To avoid mushy marinated foods, always limit the amount of time that foods soak in the marinade. In general, foods with open-textured flesh, such as fish and seafood, need less than 45 minutes of soaking. Chicken breast break down after about 1 hour (skinless breast even faster), but thighs and wings can stand up to marinade for up to 2 hours. Foods with firmer flesh, such as beef and lamb, can spend several hours in a marinade without becoming mushy.
Also, ingredients such as yogurt, papaya, pineapple, and kiwifruit tenderize by enzymatic action. If your marinade includes any of these, marinate fish, seafood, and chicken for no more than 30 minutes, and marinate sturdier meats such as beef and lamb for no more than 24 hours.
** Asian Recipes