Mix vinegar, sugar, lemon rind in a saucepan. Tie cloves, cardamom seeds, peppercorns, saffron and mace in a little cheesecloth bag and toss into vinegar mixture. Cook to a boil and boil 5 minutes. Reduce heat and continue cooking, this time very slowly, another 5 minutes. While pickling liquid cooks, peel bananas and cut into slices about 1/2" thick. Pack slices into 5 sterilized half-pint jars. Discard spice bag and pour the hot liquid over the bananas. Seal and store for several days before using.