It would appear that over time people have lost touch with the imperfection of natures bounty. Whilst the humble potato is a great source of complex carbs it harbours some real gotchas. The main toxin concerned is the glycoalkaloid solanine, this toxin is present in the leaves stem roots and outer few mm of the potato itself. There are many traditional steps of preparation that alleviate this concern, but the fact that in australia we sell potato skins as a pub served dish is disturbing.
Basically the way to avoid this toxin is as follows:
In relation to the pealing of potatoes the end of the peeler usually comes with a tool for taking out the eyes. I personally like perpendicular peelers for safety and comfort.
As for the greening, This is indicative of light exposure. The light exposure creates both chlorophyl and solanine in the potato on most varieties. So the greening is just an indicator that this is a risky potato. There are varieties of potato that produce solanine on light exposure but little chlorophyl, These are dangerous in shopping centres as you have no idea about solanine production levels due to fluro lights. This in my opinion means that all potatoes should be black bagged....but that is just my opinion.
This is just a summary of my limited knowledge and please take it with the understanding that I am but a humble Vegan and mostly educated in fields far from biology. I hope this is of use and welcome the input of others. I am particularly interested in the history of cultivation and varieties with different solanine potentials..cheers
Despite the presence of solanine in green parts, potatoes are a wholesome, nutritious food that has nourished people for thousands of years. I agree with keeping them in the dark, and not eating green parts or eyes. I don't know that you really have to discard the water they are cooked in, or peel them. I read that there are a lot of nutrients in the skin. I eat the skins and I don't discard potato water, such as in soup.
Symptoms of solanine poisoning are here: Solanine poisoning is primarily displayed by gastrointestinal and neurological disorders... nausea, diarrhea, vomiting, stomach cramps, burning of the throat, cardiac dysrhythmia, headache and dizziness. In more severe cases, hallucinations, loss of sensation, paralysis, fever, jaundice,dilated pupils, hypothermia and death have been reported.
I've personally never had these symptoms from eating potatoes, and I eat a ton of them. I think a lot of people are much less careful than me, and have no problems. I think it's important to know how to cook safely, but this does not worry me. The bigger problem is cooking them in oil and salting too much, like french fries and potato chips. I love making potato soup, using a vegan broth and potatoes and onions.
I LOVE potato pancakes and make them all of the time!
I just put a vegan margarine on mine. My family always put apple sauce on the.
I too rely on potatoes, as with most toxins you do not want to wait for toxic symptoms in order to reduce the dose. The skins should be removed as you are just increasing the stress on your liver, this applies to many vegetables. If you consume the potato water you are consuming the glykoalkanoid for no real reason. Most people ignore the fact that it is likely that their diet will be responsible for there death. This even applies to smokers and drinkers, As in thier case it will not assist in preventing cancer, It is highly recommended that smokers and drinkers consume much higher levels of vitamin C than the normal person to bind to all the fee radicals in their body, With a good diet a smoker or drinker has a far better chance of survival. Although one would be far wiser to learn the irrationality of his or her ways and adopt a lower toxin life ASAP.
Love the recipe I will Give it a go, I will try to come up with a vegan version and submit it back to you.
What I use to substitute egg is surface fried tofu in little cubes, lightly seared on each side in a skillet with a little canola oil at as low a temp as I can whilst still getting a nice searing.
I also highly recommend nuttlex pulse margarine with plant sterols added, it is the only vegan plant sterol enriched marg in OZ. has next to no trans fats compared to all other brands of marg and very low sats. Still not sure abut its stability for cooking?
You actually don't have to worry very much at all about potato skins in pubs. Solanine tends to break down around temperatures above 300 F, and frying of potato skins and/or french fries tends to happen above 350 F, and it does a lot to reduce the toxicity because the crystalline structure falls apart and the toxin moves into the oil (and often also gets carried off in the vapor fumes). Boiling in water, otoh, does next to nothing, while baking or microwaving has some relatively small effect.
Also, unless you are deliberately seeking out potatoes which have an entirely green outer surface, the concentrations are low enough that you'd need to eat nearly 2 kg of potatoes in a single sitting to experience ill effects. In small doses, though, solanine is not poisonous and is actually slightly effective in managing asthma inflammation, though the effect that has shown more scientific verification is its pesticidal and fungicidal effects (which is also pretty much its primary purpose in the potato itself).
The commercially sold varieties are typically very low concentration, though if you are isolating the greened portions of potatoes, then you can reach somewhere around the LD50 dosage from a mass of green potato flesh roughly equal to the mass of a single russet potato. However, you'd have to be trying to kill yourself to do that. Of course, the eyes and sprouts are always troubling, but one problem with recommending always thoroughly peeling a potato is the fact that aside from the solanine, there is quite a large percentage of the nutrient value in those layers just beneath the skin.
There are a few varieties of potatoes being bred that do not produce chlorophyl under the condition of UV light exposure, So as to alloy for resistance to greening under UV lights in supermarkets. These varieties can contain High levels of solanine with little evidence in the form of chlorophyl. Chloryphyl is coincidental under UV exposure and not a direct indicator of solanine content. At least this is my understanding of it at this point. However I take your point about the deep frying although not having a direct control over the process I am still not a fan of consuming potato skins in the deep fried form.
Thankyou very much for the input though, do you have any other information on vegetables in relation to toxins and how to avoid them. For example the green foliage on tomato plants is toxic and I had always wondered about tomatoes and the green in the core....
Tomatoes have a related glycoalkaloid called tomatine. It also has antifungal and antimicrobial functions like solanine does, but it's a much more benign substance by comparison. The leaves and stems are simply where you find it in higher concentration and without any other substances that reduce its absorption rate. You'd have to consume quite a lot more to experience any ill effects. Also, there are strains of coliform bacteria in our digestive system which have tomatinases, so they can pretty much destroy tomatine quite easily (allowing us to absorb some extra sugars) without it having any antimicrobial effect within our digestive tract. We, unfortunately, don't have "solaninases", which if we did would erase any concerns about potatoes.
Although high quantities are still somewhat dangerous, you'd run into acidosis issues from consuming that much tomatoes long before the tomatine becomes poisonous. In lab conditions, though, you can use it to precipitate cholesterol out of solution, and it has been shown on some levels to stimulate immune response, so it does get used occasionally as an ingredient in vaccines... the effect of this is only likely to be dangerous if you already suffer from some severely acute autoimmune disorder (in which case, you wouldn't be eligible for most vaccines anyway).
That's about the limit of my knowledge. My fields of study are computer science and music theory, and I only know this much by virtue of my mother and my wife (the former being a botanist, the latter being a food chemist). Actually, my wife particularly likes to ramble a lot about potatoes in particular.
Thankyou very much for putting the concern about tomatoes in perspective. It is very interesting that we often disregard the natural pesticides and the like in our veg food source. Of particular interest are the observations that highly stressed plants usually produce much higher levels of toxins (and possibly antioxidants?), This is another possible motivation to grow ones own veg under controlled conditions....your thoughts?
That's definitely a factor. Another thing to look for as well is the kinds of stresses the plant has evolved to take. Potatoes have a more potent toxin than tomatoes partly because they just happen to have evolved to take on heavier stresses and survive under pretty poor conditions. Tomatoes aren't... and any attempt to grow them in poor conditions is either doomed to fail or will require massive degrees of augmentation.
You look, for instance, in Florida-grown tomatoes -- Florida is not really a good place for tomatoes (though you could grow potatoes there just fine). The reason tomato farmers even exist down there is because of the American demand to have fresh produce year-round rather than when it's in season. There's almost nothing you can do to eliminate stressing of the plant, so they have to just pile on the fertilizers and load up on compost and organic material and cycle through it over and over (almost 6x as much as growers in other states where they can only grow tomatoes in season), and because the sandy soil there causes a lot of runoff waste, it's extremely inefficient. In the end you will get a pretty substandard product that is picked when it's still green and rock hard and it's reddened in a plant using an ethylene-rich environment, but farmers aren't paid for quality, but for quantity. That pretty much applies to all commercial agriculture, and it also doesn't matter whether you're talking about hydroponically grown GMO grains or organically grown kohlrabi. Dollars and cents all comes down to weight.
As such, if you want to grow at home, you are likely to almost always put the plants under less stress than the average commercial farmer simply because you're working at a scale where it's much more feasible to keep conditions exceptionally well-managed. Just having sufficient topsoil is difficult for farmers, but not so much for a small personal home garden.
Very good points raised there, thank you.
I suppose in relation to genetics we have selected for productivity, appearance and marketability. The actual nutritional qualities if they are any good would just be coincidental, This makes me wonder if heirloom varieties vs modern strains may have undergone a nutritional study in recent times. We could just be eating the remnants of a formerly glorious fruit. That said one wonders about weather a selective criteria would have ever existed that suited nutritional value for humans, Either in agriculture or evolution. I mean, just because a tomato was selected for by a particular set of animal species may be of little relevance if the average nutritional makeup requirement for the set was way off that required by humans...Food for thought anyways...cheers
This makes me wonder if heirloom varieties vs modern strains may have undergone a nutritional study in recent times. We could just be eating the remnants of a formerly glorious fruit.
There actually has been -- and I think tomatoes are a somewhat more well-studied example. What I think a lot of larger-scale studies find is that there is some, but comparatively little difference between heirloom and modern tomatoes based on variety alone, but there is huge difference based on the growing conditions and farming practices, and some varieties respond to this a little more profoundly than others. i.e. Under crappy conditions, there is almost no difference between varieties... otoh, under very good conditions, a modern Beefsteak tomato will improve by some x, but say, an old-world Roma or an heirloom varietal might improve a good deal more. It so happens that as far as the market goes, there are hardly any heirloom varietal growers who grow in poor growing conditions, so the apparent difference when looking at the market available product is a bit skewed as its not quite apples to apples.
You might be interested in the book, Tomatoland by Barry Estabrook, which gets on this very point. It's one of those recent works in muckraking journalism which focuses a lot on tomato growers. It's a bit on the sensationalist end of the spectrum, but I wouldn't call it purely yellow. There is quite a lot on the nutrition and how almost every mineral in the majority of supermarket tomatoes has gone down (except for sodium). Something I wasn't quite expecting to find, though, was about the cruel labor practices in the field and that there's actually been quite a death toll of undocumented workers in tomato fields in the United States. The sad thing is that there were several cases of such workers getting sick because people would spray pesticides without properly notifying workers (so they failed to evacuate before spraying) -- and though they would merely get sick from one or two such incidences, because of their poverty, they would have to continue working... it so happens that if that occurred, it was often preferable for the farmers to let such errors carry on their course until the worker died because paying out a wrongful death settlement is cheaper than being held legally liable for someone's medical problems.
I'd also be interested to see how GMO crops have changed the landscape. Most of these have been modified for the express purpose of improving the output of very specific nutrients while at the same time being resistant to certain blights and pests and so on. There have been large scale studies on this, but I'm only aware of ones that pertain to grain crops used for livestock feed and industrial uses rather than food meant for human consumption.
Some very good points in there. The pesticide issue is one of the main reasons I am interested in "Organic", this said I rarely can afford them and am currently doing what I can to grow my own tomatoes. I have not to date been very happy with my results and had wondered what varieties to try next. I am thinking of building a hydroponic setup for the tomatoes and build a small portable greenhouse in order to facilitate
more experimentation in somewhat more controlled conditions. I am very glad to hear that from what you have seen we have not lost to much nutrition potential provided we take control of the growing conditions.
In relation to GMO, I think monsanto has "laid the seed's " for the demonisation of GM tech. Unfortunately now people paint the entire GM option as "bad", My intuition on this is that if we have the potential to cautiously improve our nutrition/footprint potential then it is an avenue we should peruse scientifically with desired outcome of a more sustainable world. However it would seem that in a capitalist world this outcome is not the mandate instead it is shareholder returns. Due to this scenario we see a technology used by a monopoly to create a plant that is able to resist a very harsh pesticide that they also happen to produce. I think we could make much greater inroads if we had socialised farming and agriculture technology R&D. Maybe we will get to that point one day. As for myself I will continue to do my best to feed myself and my wife off grid!!...lol. One good thing about being vegan and gluten free (celiac) is that there is so little food we can buy processed that its a lot easier to provide for yourself even on a small plot of land or even in pots. However I to am an avid computer/electronics Geek and really wan't to have a very advance greenhouse solution one day soon....cheers.
Kind regards VeganApe