Bicarbonate of Soda and White Vinegar are both great natural deodorisers.
Placing an open dish of Bicarbonate of Soda in a cupboard, bathroom or fridge will neutralise odours. When it needs replacing (every 3 months), pour the used powder down the drain, followed by 100ml White Vinegar to help keep drains clear.
To deodorise the air from cooking or smoky smells, simply spray the area with White Vinegar. Don't worry - the vinegar odour will dissipate, leaving you with a fresh, clean smell. Adding your favourite essential oil will also fragrance the air!