May 25, 2011. The leaves will exhibit dark brown water-soaked spots; later the spots become blackish and later affected tissue drops leaving a hole in the leaves; black raised specks may appear on the tubers. I had many potatoes I wanted to preserve for a long time. Russet Potatoes - Bluish Black Spots ... we had a large number of potatoes that had nasty bluish black spots inside when we cut them open for service. Because this injury is always the result of bruising, including pressure bruising, internal symptoms may be associated with flattening or other signs of mechanical injury on the tuber surface. Next Last. Though all recovered, in a … Exposure to sunlight can cause green spots to form on potatoes. Symptoms: Internal black spots usually are at the tuber's stem end. 1899: After eating cooked potatoes containing 0.24 mg of solanine per gram of potato, 56 German soldiers experienced solanine poisoning. Cool potatoes slightly before removing skins. Desiccation (pressure flatting) increases black spot when potatoes are handled. The same procedure applies to dark spots or bruises that may occur on the skin of a potato. It's impossible to tell which potatoes will turn dark, but the discoloration does not affect flavor, texture, or nutritional value. Cholorgenic acid combines with the iron in the potato to produce the grey or dark appearance. Cooking Discussions. Reasons Potatoes Turn Black After Cooking: Potatoes occasionally turn gray or dark after they are boiled; this color change may be caused by the conditions under which they were grown or stored. 12 years ago. Bruising increases rapidly when the pulp of potatoes being harvested drops below 47 to 50°F (8.33 to 10°C). After a few hours of exposure to cold temperatures, the starch in potatoes starts to turn to sugar. Anyone have any ideas why that happened? The effect you noticed is called "after-cooking darkening," and it can happen with any kind of cooked potatoes in any kind of pan. Cook them whole whenever possible as most of the nutrients are next to the skin, and skins are easier to remove after they have been cooked. Freezing injury is much worse, leaving the tuber soggy and then chalky as the water dissipates. Method – 4: (Potato with Pomegranate) Sweet potato: rotten beneath the skin after long storage . Mold and black rot. The black dots on the potato leaves may be a bacterial spot or bacterial speck. Join the discussion today. Or were they badly bruised and we didn't know it until after they were baked and … You can remove the spots, and cook and enjoy the rest of the sweet potato. Thread starter IB4Fun; Start date May 25, 2011; 1; 2; Next. Black dot disease of potato, caused by the fungus Colletotrichum coccodes, is generally considered to be a weak root pathogen of potato.Recent studies in New York and elsewhere have revealed, however, that this disease must be considered as part of the total disease complex affecting potato. Usually the potatoes I keep in my kitchen get rotten after a month or two (and I don't have a cellar to keep them cool), I decided to dehydrate them. As for any developing sprouts, those can be cut off too. Pierce skin with fork. As the potatoes deteriorate, their odors change to moldy and bitter. These spots are called internal black spot and are essentially bruising that occurs from the potatoes lying against each other for an extended period of time. With raw potatoes, sweet potatoes, apples, avocadoes, etc., when you peel them and they are exposed to oxygen, the oxidation process begins turning them brown/grey. If it's smaller, toss the whole spud into the compost. And, fortunately, this potato never got so cold that it froze. Black spots should be pared & discarded, not eaten. This is very annoying to caterers or anyone selling precooked potatoes. She fried them in butter. Some potatoes are more susceptible to this discoloration and are influenced by the soil and climate in which the potatoes were grown. I have planted 3 different types of potatoes. The green parts are full of solanin - which is poisonous in large quantities, but just unpleasant to eat in small amounts. This sugar caramelizes and begins to darken, giving the cooking potatoes a brown appearance. (Boo.) On a larger tater, cut it off. Dry at 125 F / 52 C until crisp. What causes black spots on sweet potatoes? Any discolored area can simply be cut away. Thinking they’re only for Thanksgiving dinner. The potato may look fine from the outside, but if you cut it across or after peeling it, you may see a black spot in the middle. Home Cooking. This browning is the result of another reaction that also does not render the potatoes unsafe to eat. Best way to bake them next time is wrap them in foil unpeeled then bake at 350 till done. Once you notice that soft brown or black spots developed on sweet potatoes surfaces, you can be sure that tubers have begun to spoil. Food & Cooking . This type of discoloration sometimes occurs in cooked potatoes and appears as a gray-blue-black area as the cooked potato cools. Darkening may also be caused by a natural reaction with the iron in the potato. I hadn't planned to dig them just yet, but the deer have eaten nearly all the tops. It's impossible to tell which potatoes will turn dark, but the discoloration does not affect flavor, texture, or nutritional value. After boiling, the dark black spots seemed to permeate the flesh. When I peeled it, I noticed there were deep darkish furrows in the potato, like spots where sprouts had been but were knocked off. The exception is mold spots; if a sweet potato has begun to mold, throw it away. Black spot occurs in the tuber flesh just beneath the tuber periderm and appears as gray to black circular areas with diffuse borders. Adding lemon juice during cooking prevents this reaction and eliminates the problem. I ended up cutting 1" wedges, and washed the white stuff off, and nuked them and tasted fine. Apply it on the dark spots using a cotton ball and rinse off after 20 minutes. Since spots are located only superficially, you can use the veggies after cutting them away. Latest Discussions. Place potatoes in a pan and cook in an oven heated to 375° F for about 45 minutes or until tender. The 20 Best ALDI Finds for November Are All About Cookies & Thanksgiving . The moldy looking spots are a more serious condition that can develop from the bruises, called fusarium. For more take a look at this page: Typically, it happens if you boil (or fry) potatoes and then store them—they will sometimes turn black or purple over time if they are exposed to air. Sep 13 # 1 of 4. The dark areas have a bitter taste and are not palatable. Joined May 25, 2011 Messages 13 Reaction score 0 Points 22. These spots do not indicate spoilage, and you can simply remove them before cooking. Do it once a week. This carmelization may change the taste of the potatoes. She mashed this all together and formed patties. White, smooth-skinned cultivars are more susceptible. The rot can occasionally spread to the cortex of the sweet potato. After they cooled she combined them with one egg and mixed in about two tablespoons of flour and some salt (about 1/4 teaspoon). Hello, I am very new here and to growing a garden. It doesn't taste different, but it looks unpleasant. ourhappyhome. References. Mold may appear as fuzz or a few dark spots that are brown, black… Black spots in potatoes New potatoes have a starchy, earthy smell. Against my better judgement, I didn't cut them out. Potatoes can turn black from oxidation, black spots below the skin, storage after insufficient cooking. They started eating the tops about 10 days ago, but I left the plants hoping they would recover. Bacterial infections are often brought on by wet conditions and war, temperatures. Potatoes. Black spot in potatoes. Cook… 10 / 10. Also, you can exclude lemon juice in the above process and apply a mix of potato juice and honey on black spots and rinse off after 15 minutes with normal water. I'm not sure if it's mold or fungus or something else completely. The only problem is that the microwave cooks the potato unevenly, remaining hard and lumpy in some spots while overly soft and mushy in others. 1 of 2 Go to page. As I already mention, potatoes sprout little growths after a while. In my case, I will discard the leftover soup, as it sat for a few days with the blackened potatoes. White Fuzzy Stuff On Potatoes Page 1 . Go. Additionally, if you ever spot mold on cooked potatoes, you should dispose of them immediately. If I moved my finger across the spots, they absorbed back into the sweet potato . Also, look for any weird growths on the peel and throw tubers away if you see them. Use in soups, casseroles, and recipes using potatoes.” (Page 340) Excalibur. Similarly, small brown or black spots on your sweet potato do not necessarily indicate that it has spoiled. The "black spot" is most likely caused by a fungus. According to McGreger, if the spots of decay are purely superficial, they can be cut away. Thread starter #1 I. IB4Fun Leafing Out. I have Russet, Yukon Gold and red potatoes. I cut another wedge off and the same thing happened. just discard the dark spots when you peel them. Preparation: “Wash potatoes to remove dirt; peel if desired. White Fuzzy Stuff On Potatoes - Cooking Talk - Cooking Forum - Spice Place. Just know that sprouts do pull nutrients from the sweet potato, so you’ll end up with a cooked spud that’s of inferior nutritional value. Sweet potatoes can be cooked in a microwave oven to save time. Around them, the flesh is very fibrous. Well, the deer kept coming back and now I have to dig them. Sweet potatoes generally begin to spoil by developing soft black or brown spots. So I grinded them in a food-processor and put in a food-dehydrator in 65 Celsius. Sweet potatoes with black rot will develop larger spots that darken and have tiny black fungal structures with stalks. I cut into this sweet potato and a few seconds later, these crazy white spots appeared. 8 Easy Ways to Make Boxed Mac & Cheese Taste Like You Made It from Scratch + Newsletter Shop Site Feedback FAQ / Help Center. Taste of Home . Sometimes this is exaggerated by the metal of the fork or knife, especially older ones where the material had some iron in it. I just dug a wonderful harvest of large sweet potatoes. Lesson learned; don’t pierce the potatoes too far in advance. Savorykitchen October 2, 2010 same rule - sorta - cut away anything that's green and sprouty. There were a bit dark around the corner. “After cooking darkening” occurs in some potatoes and is the result of an imbalance of naturally occurring acids. The rest should be fine. Spice Place Cooking Forum > Cooking > Cooking Talk > Thread: White Fuzzy Stuff On Potatoes Posted By: Ashworth3715 . Luckily, you don’t have to cook sweet potatoes every night; once cooked, they’re good in the refrigerator for up to a week! Should we not have pierced them until just before being placed in the ovens? let cool then peel (to check to see if done quickly press finger into potato thickest partif it embeds imprint they are done or use thermometer 170 internal temp) These cause a sweet, sickly fruit smell and may invite insects to transmit the disease. The black spots are where the potato oxidized when exposed to air. The potatoes are still safe to eat, just cut the spots away. The same goes for potatoes that turn black after boiling. Reasons Potatoes Turn Black After Cooking: Potatoes occasionally turn gray or dark after they are boiled; this color change may be caused by the conditions under which they were grown or stored. So don’t let those little brown/black spots deter you—scrape ‘em off . Read the Sweet Potatoes turning black discussion from the Chowhound Home Cooking, Potatoes food community.