactive at the pH of saliva (around pH 6.2) and consequently will not act upon lipids (fats and oils) until it reaches the stomach where the pH is lower (and nearer to the enzyme's optimum PH.)