In a bowl, combine mustard, oil, vinegar, salt if desired and turmeric; gradually add milk until smooth. Refrigerate. In a large resealable plastic bag or shallow glass dish, combine soy sauce, ketchup, sugar, molassas and garlic. Add pork; seal or cover and refrigerate for 4-6 hours, turning occasionally. Place the pork in a shallow roasting pan; discard marinade. Bake, uncovered, at 350° for 40 minutes or until a meat thermometer reads 160-170°. Let stand for 5 minutes. Slice pork; sprinkle with sesame seeds if desired. Serve with the mustard sauce.