The bounty of summer is upon us and it is time to investigate that most wonderful invention, the refrigerator. Winter harvests produce tough, solid produce, but the joy of summer is in tender, exquisite, gentle fruit and vegetables. These things can spoil quickly and our attempts to keep them in our homes are often met with mealy frustration. But what causes fruit to become mealy? Can it be avoided?
The short answer is: YES. Temperature is both our friend and our enemy as we preserve our favorite flavors from the summer. Fruits and veggies all ripen at different paces and require different temperatures to maintain both their structure and flavor.
Of course, it is helpful to understand what mealy means from a chemical standpoint. When fruit enters the ripening process it produces a series of enzymes that help break down undesirable qualities. Chloroplast is broken down to reveal reds and yellows and oranges instead of just green. Pectinase helps soften the glue that holds cell walls together, thus releasing juices. And most importantly, starch is converted to sugar. When fruit is picked, lowered to 50 degrees before it has ripened, then brought back to room temperature, these enzymes do not act properly. The pectin is either not disrupted at all or entirely dissolved. And the starch never quite makes the transition to sugar. What are we left with? Mealy fruit, or floury fruit. Which is to say, fruit that has a high starch content and dissolved cell walls. The juices are not released, they are absorbed and stuck in cells. The fruit is not sweet, nor is it supple. It is dry and cottony.
First up we have the hero of the summer, peaches. This is, perhaps, the number one fruit we keep in mind when we think of mealy ruination. Peaches, which are soft fleshed stone fruit, are particularly susceptible to temperature fluctuations. Now, this can as easily be the fault of your produce buyer as it can be laid on your shoulders. Peaches can ripen off the branch, so they are picked when they’re still hard and slightly green, then transported at close to 36 degrees. This temperature “pauses” the ripening process, which can restart once the fruit arrives at your grocer.
However, if the peaches are placed in refrigeration between 37 and 50 degrees before they have reached full ripeness then the maturation process is stopped and we end up with something flavorless, without aroma, and of a disgraced texture. They can also become mealy if placed in near freezing temperatures after becoming fully ripened. So, to avoid a terrible experience here you must allow the fruit to fully ripen on your counter before refrigerating it. And even then, beware of too-frigid an environment. Keep your peaches in a produce drawer, certainly not on the top shelf nor next to the wall shared with your freezer.
Perhaps the number one fruit to inspire debate in the kitchen, the tomato is another piece of produce you want to keep away from extreme temperatures. Food scientists all over suggest that tomatoes should never be kept in the fridge. Colder temperatures inhibit the chemicals that lead to a ripe tomato flavor and aroma (similar to peaches). However, the research is limited and blind taste tests often are inconclusive. From my own personal experience I treat tomatoes like peaches and allow them to ripen at room temperature and then keep them in the fridge. However, unlike peaches, I let the tomatoes come to room temperature again before eating. A cold tomato is devoid of personality in my book.
Melons are tricksters, there is not a universal rule for their ripening. We must look at them in two camps: those that can continue to ripen off the vine and those that will never change once harvested. A simple rule to determine which is which: those with netted skins and rinds (canteloupe, galia, sharlyn) will continue to ripen and should not be refrigerated until they reach their pinnacle. Those with smooth skin (honeydew, canary, watermelon) will not ripen much more once picked. Chill them or not, it won’t make much difference. When buying smooth skinned melons make sure they are fully ripe!
Cucumbers, eggplant, and peppers all are tropical fruits (they all have internal seeds). Refrigeration is fine for a few days, but try not to let them linger in your crisper. They aren’t going to ripen any more and they are susceptible to pitting and withering.
Basil is curious for its aversion to cold. Most herbs are fine when stored with a damp paper towel in your fridge, but basil will blacken quickly. Keep this herb at room temperature and use immediately.
Remember: the shorter the distance from tree to table the better chance you have of avoiding mealy fruit. When produce is transferred from farmer to distributor to truck to truck to grocery store it will have passed through a number of different climates and while we have somewhat mastered that process, why gamble? Take fruit from farm to your home and skip all the intermediary refrigeration that can go awry. Success is juicy.