This sound is from Funnies Lucky Dip

Many cereals are trademarked brands of large companies, such as Kellogg's, General Mills, Malt-O-Meal, Nestlé, Quaker Oats and Post Foods. Similar equivalent products are often sold by other manufacturers and as store brands. This is a list of breakfast cereals.
See also: Stan Lee, and Looney Tunes and Merrie Melodies filmography (1940–1949).