- 1). Check the lettuce before you buy it, to make sure it is fresh. You cannot keep lettuce fresh if it was not fresh when you acquired it. Look for firm leaves with no discoloration.
- 2). Put the lettuce in a plastic bag at the store or market, if it is not in one already.
- 3). Place the lettuce -- still in the plastic bag -- into the crisper drawer. Check the setting for that section of the refrigerator, to set it for low humidity.
- 4). Store lettuce in a crisper without ethylene gas-emitting fruits like apples. The CDC states that the gas will cause brown spots to develop on the lettuce leaves.
- 5). Keep the lettuce in the crisper for the proper amount of time, based on its variety. Iceberg lettuce is the most hearty variety. It can last two weeks in a crisper. Endive is the most delicate; it lasts only four days. All other lettuces fall in-between those times.
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