Potatoes are one of the most consumed foods on the planet, a genuine kitchen staple that shows up in everything from weeknight dinners to holiday feasts. Most people toss them into the fridge without a second thought, figuring cold equals fresh. Turns out, that instinct is dead wrong. Food scientists and public health agencies have been warning for years that refrigerating raw potatoes sets off a chain of chemical reactions that affect flavor, texture, and, in some cases, your health. Here is what the science actually says.
The Cold-Induced Sweetening Problem
When you stash your potatoes in the fridge, typically kept around 35 to 40 degrees Fahrenheit, their natural starches begin converting into sugar. This process, called cold-induced sweetening, might sound harmless and maybe even delicious, but it is bad news for regular white, yellow, or russet potatoes. The biology behind this is straightforward: potatoes are not built for environments that cold. Potatoes are high in starch, and when stored at low temperatures, the starch converts to sugar, a process known as cold-induced sweetening. As the starch turns into sugar, it can alter the flavor of the potato, making it unusually sweet and less desirable for many dishes.
Preserving potatoes in cold storage triggers the cold-induced sweetening process, or CIS, which converts starches to sugars, and processing tubers loaded with sugars results in darkened fries and chips. This darkening is not just an aesthetic issue. As the starch transforms into sugar, the flavor of the potato changes. Instead of that classic earthy, nutty flavor, you get a weirdly sweet undertone that throws off the balance in savory dishes, and the texture also suffers, as those sugary potatoes can get mealy and will brown too quickly when cooked.
The Acrylamide Cancer Link Explained by Scientists
With those sugar-heavy potatoes, the Maillard reaction does not just create delicious flavor, it also creates acrylamide, a potentially harmful compound that has been linked to cancer in animal studies. The European Food Safety Authority and other public health organizations have recommended minimizing acrylamide intake whenever possible. The connection between cold storage and acrylamide is not incidental. Acrylamide is a chemical substance formed when starchy foods such as potatoes and bread are baked, fried, grilled, toasted, or roasted at temperatures above 248°F (120°C). It is also present in biscuits, cakes, cereals, and coffee, and research has found that acrylamide causes cancer in animals, with the potential to do the same in humans.
In a landmark 2024 study published in the journal The Plant Cell, researchers at Michigan State University made a significant breakthrough on exactly this issue. Professors Jiming Jiang and David Douches identified the specific gene responsible for the cold-induced sweetening process and discovered the regulatory element that activates this gene under cold conditions. As Jiang explained: “We have identified the specific gene responsible for CIS and, more importantly, we have uncovered the regulatory element that switches it on under cold temperatures.” The European Food Safety Authority has consistently reaffirmed that acrylamide in food potentially increases the risk of cancer for consumers in all age groups, and the compound is classified as a Group 2A carcinogen.
How Refrigeration Ruins Texture and Flavor
The consensus among culinary experts and food scientists is a resounding “no” when asked whether potatoes should be refrigerated. Storing potatoes in the refrigerator alters their taste and texture, as the conversion of starch to sugar can create an overly sweet flavor detracting from the intended savory notes of dishes. Furthermore, the chilled environment can lead to a grainy texture, which is especially undesirable for starchy varieties used in baking and mashing. This is a problem that goes well beyond mere preference. The cool, humid conditions of a refrigerator create a perfect breeding ground for mold and rot. Even a seemingly healthy potato can develop spoilage if stored in a damp, enclosed space, and as a result, potatoes may begin to sprout prematurely or develop soft spots, leading to increased waste.
In addition to shortening their shelf life, refrigerating potatoes may alter their chemical structure in an unpleasant way. When potatoes are stored at temperatures less than 50 degrees, the starches in the spuds start to convert to sugars, leading to discolorations and off-flavors. Additionally, as noted by the U.S. Food and Drug Administration, fridge-stored potatoes will produce more acrylamide when cooked, a chemical that has been found to cause cancer in animals. The fridge, in short, is where good potato texture goes to die.
The Solanine and Sprouting Risk You Did Not Know About
If potatoes sprout during storage, they can contain potentially harmful levels of the solanine toxin. Previous research indicates that storing potatoes at low temperatures in light can increase solanine concentrations, and depending on the levels consumed, they can be detrimental to human health. Solanine is not something to dismiss lightly. Common symptoms of solanine poisoning include nausea, diarrhea, vomiting, throat-burning sensation, headache, and dizziness. In more severe cases, hallucinations, sensory loss, paralysis, fever, jaundice, and dilated pupils may occur.
Sun exposure can produce large amounts of a toxic chemical called solanine. Many people discard green potatoes due to their higher solanine levels. Solanine creates a bitter taste and causes a burning sensation in the mouths or throats of people who are sensitive to it, and it is also toxic to humans when consumed in very high quantities, causing nausea, vomiting, and diarrhea. A 2024 review published in the Journal of Experimental and Basic Medical Sciences further confirmed that exposure to light and physical damage can lead to an increase in solanine concentration in potatoes, and although methods such as frying, boiling, and cooking can reduce the solanine content to some extent, they often may not be sufficient to prevent poisoning.
What Food Scientists Say About Proper Potato Storage
In the pantry, potatoes can last for one to two months, according to Dr. Vanessa Coffman, director of the Alliance to Stop Foodborne Illness. That is considerably longer than most people expect, and it requires nothing more than the right environment. “Potatoes should be stored in a well-ventilated cool, dry and dark place, ideally between 45 to 55°F, otherwise there’s risk of potatoes going bad,” says Coffman. The guidance from multiple food safety organizations lines up on this point: keep them out of the fridge.
When stored between 43 and 50°F, raw potatoes will keep for many months without spoiling. This temperature range is slightly warmer than refrigeration and can be found in cool cellars, basements, garages, or sheds. Storing potatoes in these conditions can help delay the formation of sprouts on the skin, one of the first signs of spoilage. One study found that storing potatoes in cool temperatures more than quadrupled their shelf life compared to storing them at room temperature. Proper packaging matters too. Place dry potatoes in a breathable bag made from mesh or paper, or put them in a cardboard box. Potatoes require airflow to prevent spoilage, so storing them in anything that traps moisture, like a lidded container or resealable plastic bag, should be avoided.
The Breakthrough Research Reshaping How We Think About Potato Storage
In a breakthrough for the snack food industry, a team of scientists led by Michigan State University professors Jiming Jiang and David Douches discovered a key mechanism behind the darkening and potential health concerns associated with cold-stored potatoes. Their findings, published in the journal The Plant Cell, hold promise for the development of potato varieties that could be stored under cold temperatures and lead to healthier and tastier chips and fries. The implications extend well beyond industrial snack production. Reducing acrylamide formation in potatoes could have implications for other processed starchy foods, and additionally, cold-resistant potatoes could offer greater flexibility in storage and transportation, potentially reducing food waste and costs.
A separate 2024 study published in Food Research International (via ScienceDirect) supported these findings further. Three cold-induced sweetening-resistant varieties, namely Verdi, Lady Claire, and Kiebitz, were identified as able to be stored for up to four months at 4°C with limited increase in glucose content, and these varieties had good crisp color quality. Meanwhile, a comprehensive nutritional study found that storing potatoes in cupboards and boiling them is optimal for achieving a sustainable healthy diet, as it yields the optimal combination of nutrient retention and low environmental damage. The science, across the board, points in one direction: the pantry beats the fridge every single time when it comes to storing raw potatoes properly.
