Does Watercress Need to Be Washed Before Eating?

According to the U.S. Food and Drug Administration, washing produce thoroughly is one of the most effective ways to reduce the risk of foodborne illness. This is especially true for watercress, and yes, watercress needs to be washed, even if it comes in a pre-packaged bag.

Quick Summary

This article explains why watercress, including pre-packaged versions, must be washed to remove dirt, bacteria, and parasites. It details the proper cleaning techniques and storage methods for both wild and commercially grown watercress to ensure maximum freshness and safety.

Key Points

• Always Wash: All watercress, including pre-packaged products, should be washed to remove potential contaminants.

• Wild Watercress Risk: Never eat wild watercress raw, as it can be contaminated with the liver fluke parasite; always cook it thoroughly.

• Thorough Rinsing: Use a bowl of cold water to soak and agitate the watercress, changing the water until clean, to remove dirt and grit effectively.

• Dry Completely: For raw consumption, dry the watercress with a salad spinner or paper towels to prevent wilting and prolong freshness.

• Store Unwashed: For longer storage, keep watercress unwashed and dry in a damp paper towel or in a cup of water in the fridge, washing only before use.

• Cross-Contamination: Always wash your hands before and after handling watercress and use clean kitchen tools to prevent cross-contamination.

The Importance of Washing All Watercress

Many people assume that produce labeled as "pre-washed" or "ready-to-eat" doesn't require further cleaning, but this is a dangerous assumption, especially with leafy greens like watercress. The delicate leaves of watercress can trap dirt, grit, and pathogens from the water it grows in, and commercial washing processes are not 100% effective. Recalls involving bagged salads contaminated with E. coli in recent years serve as a stern reminder that relying solely on manufacturer washing is a risk. Wild watercress, in particular, poses additional risks, including exposure to parasitic organisms like liver fluke, which is a major health concern if not properly addressed. Therefore, washing watercress is a critical step in preparing this nutrient-dense vegetable for consumption.

Potential Contaminants on Watercress

To understand why washing is so important, it helps to know what you might be washing off. Watercress can carry a variety of contaminants, depending on its growing environment:

• Soil and Grit: Even commercially grown watercress can retain small amounts of soil and grit, especially near the base of the stems, which can be unpleasant to eat.
• Bacteria: Like any other fresh produce, watercress can be contaminated with harmful bacteria, such as E. coli or Salmonella, at various points from the farm to the store.
• Parasites: For watercress harvested from the wild, the biggest risk is the liver fluke, Fasciola hepatica. This parasite is hosted by freshwater snails and can attach to watercress and other aquatic plants. Consuming raw, unwashed watercress with these parasites can lead to a serious infection.
• Small Pests and Bugs: As watercress grows in water, it can harbor small snails and other insects, which are easily removed with a thorough rinse.

A Comparison of Washing Methods

Choosing the right method for washing your watercress depends on whether you're dealing with cultivated or wild greens. A basic rinse is often sufficient for store-bought, but wild-harvested cress demands greater precautions.

Washing Method	Best For	Effectiveness	Special Considerations
Cold Water Rinse	Store-bought bunches or bags not labeled "triple-washed"	Removes most dirt, grit, and surface bacteria.	Simple and quick. Use a colander and rinse until water runs clear.
Bowl Soak and Swirl	Store-bought or wild watercress	Excellent for dislodging dirt and small pests trapped in leaves.	Requires soaking for a few minutes and multiple changes of water. A salad spinner is ideal for drying.
Hot Water Blanching	Wild-harvested watercress	Kills bacteria and parasites, including liver fluke.	Alters the texture and flavor, making it unsuitable for salads. The cress becomes wilted and is best used for soups.
Wild Foraging Precaution	Wild watercress from areas with livestock	The safest method for wild cress is cooking it thoroughly.	Necessary to kill the serious parasite risk of liver fluke. Avoid wild harvesting near grazing animals.

The Proper Technique for Washing Watercress

For store-bought watercress, a simple wash is usually enough. For wild watercress, extra steps are necessary. Here is a step-by-step guide:

1. Preparation: Fill a large bowl or clean sink with cold water.
2. Soak: Submerge the watercress and gently swish it around to loosen any dirt, grit, or debris.
3. Inspect: For wild watercress, carefully inspect the leaves and stems for any snails or visible pests.
4. Rinse: Remove the watercress and drain the dirty water. Rinse the bowl and repeat the process with fresh, cold water until the water remains clear.
5. Drain: Place the watercress in a colander and rinse one last time under cool, running water.
6. Dry: Dry the watercress thoroughly with a salad spinner or by gently patting it with paper towels. Excess moisture can cause the greens to wilt faster.

Risks of Not Washing

Skipping the wash, especially with wild watercress, carries significant health risks. While commercially grown watercress is generally safer due to regulated growing conditions, recalls prove that no process is foolproof. Wild watercress, however, presents a clear and serious danger, particularly if harvested near fields where livestock graze. The liver fluke parasite can lead to a condition called fascioliasis, which, if untreated, can cause severe organ damage. Symptoms can include fever, abdominal pain, nausea, and vomiting. Proper cleaning is a simple, effective measure to mitigate these risks and enjoy watercress safely.

Conclusion

In short, the question is not if watercress needs to be washed, but rather how thoroughly. All watercress should be washed, including pre-packaged versions, to remove surface-level dirt and contaminants. The method of washing depends heavily on the source. While a thorough rinse and soak is suitable for most store-bought varieties, wild watercress should always be cooked to eliminate the severe risk of liver fluke infection. By incorporating proper washing techniques into your food preparation routine, you can enjoy this peppery, nutritious superfood with confidence and peace of mind. For additional information on fresh produce safety, refer to guidelines from the Food and Drug Administration (FDA).

Note: For those foraging for wild watercress, a cautionary tale from a Reddit user serves as a memorable warning. The user, after washing a newly purchased bunch, was shocked to discover snails and insects floating in the water, underscoring the hidden contaminants that can exist on produce.

Storing Washed vs. Unwashed Watercress

How you plan to store watercress will also influence your washing strategy. Washed watercress has a shorter shelf life than unwashed. It's often best to wash watercress just before you intend to use it, unless you plan to store it using a specific method designed for moisture management.

• Storing Unwashed: Keep the watercress in its original, slightly perforated bag or a damp paper towel to maintain freshness. This can keep it fresh for several days, but it must be washed immediately before use.
• Storing Washed: After washing and drying thoroughly, you can store it in an airtight container lined with a paper towel. Another effective method is to treat it like flowers by placing the stems in a cup of water in the fridge, with the leaves covered by a plastic bag.

Frequently Asked Questions

Is pre-packaged watercress already washed?

While many pre-packaged brands are labeled "triple-washed" or "ready-to-eat," past outbreaks of foodborne illness suggest it is safest to wash all produce again at home, including watercress.

What happens if you don't wash wild watercress?

If you don't wash or cook wild watercress, you risk ingesting the liver fluke parasite (Fasciola hepatica), which can lead to a serious infection causing organ damage, abdominal pain, fever, and other severe symptoms.

What is the best way to wash watercress?

The most effective method is to submerge the watercress in a large bowl of cold water, swish it gently, and change the water several times until no dirt or grit remains. Then, rinse it under running water and dry it.

Can I eat the stems of watercress?

Yes, both the leaves and stems of watercress are edible and have a peppery taste. However, you may want to trim off any tough or oversized stems, especially from older bunches.

How do I dry watercress after washing it?

After rinsing, you can use a salad spinner to efficiently remove excess water. Alternatively, you can blot the watercress gently with paper towels.

How should I store washed watercress?

To store washed watercress, ensure it is thoroughly dry. Place it in an airtight container lined with a paper towel in the refrigerator. Use it within a few days for the best flavor and texture.

Can I eat watercress from a local stream?

No, unless you are certain the water source is free from contamination, particularly from livestock grazing nearby. The safest option for wild-harvested watercress is to cook it thoroughly to kill any parasites.