In a large bowl, cream shortening and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in the sour cream and lemon extract. Combine the flour, baking powder, baking soda and salt; add to creamed mixture alternately with buttermilk, beating just until combined. Fold in cranberries and poppy seeds if desired.
Pour into four greased 5-3/4x3x2-in. loaf pans. Bake at 350° for 40-50 minutes or until a toothpick inserted in the center comes out clean. Cool for 10 minutes before removing from pans to wire racks.