Coat 9x5-inch loaf pan with non-stick cooking spray.
For mandarin orange layer: Dissolve orange gelatin in 1/2 cup boiling water in small bowl. Let stand for 10 minutes. Place dissolved gelatin, mandarin oranges and 1 cup evaporated milk in blender; cover. Puree for 10 seconds or until well blended. Pour into loaf pan. Refrigerate 30 minutes or until set.
For pineapple lemon layer: Follow process for mandarin orange layer substituting lemon gelatin for the orange and pineapple for the mandarin oranges. Pour mixture over mandarin orange layer. Refrigerate 30 minutes or until set.
For strawberry layer: Follow process for mandarin orange layer substituting strawberry gelatin and strawberries. Pour over pineapple lemon layer. Refrigerate at least 4 hours or overnight.
To unmold: Run point of knife around top of pan. Dip pan into a large bowl of warm water. Place serving platter on top of pan. Invert mold and platter together; shake gently to loosen. Gently remove mold. Cut into slices and serve.