Cream butter and sugar together. In a separate bowl, dissolve soda in lemon juice. Mix in eggs and vanilla. Beat butter mixture and egg mixture together. Add flour and salt. Do not over mix. Gently fold in apples. Mix crumb ingredients, cutting in butter to get a coarse crumb texture. Spoon half of batter into greased stoneware loaf pan. Sprinkle with half crumb mixture. Spoon in remaining batter and sprinkle with remaining crumb mixture. Press crumbs gently into surface of batter. Bake at 190ºC or 1 hour 15 minutes or until a cake tester inserted in center comes out clean. Cool slightly in pan. Remove bread from pan