Raw potatoes should be firm to the touch with tight skin that's free of large bruises, black spots, or other blemishes. If a potato has become soft or mushy, you should throw it out. Though it's normal for potatoes to smell earthy or nutty, a musty or moldy odor is a hallmark of spoilage.
The short answer is yes. Potatoes that have sprouted are still OK to eat, but only once you've removed the sprouts.
What happens if you eat bad potatoes? Bad potatoes contain high levels of solanine and can cause solanine poisoning. Symptoms include nausea, diarrhea, stomach cramps, vomiting, headache, dizziness, among other things.
So when is it time to toss a tater? University of Illinois Extension recommends that soft, shriveled, or wrinkled potatoes with or without sprouts should not be eaten.
If a potato has become soft or mushy, you should throw it out. Though it's normal for potatoes to smell earthy or nutty, a musty or moldy odor is a hallmark of spoilage. Sometimes, a potato might have a blemish or bad spot on the inside that you can't see from the outside.
It may irritate the mouth resulting in a bitter taste and possibly a burning sensation. If someone swallows a large amount, it can irritate the stomach. Causing nausea, vomiting, diarrhea, abdominal pain, headache, and flushing.
Greenish potatoes with little white sprouts, or eyes, occur when the potato is ready to start its next cycle of growth. Those little tubers can be planted and grown into new potato plants. But can you eat them? The short answer is no, you shouldn't eat potato sprouts.
The eyes are sprouts that can be planted to grow potato plants. However, if you'd rather eat potatoes than grow them, remove the eyes and cook the potatoes well.
Potatoes can last for up to several months in a cool pantry. If stored at room temperature, they are best if eaten within one to two weeks. Once cooked, keep them in the fridge for no more than three days.
Solanine poisoning
Ingestion of solanine in moderate amounts can cause death. One study suggests that doses of 2 to 5 mg/kg of body weight can cause toxic symptoms, and doses of 3 to 6 mg/kg of body weight can be fatal.
In this environment, and at the right temperature, spores on the potato can germinate and grow - producing their deadly toxin. Several cases of foodborne botulism caused by foil wrapped baked potatoes have occurred including a large outbreak in 1994 in Texas. In that outbreak, 30 people were affected.
CONSTITUTION: Solanin is removed from potatoes by dipping the potatoes in vinegar of 30-60 deg. C, containing 0.3-1.0 vol% of acetic acid, for 2-5 minutes.
The potatoes might have been harvested in heat and started perspiring, just like a human might, as it is still a living organism. If trapped in a bag or box then the moisture can cause the potatoes to be wet or sealed up with no ventilation and could actually mold if left that way too long.
Control. Solanine is not removed by boiling, but it can be destroyed by frying. Solanine poisoning is uncommon as cooks and the public are aware of the problem and tend to avoid green potatoes, in any case, consumption of up to 5 g of green potato per kg body weight per day does not appear to cause acute illness.
The evaluation of solanine was done by standard chemical tests. The later process performed was thin layer chromatography which was performed by using chloroform: Menthol: Ammonia (7:3:0.5) solvent system for the analysis of glycoalkaloid solanin. IR graph of solanine resembling various peaks was obtained.
If your potatoes smell bitter, don't eat them, experts say.
Thankfully there are two common signs that a potato has developed dangerous levels of solanine: they can give off a bitter smell, and their skin may turn a shade of green.
Boiling does kill any bacteria active at the time, including E. coli and salmonella. But a number of survivalist species of bacteria are able to form inactive seedlike spores. These dormant spores are commonly found in farmland soils, in dust, on animals and field-grown vegetables and grains.
Vegetables and fruit, particularly those grown in soil, can contain botulism spores. Home-canned and low-acid foods (corn, green beans, mushrooms) are also most likely to contain the bacteria. It takes 12 to 36 hours for botulism to develop.
Cases of botulism from foil-wrapped baked potatoes are rare, but they do occur. One example occurred in El Paso, TX, in 1994, the largest botulism outbreak since 1978.
Solanine is heat stable it decomposes over 200°C (about 240-260°C afaik) and it is not (poorly) water soluble.
Solanine is a bitter-tasting steroidal alkaloid saponin that has been isolated from all nightshades, including tomatoes, capsicum, tobacco, and eggplant. However, the most widely ingested solanine is from the consumption of potatoes. Potato leaves, stems, and shoots are naturally high in this saponin.
There is no cure or known remedy.
When stored in a cool, dark place, (warmer than the fridge but colder than the average temperature of your kitchen) whole, uncooked potatoes can last up to two months. At room temperature, on the counter, for example, potatoes will last up to two weeks.
According to the New Scientist, we shouldn't be storing raw potatoes in the fridge because it can lead to the formation of acrylamide during cooking. At low temperatures, an enzyme breaks down the sugar sucrose into glucose and fructose, which can form acrylamide during cooking.