Pour the vinegar in the milk and allow to rest for about 5 minutes. Then add the vanilla essence and mix well.
Combine the egg and oil or butter. Combine all the liquid mixtures and pour into the oat and bran.
Sift and combine the flour, baking powder and baking soda. Add the nutmeg.
Add the flour and raisins to the oat and bran liquid mixture. Mix quickly until moistened.
Drop batter into greased muffin pans, filling each ⅔ full. Bake in a preheated oven 424F for about 20 minutes.