How we tested
The use of plants to tenderize meat dates back hundreds of years to the native peoples of what is now Mexico, who wrapped meat in papaya leaves. Both papaya and pineapple contain enzymes that break down collagen—the connective tissue that makes meat tough. These enzymes, papain (from papaya) and bromelain (from pineapple), are the active ingredients in bottles of meat tenderizer. We've dismissed these products in the past because they effectively tenderize only the outermost layer of a piece of meat—not much of an improvement for a thick, tough steak. But our ultra-thin veal cutlets were just the right thickness for the bottled tenderizer to penetrate completely.
To see if brand mattered, we gathered six tenderizers ("seasoned" and unseasoned varieties from three brands) and headed to the kitchen with several pounds of tough veal cutlets. Two brands contain papain, while one relies on bromelain to do the work. All of them worked equally well—neither the brand nor the type of enzyme made any difference. Should you opt for seasoned or unseasoned? While the extra spices aren't enough to ruin dinner, we'd just as soon do the seasoning ourselves.