Why You Still Need to Wash Pre-Washed Salad
If you buy a pre-washed ready to eat bag of salad leaves, do you tip straight out onto a plate – or do you thoroughly wash it first? The whole idea of bagged salad mixes is convenience, so it’s no surprise most people don’t wash.
But how do they wash the salad before they bag it? Well it turns out diluted chlorine is commonly used. The chlorine is used to kill any harmful bacteria to ensure the lettuce is safe for our consumption. Seemingly even organic produce is allowed to use a weak chlorine solution for this purpose. Whilst there is supposed to be no trace of the chlorine 24 hours after treatment, do you trust your salad to be chemical free?
With outbreaks of e-coli and salmonella, it’s not surprising the salad growers are keen to sanitise their product. With salad available all year round the pressure is on to produce a cheap product – often meaning growers don’t provide sanitary conditions for their workers – hence the contamination risk. Unfortunately sanitising salad doesn’t remove the risk of contamination, it just makes it less likely.
So what’s the answer? If pre-washed salad could still be contaminated and could contain traces of chlorine is it worth paying the price premium?
Wash your own
A far better option is to spend a fraction of the cost buying fresh, unpackaged greens. Get rid of any wilted, torn or bruised leaves and let them sit in a sink full of ice cold water for 20 minutes. Use a salad spinner to get rid of the water and roll in paper towels to get the rest of the water out. If you store in plastic bags with paper towels to absorb any remaining water, they should remain fresh for over a week in the fridge.
If you buy a pre-washed ready to eat bag of salad leaves, do you tip straight out onto a plate – or do you thoroughly wash it first? The whole idea of bagged salad mixes is convenience, so it’s no surprise most people don’t wash.
But how do they wash the salad before they bag it? Well it turns out diluted chlorine is commonly used. The chlorine is used to kill any harmful bacteria to ensure the lettuce is safe for our consumption. Seemingly even organic produce is allowed to use a weak chlorine solution for this purpose. Whilst there is supposed to be no trace of the chlorine 24 hours after treatment, do you trust your salad to be chemical free?
With outbreaks of e-coli and salmonella, it’s not surprising the salad growers are keen to sanitise their product. With salad available all year round the pressure is on to produce a cheap product – often meaning growers don’t provide sanitary conditions for their workers – hence the contamination risk. Unfortunately sanitising salad doesn’t remove the risk of contamination, it just makes it less likely.
So what’s the answer? If pre-washed salad could still be contaminated and could contain traces of chlorine is it worth paying the price premium?
Wash your own
A far better option is to spend a fraction of the cost buying fresh, unpackaged greens. Get rid of any wilted, torn or bruised leaves and let them sit in a sink full of ice cold water for 20 minutes. Use a salad spinner to get rid of the water and roll in paper towels to get the rest of the water out. If you store in plastic bags with paper towels to absorb any remaining water, they should remain fresh for over a week in the fridge.
How Safe Is Bagged Salad Really?
Despite the chlorine treatment and promises of hygiene, studies have shown that bagged salad is one of the most common culprits when it comes to foodborne illness outbreaks. The moist environment inside the bag, combined with time spent on supermarket shelves, provides the perfect breeding ground for harmful bacteria.
Even a small nick or tear in a leaf can act as an entry point for pathogens like listeria or salmonella. Once inside, bacteria are very difficult to remove—even with washing. If you absolutely must use a bagged salad, inspect the bag closely. Avoid any with condensation, damaged leaves, or with a strong odour upon opening.
Choose Seasonal and Local When You Can
One of the benefits of shopping at your local farmer’s market or even growing your own salad greens is the increased control you have over how the produce was grown and handled. Greens harvested locally are more likely to be fresher and grown in smaller-scale operations with better hygiene standards. Seasonal greens are also less likely to be forced to grow under unnatural conditions or heavily sprayed with chemicals.
When you buy direct from a grower, you can ask how the produce was washed and stored. Many small growers use fresh water only or non-chemical alternatives such as vinegar washes or UV treatments to remove dirt and reduce bacteria.
DIY Salad Mix: The Healthier Option
Why not build your own salad mix at home? Try a combination of baby spinach, rocket (arugula), cos (romaine), and fresh herbs like parsley or coriander. Wash thoroughly, dry, and store in glass containers lined with cloth or paper towel. This gives you all the convenience of a grab-and-go salad without the risk.
To make it even easier, prep several small containers or jars with a base of greens and a few toppings like shredded carrot, chopped cucumber, or nuts. Then just add dressing when you’re ready to eat. It takes just a few extra minutes to do, and you control every ingredient.
Understanding the Chlorine Residue Risk
Though industry groups insist the chlorine used in salad washing is safe and evaporates before reaching consumers, some research suggests chlorine by-products may still be present. Chlorinated compounds can potentially react with organic matter to form substances like trihalomethanes, which have raised health concerns in large quantities.
While occasional exposure is unlikely to cause harm, regular consumption of heavily processed or treated produce may contribute to long-term chemical exposure. Washing your produce at home with a mild vinegar solution (1 part white vinegar to 3 parts water) followed by a cold rinse is a simple step you can take to remove surface residues without adding more chemicals.
The Paleo Take on Convenience
From a Paleo perspective, eating whole, unprocessed, and locally sourced food is always the priority. Bagged salad might offer a quick fix, but it’s a long way from how our ancestors would have gathered and eaten greens. Investing time into washing and preparing your food is part of reconnecting with the process of eating well. It’s also more budget-friendly and significantly reduces your plastic consumption.
Final Thoughts
Next time you're tempted to toss a bag of salad into your trolley, think twice. A little preparation goes a long way toward ensuring your leafy greens are as clean, chemical-free, and nutrient-rich as possible. Washing your own greens might take a few extra minutes, but the peace of mind—and potential health benefits—are worth it.
How to you wash yours?
