Hing, or asafoetida, emits a sharp odor even in sealed jars due to its volatile sulfur-containing compounds, which are potent and easily permeate packaging. These compounds are naturally present and responsible for its distinctive smell.
Hing's pungent aroma comes from a complex mixture of organic sulfur compounds, including disulfides and polysulfides. These compounds are highly volatile, meaning they readily evaporate and become airborne, allowing us to detect their odor. Even in a sealed jar, the concentration of these compounds can build up, and they can slowly diffuse through the plastic or glass, especially if the seal isn't perfectly airtight. Furthermore, temperature fluctuations can increase the volatility of these compounds, causing them to escape more readily. The intensity of the odor also depends on the quality and concentration of hing in the product. Some hing products are mixed with other ingredients like flour or gum arabic, which can slightly reduce the odor, but pure hing will always have a strong smell. The manufacturing process, which involves drying and processing the resin, also contributes to the formation and concentration of these odor-causing compounds.
To minimize the odor, store hing in an airtight container inside another sealed container, preferably made of glass or metal, and keep it in a cool, dark place. This double-layer protection will help contain the volatile compounds and prevent the smell from permeating your pantry.