Lettuce has a very short shelf life compared to most other vegetables, especially varieties with more tender leaves. The ideal is to store it in a cold, humid environment with minimal air circulation (the vegetable drawer of the refrigerator seems to have been designed to cover this function). Learn some tricks to keep lettuce fresh for a week or even longer.
Steps
Part 1 of 2: Simple Method to Store Lettuce
Step 1. Remove the core from the lettuce head
Some varieties of lettuce, such as iceberg, romaine, and all those with a leathery core, last longer if the core is removed. Remove it with the knife or tap it hard against the cutting board and then twist it to detach it with your hands.
Core only lettuce varieties that have firm, firm leaves
Step 2. Wrap the lettuce in kitchen paper
Wrap the whole head or individual leaves arranged in layers between two sheets of soft absorbent kitchen paper. The paper will absorb excess water, but at the same time it will keep the lettuce moist.
- If the lettuce looks dry, moisten the paper with a little water.
- If the lettuce is very wet, wrap it in paper, then wring out the paper and wrap it again with the same damp paper.
- If you bought bagged lettuce, dry the leaves with the salad spinner.
Step 3. Store the lettuce in a plastic container
You can use a zip lock bag, a food container with a lid, or a salad spinner. If using a bag, let some of the air out before sealing it (being careful not to damage the leaves when you squeeze it). If you are using a container, at least half fill it. The greater the amount of air in the container, the faster the leaves will blacken.
If you let all the air out and seal the container completely, the lettuce may take on an unpleasant odor due to poor ventilation. This is why it is useful to leave some air in the bag or container slightly open, especially if the leaves are loose or if the refrigerator temperature is not too cold
Step 4. Return the lettuce to the vegetable drawer
Being the coldest part of the refrigerator, it is the ideal place for leafy vegetables. Depending on when it was picked, the lettuce should be able to last up to 3-7 days. The iceberg variety can last up to two weeks. If you grew lettuce in your garden or bought it directly from the producer, it may last longer.
- Make sure other foods in the refrigerator don't crush it, or the leaves will be damaged and may rot.
- Do not put lettuce in the same drawer that you store apples, pears or tomatoes, as they release a large amount of ethylene which could cause it to rot.
Step 5. Check the container
If a lot of condensation has formed on the walls, adjust the refrigerator settings or the fans that allow air to pass through the vegetable drawer to reduce the degree of humidity (also, if necessary, empty the container of excess water). If you see that ice has formed in the drawer or on the lettuce leaves, increase the temperature in the refrigerator.
Part 2 of 2: Extend the Life of the Lettuce
Step 1. Exhale into the lettuce container
Carbon dioxide delays the process that causes leaves to blacken and prolongs their lifespan. A simple method of introducing carbon dioxide into the container is to blow through it briefly before closing it. For hygienic reasons, use this method only if the lettuce is intended for personal use.
Carbon dioxide is only beneficial if the lettuce is already cut, not the whole head
Step 2. Use a more powerful source of carbon dioxide
With this trick to introduce carbon dioxide into the lettuce container you can extend its shelf life by up to 5 days. Proceed like this:
- Freeze one teaspoon (5 ml) of white wine vinegar in a small container, for example in an empty glass jar.
- Pour a teaspoon (5 g) of baking soda over the frozen vinegar.
- Do not close the jar, simply cover it with several layers of blotting paper and secure the paper with a rubber band.
- Return the jar to the container with the lettuce, making sure it stays upright. The vinegar will thaw slowly and when it comes into contact with the baking soda it will trigger a chemical reaction that releases carbon dioxide.
Step 3. Put the vacuum-packed iceberg lettuce in a glass jar
If you have a vacuum machine, you can use it to extend the life of the lettuce. The iceberg variety will keep fresh for up to two weeks. Romaine lettuce will last up to 7 days. This method is not suitable for varieties with soft leaves.
- You can mimic the vacuum machine with a much cheaper (but less effective) tool, namely a hand pump. Pierce the lid of the jar with a thumbtack, cover it with electrician's electrical tape, and use the pump to push the air out through the electrical tape.
- Use a jar and not a food bag, or the lettuce leaves will crush.
Advice
- Lettuce wilts when it loses water. To restore vigor to the leaves, leave them immersed in a bowl filled with frozen water for 30 minutes.
- Washing "pre-washed" lettuce does not make it safer to eat. In fact, washing it risks introducing new contaminants that may be present on the kitchen surfaces. For the same reason, you shouldn't wash lettuce that hasn't already been pre-washed until you're ready to eat it so the bacteria don't have time to multiply.
