Should you wash berries before storing them?

I’m sure this has happened to you at least once in your life. You buy some delicious looking berries and the next day they’re covered in mold!

Produce usually goes bad for one of two reasons. Either it continues to ripen until it’s rotten, or it simply molds.

Berries, specifically blueberries, blackberries, cherries, grapes, raspberries, and strawberries, are non-climacteric and non-ripening.

This means that they don’t produce a lot of ethylene (a ripening hormone) and they don’t continue to ripen once they’ve been pulled off the plant.

So usually when they go bad, it’s because they’ve molded.

There are two schools of thought when it comes to dealing with this.

One idea is that berries should be kept cool in the fridge and not washed until just before eating. Washing the berries may cause them to mold much quicker due to the extra moisture.

The second idea is that washing your berries in a vinegar solution or hot water bath will kill the mold spores and bacteria that would otherwise cause them to rot, leaving the berries clean and fresh.

Time to experiment!

(hint - you can scroll the end to skip to the results)

Blackberries and raspberries happened to be on sale recently so I picked up a pint of each to test the idea that washed berries would mold faster than unwashed ones. I purchased, prepped, and stored these berries on May 15th.

I separated the pint into two groups, one that would be washed in a vinegar solution and one that would be stored unwashed in the fridge.

I eyeballed my vinegar solution so it was close to 1 part vinegar to 5 parts water. I let the berries hang out in the vinegar solution for a minute, then drained and rinsed them.

A good rinse will remove any lingering vinegar on the berries.

If you’re sensitive to the smell or taste of vinegar you can try salt water or scalding water instead. I haven’t personally tried either of those methods, but salt water is common for washing lettuce and scalding water was recommended by someone who’s had success with that method.

I turned the washed raspberries upside down on a paper towel so that water could drain out, then gently patted dry the outside. The washed blackberries were also patted dry.

I placed a paper towel on the bottom of the container for the berries that had been washed. Then into the fridge they went!

11 days later!!

I have to say, this experiment was like waiting for a pot of water to boil. I checked the berries every two days waiting for something to happen. And it didn't. That's right, nothing happened!

Honestly, by the time Memorial Day came around and they all looked fine, I wasn't sure what I was going to say in this post. (I do have some lessons learned, so scroll to the end or keep reading).

The berries on the left went straight from the store into the plastic container. The berries on the right, with the paper towel, were washed in a vinegar/water solution.

The berries that had been washed were slightly softer than the berries that had been left plain. The texture wasn't significantly different. It was only something I noticed while eating them. Both batches tasted the same.

The berries on the left were plain and the ones on the right, with the paper towel, were washed in a vinegar/water solution.

I didn't noticed any difference between the washed and unwashed blackberries. Both batches were much more tart than an average blackberry, though their structure was fine. I think their extra tartness would have made for a lovely pie.

I'll run this experiment again in the future. I was not expecting these results at all! I honestly didn't know which batch would last the longest but I was certain there would be a clear winner either way.

The biggest surprise to me was that the washed raspberries kept so well and that they still had great flavor. I've read in many places that raspberries are the one berry that really shouldn't be washed ahead of time, because they're so delicate.

After considering the results for a couple of days (I ended the experiment and took photos last Tuesday, May 26th) I think the berries may have lasted so long due to the fact that they weren't crowded together.

Often times, when I find a package of berries at the store that has molded, it's the berries on the bottom, squished between others, that have molded first. Allowing for a little extra space may be the key to keeping berries fresher, longer.

The Take-Away

  • Dry your berries thoroughly after washing them.

  • Keep a paper towel in the container to prevent condensation build up from dripping on the berries.

  • Use a separate container large enough to store the berries in one layer with room to breathe.

  • Keep your berries in the middle of the fridge, towards the back. This is where your fridge is coldest.

  • Berries are meant to be eaten! If your berries last for 11 days it's time to pull out the yogurt and make a snack!