Is it possible that a slightly rotten potato could taste far better?

June 26, 2012 10:43 AM

I cooked some near-rotten potatoes and they offered a flavour far surpassing other potatoes. I long to taste it again.

I had some red potatoes lying around that I hadn't gotten around to cooking. I decide to make poutine with them with some fresh cheese curds I have. I start to make my poutine recipe, and when I wash and begin to cut the potatoes, oh god no, the smell, the smell! I suspect they're rotten, but the skin is still reasonably tight and despite one or two points of soft rot I cut off, they are still fine with no growths. My cheese curds are too fresh to pass up and I don't want to get other potatoes, so OK, lets proceed.

What followed was one of the most surprising gastronomic experiences of my life, these potatoes are incredible! They have a taste I'm simply not equipped to describe, surely nothing like I've ever tasted in a potato or poutine in a life of eating reasonable amounts of both. I'm absolutely floored by the very peculiar experience of eating these spuds!

OK, so I try and make the recipe a few days later, buying the same potatoes, curds, and using the same oil and method. But they don't taste the same, they just taste like ordinary potatoes. I try a few more times and I can't get any result but the same regular taste.

I'm beginning to suspect it was the fact that the potatoes were right at the point of spoiling that gave them their extraordinary taste. I'm now now leaving out some potatoes to experiment at various stages of spoiling to replicate the taste. My question is; is there any kind of basis to this? Could a not overly rotten potato have a very different flavour from other potatoes? Is there any precedent for foods tasting considerably better in such a state? From my preliminary research I've only found people discussing how to avoid rotten potatoes, and the idea that when eating such plants (fresh == better) is strongly ingrained in me. Is there anything grounding this possibility?

This is a picture of the style of potato I'm using, so called "organic type"

Here's my method:
- Olive oil and butter in pan, heated
- Cut potatoes, put into oil, leave on low-med heat until one side cooked to satisfaction
- Rustle the potatoes around to cook the other edges after the one side is done & add pepper, salt, other spices
- Put on curds & perhaps other toppings when done

posted by Algebra to food & drink (19 answers total)

If they smelled off but were firm and had tight skin, I wonder if they were actually rotten.
posted by clockzero at 11:02 AM on June 26, 2012

Did you perhaps buy the special potatoes at a local farmers' market? Variations in soil, in fertilizer, in climate will affect the taste of any food grown. They may also have been a slightly different variety of potato, even though they looked the same. Or maybe even hanging around your kitchen ripened them more, just the way a tomato ripens and gets more flavorful if you let it sit for a day or two after buying it.
posted by mareli at 11:14 AM on June 26, 2012

I've never heard of a rotten potato still being firm to the touch with taut skin. In my experience, bad potatoes don't just go wrinkly and squishy, they drip a milky white fluid.

But potatoes will take on other smells in your pantry, if they are stored with other strong-smelling items. It might not be the potatoes themselves, but whatever they were stored with that made the difference. I'd investigate your pantry a little.
posted by LN at 11:24 AM on June 26, 2012

It could also be related to the moisture content. I'm not sure what exactly happens to potatoes when you leave them out, but if they got more moist/less moist, that would change the way that they absorb the flavors when you fry them in butter and oil.
posted by specialagentwebb at 11:26 AM on June 26, 2012 [1 favorite]

By the way, what did they smell like? Did they smell strongly rotten, like a moldy wet dirt kind of smell that potatoes get when they go off? Or was it strongly oniony or something else?
posted by LN at 11:26 AM on June 26, 2012

How were they stored? I wonder if they weren't all that rotten, but smelled weird from long storage and some of their starch being converted to sugar, and bacteria/mold feeding on the sugars (fermenty smell), which happens to any potato stored long enough at relatively cool temperatures. They will taste noticeably sweet, and while most people would consider this a defect, maybe you like it and it works particularly well with poutine?
posted by slow graffiti at 11:30 AM on June 26, 2012 [3 favorites]

Potatos are ever so slightly toxic (the greens of the plant moreso), and it wonders me if old potatos might not be just a little bit more toxic so that it had a mild effect on the taste. Most likely not, but it is something to think about.
posted by Jehan at 11:40 AM on June 26, 2012

"Several different glycoalkaloids are produced naturally by potatoes, the most common being solanine and chaconine. Low levels of glycoalkaloids produce desirable flavour in potatoes. However, exposure to elevated levels of glycoalkaloids when eating potatoes can cause a bitter taste or a burning sensation in the mouth - indicating a state of toxicity. Glycoalkaloids are not destroyed by cooking; even by frying in hot oil. The majority of this natural toxin found in potatoes is in the peel, or just below the peel. Greening of the potatoes may be indicative of the presence of the toxin. Red skinned or russet potatoes may camouflage the greening."
posted by cromagnon at 11:40 AM on June 26, 2012 [4 favorites]

Fermentation specialist Sandor Katz notes: "There is this creative space between fresh food and rotten food where most of human culture's most prized delicacies and culinary achievements exist." I wonder if those potatoes were a bit fermented.

I've been making sourdough bread for a long time and almost everything I've read about the process at some point will mention that if you don't have access to a "starter", you can make one with potatoes as they tend to be covered with wild yeast, just under the skin.

I'm not sure that's what you're tasting, but it seems possible.

I doubt it's glycoalkaloids as they tend to make the potatoes taste terrible, not better.

If you want to experiment, try soaking freshly peeled potatoes in water with a little sugar and a little salt, less salt than sugar. Not too long, but more than an hour. Then cook them the way you did previously.

Good luck!
posted by Toekneesan at 1:11 PM on June 26, 2012 [3 favorites]

Toekneesan: try soaking freshly peeled potatoes in water with a little sugar and a little salt, less salt than sugar

If you're recommending that as a way to get the yeast active, then drop the salt... salt kills yeast, and even a little will at least slow their growth. If you were just recommending that as seasoning, like a brine, then ignore me.
posted by gilrain at 1:51 PM on June 26, 2012

It grosses me out, but my mother-in-law takes the soft-ish potatoes that have been sitting in my cold storage for 10+ months, knocks the foot-long sprouts off of them, peels off all the greenish bits, and grates them into potato pancakes. And they really are the best-tasting potato pancakes in the world, if you don't think about where they came from.
She claims that the drier and older the potato gets, the better it tastes, so there you go.
posted by bluebelle at 2:35 PM on June 26, 2012 [2 favorites]

I think it's entirely possible your nearly rotten potatoes tasted better because they were nearly rotten, and in that connection I'm really intrigued by something Toekneesan said:

I've been making sourdough bread for a long time and almost everything I've read about the process at some point will mention that if you don't have access to a "starter", you can make one with potatoes as they tend to be covered with wild yeast, just under the skin.

Sourdough starter can be a culture of lactobacillus alone, but usually has a symbiotic combination of bacteria and yeast (I thought it was always bacteria alone, so I'm glad I took the time to find a link!), and there is a traditional potato product from the Andean altiplano-- the geographical center of diversity and presumed origin for the potato-- which almost has to be at least partially autofermented: chuño

After harvest, potatoes are selected for the production of chuño, typically small ones for ease of processing. These small potatoes are spread closely on flat ground, and allowed to freeze with low night temperatures, for approximately three nights.

Between the freezing nights, they are exposed to the sun, and they are trampled by foot. This eliminates what little water is still retained by the potatoes, and removes the skins, enabling subsequent freezing.

After this, they are exposed to the cold for two additional nights.

Starting from this basic freeze-dry process, two varieties are obtained: ...

Following your lead, I think I'll try wrapping some potatoes in paper towels and performing a couple of freeze-thaw cycles and see what happens.
posted by jamjam at 3:10 PM on June 26, 2012

Depending on how they are stored, potatoes can become sweet as they age as the starch is converted to sugar. I'd try making your recipe with sweet potatoes to see if the extra tastiness could be attributable to sweeter than normal potatoes.
posted by 6550 at 6:45 PM on June 26, 2012 [1 favorite]

As someone who once rotted potatoes for a living (I worked in a potato pathology lab) I can attest that some kinds of spud rot can smell really bad. Even the non-smelly organisms make the spud go disturbingly soft. I wonder if the bad smell came from the rotten bits and the change in flavor came from the increasing sugar content from aging (as 6550 pointed out).

I did find this mesageboard post by someone who also enjoys the flavor of a well-aged potato.
posted by gamera at 7:24 PM on June 26, 2012

Some further details:

- The potatoes were purchased in Kensington Market in Toronto, this isn't exactly a farmer's market, but I would expect a higher than usual variance between crops.

- The potatoes were stored near my kitchen wine pantry, a dry area out of direct sunlight. However, due to some high temperatures in Toronto recently and my sunny kitchen, there may have been temperatures as high as ~35 in the area for brief periods. This may have helped lead to fermentation as mentioned, and perhaps drying the potatoes out more than usual.

- The smell- I would say it was a very peculiar odor, not entirely unpleasant, but not what one would expect emerging from food-stuffs. It was strong, but not overpowering, and not released in a constant aura, that is, it came in periodic "whiffs" so to speak. It had an inquisitive quality- a tone about that invites an intentional further smelling. I would say it was somewhat like certain mushrooms, perhaps not so far from fungal odors, but somehow not entirely so far from a rotten, say, mango, however, it was entirely devoid of what I can't describe better than a "bad smell," that is, it was not a smell like perhaps garbage or rotten fruit which gives you a visceral "this is bad" feeling, it was only a peculiar and unexpected bouquet. I would not rule out an odor of fermentation or the production of yeast.

As far as the comments on development of yeast, glycoalkaloids, sugars, and fermentation goes- this stuff has me rather curious! I think there really may be something to creating this special flavour!
posted by Algebra at 7:45 PM on June 26, 2012

If you want to try a slightly different potato food experiment, I suggest putting some potatoes in the refrigerator for a couple weeks.

Most places tell you not to do that because it turns some of the starches to sugars, but this is exactly what makes them so delicious. Especially when simply fried in butter or oil, the slightly sweet taste can be so much better than regular potato taste.
posted by that girl at 1:00 AM on June 27, 2012

The fact that you had incredibly low expectations may have improved the flavour.
posted by justsomebodythatyouusedtoknow at 1:37 AM on June 27, 2012

As a natural part of their growth cycle, potatoes (like most-to-all tubers) initially store hard-to-consume starches, and then, as Spring approaches, gradually convert them to simple sugars. This frustrates parasitic fungi/bacteria/bugs/etc during the winter, while making the quick energy available when the sprouts need them.

Your long-stored potatoes probably went through this conversion cycle. The same variety of potato can taste starchier or sweeter, depending on when it was bought (and how stored).
posted by IAmBroom at 9:46 AM on June 27, 2012

The potato pictured doesn't look bad just a little old. Never eat potatoes that have green skin.
posted by boby at 1:12 AM on July 2, 2012