Can saliva change the way our food tastes? Does it affect our cooking? In our Season 16 finale, reporter Jacklyn Kim digs into the unexpected ingredient that we end up adding to every meal. Proof will be back later in May with a 6-part miniseries on the history of cocktails!  Until then, stimulate your taste buds and break out the cast iron with the Test Kitchen recipe for Cast Iron Margherita Pizza.  Get a 14-day free trial for an America’s Test Kitchen digital subscription here. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info. Learn more about your ad choices. Visit megaphone.fm/adchoices