Food - Drink
The Best Ways To Keep Onions Fresh
While onions that are kept under very specific conditions and temperatures can stay fresh for up to a year, you might not need to meet those terms to keep your onions good for long enough. As long as you know how long you need to keep onions fresh, you can easily store them using two techniques to ensure they won't go bad before you need them.
Find storage areas for your onions that are dark, dry, and cool, and offer some airflow. Under these conditions, onions can stay fresh for up to a month, as the lack of sunlight will prevent the onions from sprouting, and the airflow will prevent the onions from absorbing too much moisture and becoming soft.
While the moisture of a refrigerator is not the optimal place to store most whole onions, it is a great place for cut or diced onions, and they will stay fresh for several days. If you don't want other foods in your fridge to absorb the aromatics of cut onions, you need an airtight container that also won't absorb any scents, like glass containers.