Quicksand Fans

Was checking up on youtube for some late night videos, and found this on the front page. Now, I'm no science guy, but that magic mud he has looks a lot like cornstarch, albeit glow it's glowing in the dark. https://youtu.be/_0J4dRqg7CE

I think I've seen that and yes, it's fascinating and looks amazing! But I wonder how much of that magic mud you get per bag of potatoes? Doesn't look like a great deal,and does it go off or rot after a while?

Considering potatoes contain a large amount of starch, I suppose this is the key substance in both the magic mud and cornstarch (or as we call it over here, cornflour) ?

tanya_wam wrote:I think I've seen that and yes, it's fascinating and looks amazing! But I wonder how much of that magic mud you get per bag of potatoes? Doesn't look like a great deal,and does it go off or rot after a while?

Considering potatoes contain a large amount of starch, I suppose this is the key substance in both the magic mud and cornstarch (or as we call it over here, cornflour) ?

Cornstarch is obtained from,.... err.,,,, corn. But you are correct that any kind of starch can be used to make oobleck.

Fred588 wrote:

tanya_wam wrote:I think I've seen that and yes, it's fascinating and looks amazing! But I wonder how much of that magic mud you get per bag of potatoes? Doesn't look like a great deal,and does it go off or rot after a while?

Considering potatoes contain a large amount of starch, I suppose this is the key substance in both the magic mud and cornstarch (or as we call it over here, cornflour) ?

Cornstarch is obtained from,.... err.,,,, corn. But you are correct that any kind of starch can be used to make oobleck.

Didn't I say starch, as opposed to just cornstarch?

To increase the efficiency of the process, the potatoes would have to be more finely ground up before being mixed with water, and then finally put through some sort of press to extract as much starchy juice as possible. Then, the mixing with water and pressing could be repeated a few times to collect what was missed from the previous time(s).

Boggy Man wrote:To increase the efficiency of the process, the potatoes would have to be more finely ground up before being mixed with water, and then finally put through some sort of press to extract as much starchy juice as possible. Then, the mixing with water and pressing could be repeated a few times to collect what was missed from the previous time(s).

Would it quick and cheaper to just purchase starch? Or is it not quite the same as cornstarch or potato starch?

tanya_wam wrote:

Boggy Man wrote:To increase the efficiency of the process, the potatoes would have to be more finely ground up before being mixed with water, and then finally put through some sort of press to extract as much starchy juice as possible. Then, the mixing with water and pressing could be repeated a few times to collect what was missed from the previous time(s).

Would it quick and cheaper to just purchase starch? Or is it not quite the same as cornstarch or potato starch?

I have not priced it but I'd expect corn starch to be both cheaper and easier to obtain, at least in the USA. In places where, say, corn is not grown in quantity but potatoes are, that might change I suppose.

Fred588 wrote:I have not priced it but I'd expect corn starch to be both cheaper and easier to obtain, at least in the USA. In places where, say, corn is not grown in quantity but potatoes are, that might change I suppose.

You are totally right. As soon as I've seen first videos with non-Newtonian liquids, I was wondering what that magic thing named "cornstarch" is. In my part of the world it is totally unknown. Any kids (at least those ones that listen to their teachers in school) know that starch is extracted from potatoes.

I never had starch in volumes larger than a small bucket (it was commonly used to stick wallpapers on walls - and I believe many kinds of wallpaper glue that we purchase in stores now are also based on starch). But I have to admit that:

• Cornstarch-water mixture that I see in videos is opaque and white, while solute potato starch is colorless and transparent.
• I have never noticed any substantial thixotropy of solute potato starch - it is just a thick, viscous, sticky liquid. Though I never did any special experiments, to say the truth...

If someone not very competent would be interested in extracting starch from potatoes, I have to mention one thing. High concentration of starch exist in potatoes harvested in autumn. In my country it is the major part of potatoes. But when I was abroad (e.g., in Germany), I noticed that most of potatoes that people can buy in supermarkets is "young potato", which in my country is available since June but not after July. It is healthier for food but it contains much less starch (actually, this is the main reason why it is healthier). So, not any potato is suitable for extracting the starch.

Late in the season, when potatoes are harvested, I must imagine there could be a number of culls thrown out that could be utilized. Of course, since it would be late in the season, the starch would have to be dried and saved for the following year. However, the amount of work needed to acquire enough starch to sink deep into could be a bit daunting, to say the least.