The image is of a section of table salt.

Thanks for all who guess the image of the food. The winner of prize for this week  is Anshu, who will get samples of Fairytale Brownies  mailed to their address. 

This food ingredient is the most essential and ubiquitous, only after water, for life. This simple ionic chemical compound consist of a metal and halide such as chloride. It gives a basic taste along with sweet, sour and bitter. This ingredient has been used in preserving food for thousands of years by method of pickling and curing, such as ham, bacon, smoked salmon. This food item comes from sea or in some cases from mines. To prevent iodine deficiency, this is often iodized, however excess can lead to increased risk of high blood pressure. What is this food ingredient?

Pic: D. Soric

The prize is samples of Fairytale Brownies mailed to your home. Fairytale Brownies  are premium all-natural handcrafted gourmet brownies.

Prize is mailed to one correct guess (or any if none correct) from readers within the United States. Comment before end of September 9, 2012 to win. The first correct guess receives two entries.