My fridge has a power real-estate drawback. The difficulty isn’t leftovers, however condiments. Jars and bottles have stuffed the door and brought over the principle cabinets. There’s so little room between the chili crisp, maple syrup, oyster sauce, gochujang, spicy mustard, a number of sorts of sizzling sauce, and quite a few different condiments that I’ve began stacking containers. Squeezing in new objects is like concurrently enjoying Tetris and Jenga. And it’s all due to three little phrases on their labels: refrigerate after opening.
However numerous the time, these directions appear complicated, if not simply pointless. Pickles are normally stored chilly after opening, however the entire level of pickling is preservation. The identical is true of fermented issues, reminiscent of sauerkraut, kimchi, and sure sizzling sauces. Ketchup bottles are a fixture of diner counters, and vessels of chili oil and soy sauce sit out on the tables at Chinese language eating places. So why should they take up priceless fridge house at dwelling?
In the meantime, meals languish within the pantry after they would do higher within the fridge. Nuts develop an off style after a few months; spices fade to mud in roughly the identical time span. Just lately, a bag of flaxseed I’d purchased only a few weeks earlier went rancid and commenced to odor like paint thinner. Plenty of generally unrefrigerated meals may benefit from chilly storage, Kasiviswanathan Muthukumarappan, a refrigeration knowledgeable at South Dakota State College, informed me. But maddeningly, they aren’t labeled as such, whereas so many shelf-stable meals are refrigerated by default. The conventions for meals storage are stuffed with inconsistencies, losing not solely treasured fridge house, however generally additionally meals itself.
Judging by a visit to the grocery retailer, there are two sorts of meals: fridge meals and pantry meals. Pasta and granola bars, for instance, are stored at room temperature, whereas contemporary meals reminiscent of meat, dairy, and produce are stored chilly. A majority of these extremely perishable objects are outlined by the FDA as “temperature management for security” meals, and holding them beneath 40 degrees Fahrenheit slows the expansion of many dangerous microbes, which may trigger food poisoning. Exterior the fridge, pathogenic microbes develop quickly: In accordance with the U.S. Division of Agriculture, these meals shouldn’t be left unrefrigerated for even simply two hours.
However the binary—fridge meals and pantry meals—is simply too simplistic. Many condiments, for instance, exist in a murky center floor. Some mustards can sit out on a counter, whereas others are vulnerable to mould, Karen Schaich, a food-science professor at Rutgers College, informed me. Relishes, that are normally chopped pickled greens or fruits, also can develop mould or yeast fermentation if not refrigerated. Partially, it comes right down to their sugar content material: Microbes don’t thrive in acidic circumstances, however they typically do like some sugar. A broad rule of thumb is that “extraordinarily tart or bitter” condiments are normally protected to go away on the counter, so long as they aren’t additionally candy, Schaich stated.
Correct meals storage simply can’t be boiled right down to a single query—to sit back or to not chill?—as a result of the consequences of refrigeration are twofold. Past security, the fridge helps preserve a meals’s taste. It does this partially by slowing the expansion of spoilage microbes, which normally aren’t dangerous however produce revolting flavors and odors. The fridge additionally slows pure processes that degrade high quality. As soon as security is managed for, “chemistry takes over,” Schaich stated, referring to reactions that trigger meals to develop bizarre or gross flavors over months and even years.
The massive one is oxidation, which is answerable for many foul odors, tastes, and textures in meals, reminiscent of stale Cheerios and oil that smells like Play-Doh. It’s attributable to publicity to oxygen and accelerated by elements together with time, moisture, micro organism, gentle, and, crucially, warmth. Refrigeration retains meals tasting contemporary by controlling for the latter. That’s why merchandise like Heinz ketchup and Kikkoman soy sauce have labels saying they need to be saved within the fridge: Not for security, however for taste. Put them in your pantry, and so they’re unlikely to make you sick.
In terms of sustaining taste, one molecule is extra consequential than others. “It’s the fats that issues,” Muthukumarappan stated. Fatty meals—sure nuts reminiscent of pecans and walnuts, some sorts of oil—oxidize and go rancid, normally creating sour or bitter flavors and, generally, the tangy smell of metal or the waxy one of crayons. It is smart to refrigerate peanut butter, and nuts generally, Muthukumarappan stated. Higher but, retailer them within the freezer for those who plan on holding them for years. Grains are likewise susceptible to rancidity: Hemp seeds have a excessive oil content material and may oxidize within months, and so can some varieties of flour, Schaich stated—particularly, whole-grain flours reminiscent of rye and spelt. Storing them within the fridge is healthier than within the cabinet, she stated, however vacuum-sealing them to take away oxygen, then placing it within the freezer, is finest for long-term storage.
There are different causes you would possibly wish to put issues within the fridge. Spices don’t normally change into rancid, however their efficiency fades. A milk-carton-size container of smoked paprika I ordered a couple of yr in the past is now mainly purple sawdust. Outdated cumin smells boring, like pencil shavings. The flavour and pungency of spices comes from unstable oils, which too are susceptible to oxidation. Staleness, Muthukumarappan stated, is normally attributable to repeated publicity to the air—as in, frequently opening and shutting a spice jar. Protecting it close to warmth and lightweight can speed up the method. The freezer is beneficial for those who plan to retailer spices long run, supplied that they’re stored in hermetic containers. But when they’re going for use regularly, it’s finest for them to remain at room temperature. Protecting them chilly dangers condensation forming each time the container is opened, probably resulting in clumps, off flavors, and even microbial progress, Luke LaBorde, a food-science professor at Penn State, informed me.
In all my years of cooking, I can’t keep in mind seeing a ketchup bottle that stated it was okay to retailer at room temperature, simply as I’ve by no means come throughout a spice jar that was meant to be stored within the freezer. Storage directions on meals, or lack thereof, manifest a special actuality, one the place correct storage methods aren’t common information however insider data: There most likely received’t be any refrigeration directions on a bag of pine nuts, however if you know, you know. Anticipating each product to have detailed directions is unrealistic. An easier storage system, if a extra space-intensive one, may be to maintain all the things chilly by default. That method, not less than most meals could be safer, and presumably keep brisker. After I requested Muthukumarappan whether or not any meals would style higher if saved at room temperature, he stated he couldn’t consider any. But there’s nonetheless vigorous debate over whether or not tomatoes, bread, eggs, butter, and olive oil style finest at room temperature.
The fridge-pantry dichotomy won’t ever totally embody the murky science of meals security, and the specialists don’t at all times agree. Even the foundations for produce aren’t completely clear-cut: All sliced fruit, however not all entire fruit, ought to be stored chilly—particularly sliced melons. Not like most fruits, melons aren’t very acidic, making them extra hospitable to pathogenic microbes, LaBorde stated. Garlic is protected for a number of months when stored at room temperature, however do-it-yourself garlic-in-oil carries the risk of botulism unless refrigerated.
There’s just one method to reclaim our fridge house and keep away from rancid nuts, stale oats, and moldy jellies: pondering past the fridge-pantry binary. Particularly, think about how lengthy and the place you propose on storing meals. It’s not at all times simple.:Purchase in bulk from Costco, the place you may get a five-pound bag of walnuts and a gallon of mayo, and meals can simply linger—or be forgotten—in a moist pantry for months, even years. Nonetheless, if a bottle of ketchup goes to get used up in every week of summer season barbecues, you may let it hang around on the counter. Went nuts when the walnuts went on sale? Freeze some for future you.
The science of meals storage was broadly recognized a number of generations in the past as a result of it was taught in American colleges, Schaich informed me. Now we’re on our personal. Though we’re unlikely to ever grasp all of its complexities, understanding it just a bit extra has some benefits. Disregarding the advice to refrigerate an open jar of capers gave me a frisson of pleasure—not simply because it felt like breaking an imperfect rule, however due to the house it opened up in my fridge.
