food-safetypotatoes
I kept several potatoes in a box dark cool cellar. Now, after 6 months, I am surprised to see that they grew a lot of sprouts, and among them, many "baby potatoes", with radius between 1 and 10 milimeters. The "mother potatoes" look and smell OK, but they feel softer than usual.
I wonder if there is anything here that can be cooked and eaten?
I have read that the sprouts themselves are poisonous, and the softer potatoes are also unsafe. But what about the baby potatoes – are they safe?
Not safe enough for me to try it. Potatoes actually contain a very dangerous toxin called solanine. This toxin is concentrated enough in the green parts in the plant to cause solanine poisoning. This includes the sprouts/eyes, and the potato itself if it's green.
This article from the New York Times health guide indicates that it is something to be taken seriously. Per this article, if the sprouts have been removed, and the potato is not green then it is safe to eat as far as solanine poisoning is concerned.
However, a potato as far gone as you have described sounds disgusting. A soft potato is on its way to going bad. Where I am from, potatoes are cheap enough that it's just not worth the gross factor for me to eat a potato that has 10 cm sprouts and is squishy. I do eat potatoes that have little nub sprouts on them and that are slightly less than firm, after removing the sprouts of course.
I imagine the problem is that the cells of the potatoes have absorbed too much water.
There are a few ways you can help avoid this:
Update 1 (Overcooking): Although what I have written will help avoid water logged mash, the simplest answer is in the comment from SAJ14SAJ: the potatoes were overcooked. Here in Sweden it is common to use a thin metal skewer to test potatoes for doneness (see image). The skewer is about 6 inches long and 2mm thick. This makes it long enough to reach the center of pretty much any potato and thin enough not to crack or otherwise visibly damage the potato when testing (not that this matters for mash). In Swedish these are called potatisnålar (literarily potato-needle).
When the skewer can be pushed into the center of the potato without resistance, it is done.
Update 2 (Potato Variety): Some potato varieties have a higher water content, and the water content can differ within a variety. With that in mind, red potatoes are not necessary a good choice for boiling unless you try the starch gelling tip above.
You should look for potatoes with a medium to high percentage solids. The potato varieties available differ widely from country to country so I won't recommend a specific variety, but you can do a simple test to check the solid content of your potatoes using a saline solution with a 1:7.5 salt to water weight ratio and a clear container. If the potato floats about the middle of container, it is around average solid content. If it floats higher, it has a high water content. If it sinks lower, the solid content is above average.
Best Answer
Planting will get you a better return. Cut the potatoes up into sections with a sprout each, let the cuts callus at 70 F/21C for a few days, and plant.
If you remove the sprouts and the potatoes are not green, or any green parts are removed, they should be safe, if not of particularly good quality.
Planting the sprouted ones and buying others to eat would be your best bet, better quality, and not too costly. Next year, put some apples in the root cellar with the potatoes to help prevent/reduce potato sprouting during storage.
In the well-managed root cellar we're supposed to somehow find time to to go through every couple of weeks to check for and remove the various sprouting or spoiling food before the process gets too far along. I can't say I have arrived there myself yet...but if you at least look for the sprouted ones when you are grabbing tubers to use, you can remove small sprouts from firmish potatoes and use them up, and be aware if the whole batch is sprouting away and needs to be used up soon, before it gets to this point.