Proper storage is important for maintaining potato quality and extending shelf life. Different storage methods significantly impact their taste, texture, and chemical composition.
Storing Potatoes in the Refrigerator
Storing raw potatoes in the refrigerator is generally not recommended. Cold temperatures, typically below 50°F (10°C), cause starch to convert into sugars, a process known as cold-induced sweetening. This leads to a noticeably sweeter taste and can cause potatoes to darken or brown excessively when cooked at high temperatures, such as frying or roasting.
Beyond changes in taste and color, refrigerating raw potatoes can also impact acrylamide formation. Acrylamide is a chemical compound that forms in starchy foods when cooked at high temperatures (above 248°F or 120°C). The increased sugar content from cold storage can lead to higher acrylamide levels when potatoes are subsequently fried or baked. While some studies suggest home refrigeration might not materially increase acrylamide potential compared to cool, dark storage, official guidance often advises against it.
Cooked potatoes, however, should be stored in the refrigerator. They typically last for about 3 to 4 days when kept chilled.
Ideal Storage Conditions for Potatoes
Optimal storage conditions for raw potatoes are cool, dark, and well-ventilated. An ideal temperature range is between 45°F and 55°F (7°C and 13°C), slightly warmer than typical refrigeration. This helps prevent premature sprouting and slows spoilage.
Good ventilation is important to prevent moisture accumulation, preventing mold and spoilage. Storing potatoes in an open bowl, a paper bag, or a mesh bag allows for adequate air circulation. Avoid storing them in sealed containers like plastic bags without ventilation. Keep potatoes away from direct sunlight or heat sources, as warmth can accelerate ripening and spoilage. Store potatoes separately from fruits, especially apples, as these fruits release ethylene gas, which can cause potatoes to sprout more quickly.
Signs of Potato Spoilage
Recognizing signs of spoilage indicates if potatoes are still suitable for consumption. A soft or mushy texture is a common indicator, as fresh potatoes should be firm. Wrinkled or shriveled skin also suggests the potato has lost moisture and is past its prime.
Potatoes can develop green spots when exposed to light. This green color is due to chlorophyll, but it often indicates an increased presence of solanine, a naturally occurring glycoalkaloid, harmful in large quantities. While small green areas can be peeled away, an extensively green or bitter-tasting potato should be discarded.
Sprouts, or “eyes,” are another sign of aging, indicating the potato is attempting to grow. Small sprouts can be removed, and the potato may still be edible if firm and free of extensive greening. However, if sprouts are long or the potato is significantly shriveled, it is best to discard it.
A foul, musty, or moldy odor is a clear sign of spoilage, even if visible mold is not present. If mold is visible, particularly on cooked potatoes, discard the potato entirely, as mold spores can spread beyond what is visible. For raw, firm potatoes with small mold spots, trimming the affected area plus an inch around it might be an option, but discarding the potato is the safest approach if there’s any doubt.