I use your black cumin oil. I wonder whether I could use oil from the vial which was opened 6 months ago, i.e., after what time of vial opening oil won’t change its properties.
Dear Madam,
If oil has not changed its taste and colour and if its shelf life has not expired, you may use it. Black cumin oil is cold pressed oil and if it is kept in a warm and sunlit place for a long time it may get rancid. Throw it away if it has changed its taste.
Best regards