Some people say that you should never refrigerate tomatoes. Is this really true?
I've been told for so long, by so many people, not to refrigerate my tomatoes that I'm not sure if I've ever done anything other than leave them on my counter. But the question has made me think back on it, and to be honest, I can remember losing quite a few beautiful summer tomatoes over the years to rapid rot and decomposition, because they were sitting out in sweltering heat.
And I think this gets right to the core of the trouble with this rule: While refrigerators tend to operate within a narrow band of temperatures, usually in the 35-to-40°F (2-to-4°C) zone, the actual temperature of most rooms can range anywhere from about 60°F (16°C) to upwards of 100°F (38°C), particularly if it's an un-air-conditioned space at the height of summer. Right now, for example, I'm typing this while sitting in my sweltering apartment, and I'd guess—based on the amount of sweat soaking from my lower back into my chair—that it's at least 90°F (32°C) in here. Is 90° really better for a tomato than 37°F (3°C)? And if so, for how long?
To answer these questions, I set up a series of experiments that spanned an entire summer and included literally hundreds upon hundreds of tomatoes of different sources, varieties, and quality and ripeness levels, and recruited a small army of blind-tasters to evaluate the results. I even asked Kenji to run the same tests over in California, just to make sure my results were reproducible.
Before I get to my testing details, let me first explain my results and offer some recommendations, right up front. They’re controversial only because they buck what has become conventional and deep-rooted wisdom; but really, what I found makes a lot of sense.
Should You Refrigerate Tomatoes? Here’s the Short Answer
If Your Tomatoes Have Never Been Refrigerated (i.e., if you grew them yourself or bought them from a farmers market stand you trust, in season):
- Remove the stems and store unripe tomatoes upside down on a plate or cutting board at room temperature until they fully ripen. (Why upside down? Read Kenji’s article on why stem side down is best.)
- Consume fully ripened tomatoes immediately.
- Refrigerate any unconsumed fully ripe tomatoes, but allow them to come to room temperature before serving them. (To speed up this process, slice them while still cold—slices will warm up much more quickly than an intact fruit.) One study we've read suggests that refrigerating for no longer than three days is optimal.*
If Your Tomatoes Have Been Refrigerated (i.e., if you got them anywhere other than your backyard or the farmers market, in season):
- Leave them at room temperature until fully ripe, then store them in the refrigerator until ready to use.
*If you are inclined to read the full study, you can do so here. But this is the relevant quote: "Red ripe fruits were stored at 5°C for 1, 3, or 7 d followed by a recovery period of either 1 or 3 d at 20°C, and volatiles were measured. Compared with the day of harvest (day 0), no significant loss of flavor volatile content was observed after 1 or 3 d of cold storage."
It's as simple as that. Now, here's the (brief, for now) explanation.
The Reasons Behind Different Storage Methods
A refrigerator is cold—colder than is ideal for tomatoes. This is a basic fact, and it’s the fact upon which the "never refrigerate a tomato" rule is based. But that rule fails to acknowledge several real-world conditions that can complicate things. It also fails to recognize that not all tomatoes are affected by refrigeration equally.
So here’s what you need to know: Leave your tomatoes at room temp for as long as possible, especially if they’re still a little shy of hitting their peak ripeness. Once they hit their apex, though, you need to either eat them right away or refrigerate them. The refrigerator can buy you some time before the tomatoes begin to break down and eventually rot—something that can happen several hours after the tomato has peaked. And a refrigerated ripe tomato holds up and tastes better than one that has been left out at room temperature beyond its prime, especially if you allow the refrigerated one to return to room temperature before eating it.
And here’s the other thing to know: The refrigerator is not great for tomatoes—it can degrade their texture and dampen their flavor—but it’s far more harmful to lower-quality and underripe tomatoes than it is to truly ripe, delicious ones. Top-quality, in-season, picked-straight-from-the-vine ripe tomatoes do much better in the fridge than most conventional tomatoes from large industrial operations.
Test 1: Conventional Tomatoes
To run my first tomato experiment, I went out and bought three different varieties of tomato: first, run-of-the-mill hothouse tomatoes—you know, the kind that typically get sliced and served on cheap deli sandwiches; plum tomatoes; and, finally, some cherry tomatoes that came in a plastic clamshell and tried to look fancy by just barely holding on to their desiccated vine. (Nothing says farm-fresh like a withered, dried-out stem.)
I bought several of each variety, selecting similar-looking specimens to minimize variations in ripeness—fairly easy, given that these were all pretty crappy yet highly invariable mass-market fruit. In terms of relative quality, the cherry tomatoes were the best, the plums in the middle, and the standard ones were the worst.
I took them back to my mother’s place, where the central air is set to about 75 to 80°F (24 to 27°C). I put half of each kind in the fridge and the other half out on the counter.
After 1 Day of Storage
After letting the tomatoes sit in their respective environments for a day, I sat my mom and sister down and asked them to taste and rate my tomato samples, which I served to them blind. To make sure the cold of the refrigerator didn't sway their votes, I let the chilled tomatoes warm up to room temp before proceeding with the tasting.
Even before cutting into the tomatoes, I could see some differences. The standard tomatoes, pictured above, had turned redder on the counter than they had in the fridge, though the difference was subtle. Note the yellow flecks on the skin of the refrigerator tomato on the right, compared with the redder skin of the countertop tomato on the left.
The plum tomatoes pictured above showed a similar effect, with the countertop ones (at left in the photo above) redder than the chilled ones to the right. The whole cherry tomatoes, meanwhile, were harder to tell apart by sight.
Once I cut into them, a similar pattern emerged:
Inside, the standard tomato looked slightly more yellow and pale in the refrigerated sample than the countertop one, though both looked mealy and not particularly ripe.
The plum tomato showed the most drastic visual difference, with the refrigerated sample appearing more white and grainy in its flesh than the countertop one.
Here's an even closer look at the plum tomato, again with the refrigerated sample to the left.
The cherry tomatoes showed the least difference, with a just barely perceptible increase in redness in the countertop sample (at left).
As for the taste-test results? Well, first, my mom was disqualified because she kept rejecting all the tomatoes, regardless of storage method, while reminiscing about what they used to taste like in the farmlands of Maryland where she grew up in the '40s and '50s.
My sister, thankfully, was able to focus on the task at hand—analyzing the relative, not absolute, merits of these tomatoes—and give me her opinion. In each case, the tomato she picked as her favorite was the countertop sample: Not once did the refrigerator sample come out on top. She found the countertop ones to be more aromatic and sweet, with a better texture, than the refrigerated ones, though she said the differences weren't as apparent with the cherry tomatoes.
My own tasting of the samples backed her choices up, and she and I walked away with a few observations:
- First, a truly mediocre tomato, like the standard ones here, cannot be turned into a good tomato, no matter how you store it.
- A tomato that is just fine, but not great, like the plums I bought, can benefit quite a bit from being left out at room temp.
- Better-tasting tomatoes, like the cherries in this test, aren't as adversely affected by cold temperatures.
- Another detail that my sister pointed out: Tomatoes with more flesh and less seed jelly, like the standard ones here, are more likely to suffer textural degradation than varieties with very little flesh and more seed jelly, like the cherries.
So far, my test results were as I'd expected.
The Unexpected Turn After 2 Days of Storage
It was at this point that I thought I'd repeat my tasting after another day, confirm all my findings, and be done with it. So, a day later, I sat my family down again—this time my sister, stepfather, and mother (who, I explained to her, could only participate if she forgot about those mythic Maryland tomatoes and focused on the ones in front of her).
Once again, I let the refrigerated tomatoes warm up to room temperature before serving them alongside the countertop ones. But this time, I also stuck some of my countertop ones in the fridge a couple hours earlier, to compare briefly chilled countertop ones to room-temp multi-day-refrigerated ones. I served all the tomato samples blind.
And the weirdest thing happened: My sister reversed all her picks from the day before, and consistently selected the refrigerated tomatoes as her favorites this time. What?
Confused, I sat down at the table and asked my sister to serve me the samples blind. Here's what's even more weird: Because I had been slicing, smelling, and tasting the tomatoes as I served them, I was able to correctly differentiate the refrigerated and countertop samples every time by smell alone. But even though I could tell them apart, I had to agree with my sister—the refrigerated ones were better that day, in all cases.
So, in the case of these three types of conventional supermarket tomatoes, the refrigerator initially made them worse, but with extra time the refrigerated ones became better than the countertop ones.
What Gives?
One possibility with this initial set of test results is that, because my mom's home was a warmish 75 to 80°F (24 to 27°C), the heat started to take its toll on my countertop samples once enough time had elapsed.
As I've reviewed some tomato literature, this explanation starts to make some sense, though I haven't verified that it's correct. What most studies have found is that storage temperatures can affect both a tomato's texture and its volatile aromatics (which are responsible for its complex scent), with colder temperatures degrading the volatiles more quickly.
According to this fact sheet from the Department of Plant Sciences at UC Davis, firm, ripe tomatoes are best held at anywhere from 44 to 50°F (7 to 10°C), which is higher than fridge temperature but lower than most rooms. (The report says to store less ripe tomatoes at higher temperatures, which supports my above observation that riper tomatoes can withstand the cold, while less ripe ones benefit from some warmth.) This French study, meanwhile, found that 4°C (39°F) temperatures are much more harmful to volatiles in the tomato than 20°C (68°F), though it also found that letting refrigerated tomatoes sit out for 24 hours at 68°F reversed some of the ill effects.
But what the studies I've found fail to explore is the effect of even higher temperatures on tomato storage. That may not be a problem for tomato and produce companies with refrigerated trucks and warehouses, but it is a problem for those of us at home, since not all of us with air conditioning have the thermostat set as low as 68°F, or even have it running 24/7; some of us, like me, don't have air conditioning at all. Given that tomatoes ripen in the summer, the challenge is that we're trying to store them at home during a season characterized by intense heat, and we don't usually have storage conditions in the 44-to-50°F range.
This article from Business Insider illustrates my point well: The scientist quoted in the piece, who is recommending that we not refrigerate our tomatoes, casually defines normal kitchen temperature as between 68 and 73°F (20 and 23°C). That is a chilly kitchen—colder than most kitchens I’ve visited in the summertime! Unless you're blasting your AC 24/7 from July through September, it's probably colder than your kitchen, too.
Test 2: In-Season, Local Tomatoes
My first test delivered some surprises, but it was based on just a few varieties of lesser-quality supermarket tomatoes, which left some questions unanswered. Specifically: How does this wisdom apply to really good, farm-fresh tomatoes that are perfectly ripe and ready to eat, and are there any more useful guidelines for storing tomatoes?
To find out, I spent the next several weeks loading up on all kinds of fantastic tomatoes. Every time I went to the farmers market, I'd buy as many tomatoes as I could carry, then leave half on the counter and half in the fridge for at least a day before tasting them.
You'd think that there'd be many studies out there that look at the effects of storage on really great, ripe-picked tomatoes that have come straight from the farm, but as it turns out, most of the research money out there goes toward studying the effects of storage on the average, picked-when-still-green supermarket tomato. My tests would try to fill in the gaps.
In all, I ran 11 different rounds of tests, each of which included several types of tomato, from hybrids like beefsteaks to many different heirloom varieties in all shapes and sizes. In all cases, the tomatoes were bought fully ripe from the farmers market. I kept half the tomatoes on the counter and half in the fridge. I conducted eight of the tastings after a roughly 24-hour storage period, and the remaining four tastings after two or more days of storage (with no tastings after longer than four days of storage). Like tomatoes were always compared with like (so, no pitting a beefsteak against a cherry tomato), and all refrigerated tomatoes were allowed to come to room temperature before serving, to eliminate temperature bias. When other tasters were present, which was true the majority of the time, everyone but the server tasted blind.
Here are the basic results:
- In one out of 11 tests, tasters unanimously chose the countertop tomatoes over the refrigerated ones. This was one of the batches stored for 24 hours.
- In five out of 11 tests, tasters unanimously preferred the refrigerated tomatoes—the countertop tomatoes tasted flat and dull in comparison.
- The remaining five tests yielded either split votes or an inability to differentiate between the two samples. In all instances where the votes were split, no tasters had strong convictions about which tomato was better, so I'm considering all five of these cases in which the refrigerator and the countertop tomatoes were essentially indistinguishable from each other.
These results jibe with my original theory: Because peak-season farmers market tomatoes are already perfectly ripe, they benefit very little from extra time in the heat, and in many cases they are harmed by it, while the refrigerator does minimal harm once tomatoes are ripe. Even the texture of the ripe tomatoes was not noticeably affected by the refrigerator.
Let me leave you with one lasting image that, all on its own, should illustrate my point. Below, you can see the relative merits of counter versus refrigerator storage at the four-day mark on a pair of tomatoes that started out just about equally ripe. The countertop tomato is degrading more quickly due to its high-heat environment.
Great, you might be thinking. You just showed that tomatoes rot faster at room temperature than in the refrigerator. Big whoop... But that’s exactly the point: If you're buying your tomatoes ripe (which we should all be doing!) and need to store them for an extra day or two, you're often better off storing them in the fridge than on the countertop.
Where Do We Stand Now?
The question of whether to refrigerate tomatoes or not is really a question of which is the lesser of two evils. I have little doubt that food scientists are right, and that the ideal storage temperature for tomatoes is somewhere between 55 and 70°F (13 and 21°C)—at least for supermarket tomatoes. But I also know that few of us maintain such consistently cool temperatures at home. If you have a chilly cellar or a wine fridge, then count yourself lucky. If your thermostat is always set that low, then I don't want to see your electric bill. The rest of us have a choice: warm (or even sweltering) counter, or too-cold fridge. Once your tomatoes are ripe, the fridge is usually your best bet.
Based on my tests, here are some more fully fleshed-out tomato-storage guidelines:
- If at all possible, buy only as many perfectly ripe tomatoes as you can eat within a day or two, keep them stored stem side down on a flat surface at room temperature, and make sure to eat them all within the first day or two.
- If you buy underripe tomatoes, leave them out at room temperature until they're fully ripened, then move them to a cooler spot for longer storage.
- If you have a wine fridge or cool cellar, store all ripe tomatoes that you can't eat within the first day there.
- If you don't have a wine fridge or cool cellar, store all ripe tomatoes that you can't eat within the first day in the refrigerator.
- If you're storing tomatoes in the refrigerator, it may be better to locate them on a top shelf near the door, which is often warmer than the bottom and back of the fridge.
- If you're the kind of person who can't stand eating fridge-cold tomatoes and doesn't have the time or patience to let them warm back up on the counter, then you've got some tough decisions ahead of you, I'm afraid.
Test 3: In Search of More Data
My tomato tests were challenging the long-held idea that a tomato should never see the inside of a refrigerator, but I still needed more data.
After all, more data is always a good thing, and reproducibility is the foundation of any reliable experimental result. I decided to run more tests, and asked Kenji to run some over on the West Coast, just to see if he would get similar results as mine. Either my initial observations would hold, or I'd have to revise them.
Kenji and I split up the tasks. Here on the East Coast, I went to the farmers market and bought a large load of both regular red tomatoes and a variety of heirlooms.** My plan was to do one giant blind tasting in the office, with as many people as I could wrangle, and more quantitative measures (as opposed to the strictly qualitative assessments I had done earlier in the summer). Then I'd follow that with some triangle tests to see just how well tasters could really differentiate between refrigerated and room-temp samples.
** For those wondering if I had bought crappy tomatoes from a wholesaler at the market, it's worth pointing out that NYC Greenmarket allows vendors to sell only produce they've grown themselves, and that I had talked to the farmers to confirm the tomatoes had not been previously refrigerated.
Meanwhile, over yonder in the Bay Area, Kenji went and picked his own tomatoes straight from the vine, just to remove any lingering question about the handling practices of the middlemen. He then did his own blind tastings with those tomatoes. He also examined the refrigerated tomatoes for signs of mealiness.
So, what were our results? Shocker! The refrigerator still isn’t as evil as the never-refrigerate rule makes it seem.
My East Coast Tests
When I ran my initial series of tests, it was at the height of summer in New York City, with temperatures well above 80°F (27°C). Without air conditioning in my apartment, I found that more often than not, refrigerated ripe tomatoes tasted better than ones that continued to sit out on the counter, suggesting that in instances in which room temperature was above roughly 80°F, refrigeration was often preferable.***
*** Remember, I had found several scientific studies that compared refrigeration to "room-temperature" conditions, in which the room-temp conditions were all below 70°F (21°C), colder than many summertime rooms in real life; I hadn't found a single study that compared refrigeration to warmer storage conditions. I also found no studies that examined truly ripe tomatoes—they seemed to have all been designed with the concerns of large-scale tomato growers, who pick their tomatoes while still green, in mind, and not the concerns of those of us at home.
But when I went out to run this latest round of tests, temperatures in New York had fallen considerably, down to the 60s and 70s. My whole argument revolved around very hot summertime conditions, and I had made no claim that the refrigerator was equal to or better than temps in the 70s and below. With conditions shifting, I wasn’t sure what I’d see this time.
The Blind Tasting
As I mentioned above, I bought a variety of tomatoes at the farmers market. Most of them were regular red slicing tomatoes; the rest were an assortment of heirlooms. Their quality was variable. I put half of each type of tomato in the refrigerator and the other half out on the counter. The next day, I took the refrigerated ones out and let them come back up to room temperature.
I then cut up each tomato and assigned it a number. I had 10 tasters work their way through the samples, each in a different order, to ensure that no single tomato was disadvantaged due to tasters' palate fatigue. Tasters evaluated the tomatoes on a scale of one to 10 on four criteria: overall preference, flavor, aroma, and texture. The overall-preference score aligned almost exactly with the other scores, so the below chart shows the overall-preference score, since the others look pretty much the same:
Before going into the specifics, I want to reiterate that this test compared tomatoes stored at temperatures in the low 70s to refrigerated ones, essentially pitting refrigerated tomatoes against much more ideal conditions than in my previous tests.
Instead of seeing a clear and decisive difference between refrigerated tomatoes and counter tomatoes, the differences were very small. On average, the counter tomatoes just barely edged out the refrigerated ones, except with the small yellow heirloom tomatoes, in which case the refrigerated ones received the highest average score. That was also the highest average score of all the tomatoes, which means that even when compared with much more ideal conditions, refrigerated tomatoes are capable of coming out on top: absolutely not what we'd expect if refrigeration were really as bad as the common wisdom claims.
Of all the tomatoes in the tasting, all of us (the 10 tasters plus me) agreed, unanimously, that the small yellow tomatoes—the ones that scored highest in the fridge and out—were the best.
Meanwhile, the basic red tomatoes were the worst in terms of overall quality, and they also were the set in which the refrigerated tomatoes scored the lowest. This lends further support to my theory that the higher-quality and riper the tomato, the less harm the refrigerator will do to it.
Simply put, really good, ripe tomatoes tend to do well in the refrigerator, while lower-quality tomatoes remain bad or get worse in the fridge: Underripe tomatoes continue to be underripe, and mealy tomatoes become mealier.
One more very important detail: What the chart above shows are average scores. But within each group, there was a notable variance. For the red tomatoes, for instance, I had individual refrigerated samples that scored as high as 5.5, and countertop tomatoes that scored as low as 3.6. So while the countertop tomatoes slightly edged out the refrigerated ones when averaged together, the distribution of individual tomato scores was much less consistent, regardless of storage method. This, too, suggests that the fruit itself is the bigger factor in how it will handle storage conditions, not some blanket rule about the storage conditions themselves.
The Triangle Tests
Next up, the triangle test, which determines whether blind-tasters can pick the odd sample out through many rounds of tasting. I wasn't totally convinced there was an advantage to this test: I had never claimed that refrigerated tomatoes were going to always be indistinguishable from room-temp ones. In my earlier tests, we were unable to differentiate between refrigerated and unrefrigerated about half the time. But in the other instances, the differences were apparent; it's just that in those cases, we tended to like the refrigerated ones more.
Still, I figured there was no harm in trying a triangle test out. I did a test run on Max one night, using more of those not-so-great red tomatoes that I had set aside. Max has a very good palate, so I was curious to see how he would do. In each tasting round, I presented Max with three slices of tomato in random order (either two refrigerated and one countertop, or two countertop and one refrigerated), and his task was to see if he could figure out which of the three was the odd one out. After 12 rounds, Max had correctly identified the odd tomato six times, which is slightly better than chance. (In a triangle test, random guessing should yield correct answers one-third of the time, which in this case would be four out of the 12 rounds.) When he was able to correctly identify the tomato samples, he also picked the counter sample(s) as his preference.
But when he got it wrong, he sometimes picked refrigerated slices as his preference. This is consistent with the blind-tasting results above: Even though the red counter tomatoes edged out the refrigerated ones overall, there were individual refrigerated samples within the mix that scored higher than some of the counter samples.
But 12 rounds isn't enough, so the next day I bought even more tomatoes, refrigerated half overnight, and then lined up five different tasters for a new session of triangle testing, with 24 rounds total. Out of 24 rounds, we'd expect random guessing to be correct eight times (one-third of the total number of rounds). By the end of my session, my tasters had been correct nine out of 24 times, performing just a hair above the random-guessing rate.
I'll be honest: As I was slicing the tomatoes for these tests, I felt that the differences were more apparent, but then again, I knew which was which. (In some cases, I thought the counter tomatoes were better; in others, I thought the refrigerated ones were.) What this test shows is that once that knowledge is removed, the differences can be subtle enough that tasters have a very hard time telling refrigerated and countertop tomatoes apart. So, while I don't believe that room-temp and refrigerated tomatoes are totally indistinguishable, these tests indicate that the claims of horrible effects of refrigeration on ripe tomatoes are exaggerated.
Kenji's Tests
Out in the Bay Area, Kenji also ran his tests, with tomatoes he picked directly off the vine himself. Just as with my most recent tests, Kenji's house is in the low 70s and mid-to-high 60s—theoretically ideal tomato-storage conditions. I'm going to let Kenji tell you in his own words:
"The tomatoes that I picked were fully ripe. I held them for two days, half in the fridge, half on the counter. I let the refrigerated tomatoes come back to room temp before tasting, then I did a blind taste test with six people. Of those six, two did simple side-by-side preference tests: They both picked the fridge tomatoes as superior. The other four did triangle tests: Of those, three correctly picked the odd tomato out, and all picked the refrigerated tomatoes as superior. The fourth person who did the triangle test selected the odd one out incorrectly, but she still picked the refrigerated tomato as her favorite.
"I also did a test slicing tomatoes open and checking them (subjectively) for mealiness as they warmed up. I didn't notice any mealiness from a fully ripe tomato that had been put in the refrigerator."
Kenji's results support what I suggested above: Refrigerated and countertop tomatoes won't always be indistinguishable, but even when they are, the refrigerator isn't by any means guaranteed to be worse.
Our results from these latest tests are, frankly, as surprising to me as I imagine they are to many of you reading this: Before these tests, I never, ever would have argued that tomatoes kept at a mild 70°F could be beaten by or mistaken for refrigerated tomatoes.
Yet here we have multiple tests, performed on two different coasts by two different people, with many different varieties of tomato, and that's exactly what we're seeing.
On the Value of Science and the Danger of Misusing It
Throughout this tomato-tasting experience, I've reflected quite a bit on the role of science in all of this.
Science itself has done nothing wrong: It's a beautiful system—the best one we've got—for answering questions about how pretty much everything in the observable universe works. But it's easy for us to misuse it, and I think it's just such a misuse that created this inflexible rule about tomato storage in the first place. If you'll bear with me, I'll explain:
As I've written above, all of the academic studies I found on tomato storage were based on a narrow set of conditions: namely, tomatoes picked when underripe, and stored in temperatures below 70°F. Those studies concluded—and I'm willing to believe that they're correct—that those tomatoes are harmed by refrigeration and are better stored at slightly higher temperatures, in the 50s and 60s. The studies I found didn't examine tomatoes that were picked when fully ripe, and they didn't consider warmer storage temperatures, certainly not above 80°F.
So what happens with these studies? This is just a scenario I've made up, but it's plausible to me, and it shows how the further we get from the original data, the more likely it is that the data will be misinterpreted: The big-ag tomato growers follow the research and begin storing their underripe tomatoes in cool temperatures (but not as cold as a refrigerator), and wholesalers do the same. Word gets to the produce vendor: Don't refrigerate these tomatoes, it's bad for them. Then the produce vendor tells the customer: Don't refrigerate your tomatoes, it's bad for them.
But that last step is the problem: The don't-refrigerate wisdom was good throughout the supply chain and kept the tomatoes in the best possible condition, but it doesn't necessarily apply to the retail customer with different storage conditions at home, or to tomatoes that are picked when ripe—conditions that had not been tested in any scientific study I found.
Another example of the misuse of science is in this Alton Brown Facebook directive: "Do me a favor: Never put tomatoes in the refrigerator," he implores. "If they drop below 50 degrees F, a flavor compound called (Z)-3-hexenal is just going to flip itself off like a chemical switch ... permanently." Uh-oh, (Z)-3-hexenal gets switched off permanently? That sounds really bad.
Let’s assume this thing about (Z)-3-hexenal is true. My question is: So what? In a complex biological structure like a tomato, am I supposed to believe that because one single aroma molecule goes dormant, that's therefore a good enough reason to never refrigerate a tomato? What about all the thousands and thousands of other complex processes that are taking place in a tomato as it ages? How can we possibly draw an actionable conclusion from one single factor in such an intricate system as a tomato?
This is a problem in a lot of science-based journalism: Scientists perform a study and publish their results. Lay publications, looking to make that information relevant to the lay person, try to find some kind of practical advice buried in the findings. Scientists have found that vitamins are important to the human body? Take them as a pill! Scientists have found that fat is bad? Stop eating fat! Scientists have found that fat isn't as bad as they thought? Stop eating carbs!
The problem isn't necessarily with the scientists; it's with the people trying to give concrete advice about how to live and act based on the work of the scientists. It puts us in hot water far too often.
Tomato Storage: Conclusion
None of my tests, nor Kenji's, are rigorous enough for publication in any kind of scientific journal, but I think we've each had clear enough results that no one should at this point continue to believe that the no-refrigeration rule is always true. At the very least, the rule exaggerates the harm that a refrigerator does to ripe tomatoes, while not considering the sometimes greater harm that can befall that same tomato if left at room temperature—especially the warmer that room gets.
As for me, next time tomato season rolls around, I'll stick them in the fridge when it seems like they're ripe enough.**** And I won't feel a smidgen of shame about it.
**** While I’m at it, I’ll also be storing them in the fridge upside down, for reasons Kenji explains here.
Editor’s Note: This content was originally published as a three-part series. It has since been condensed into a single article.