To preserve wheat, add kasoori methi ( Dried fenugreek leaves ) to it and store in an airtight container.Wheat will not go bad for a longer period.
To preserve Tamarind, you have to clean and remove the strings and seeds. Then roll them into small balls store in an ceramic or clay vessel. If you add a little rock salt to that it will stay for a longer period.
If you put in a little peppercorns in to the vessel which you use for storing the ghee, the ghee will not get rancid or spoiled.
While storing eggs do remember to put the broader part of the eggs upwards facing you. The eggs will stay fresh longer.
While storing cashewnuts add a clove or two in o the bottle. The cashewnuts will stay fresh longer.
To save coconut oil from getting rancid or smelly add a piece of jaggery (achu vellam) in to the jar containing oil.