new research debunks trad views on nutrition

[Sally PB]

But again, my knowledge of clay is mostly cuss words...

Yup, same here. Soup line, clay, soup line.*

* my home made, clean version of a cuss word.

 

[RoyalChick]

actually, does anyone know any way in which beef fat would be used in the manufacture of ceramics? I rather suspect some confusion with animal fats being absorbed by some (notably, ancient) ceramics, so archaeologists can tell something about what the people who made the pot cooked or ate in it (but nothing to do with making the pot).

Well in ancient times maybe to seal the surface to make something waterproof so it could hold liquid? Probably done with wood as well.
My mother was a potter and she experimented with glazes - I can imagine maybe animal fat could be mixed in a glaze, but I have no idea really.

 

[saysfaa]

This says "meat and bone meal" is used to make building industry ceramics by burning the meat and bone meal to ash then using certain parts of the ash (bottom ash not fly ash) instead of the sand that was typically used. The plasticity of the forming mass, drying and firing shrinkage as well as density of ceramic body changed insignificantly whereas the compressive strength increased by 8 % - 22 %.

It looks like testing the application rather than production but I didn't see a date.

It also doesn't say fat, but it seems likely that the "meat" of the "meat and bone meal" is quite fatty.

Edit to add: oh, 2011
But there are lots of references. Some from years earlier, although the ceramics for other applications.

Wikipedia says it is typically 8-12% fat; better sources say MBM is what is left after the fat is rendered out. I trust the other sources more so no longer think there is much fat in it. Or not. Another source about parts of the MBM ash used to make ceramics says MBM is "crushed bones and meat" straight from slaughterhouses. There seems to be multiple definitions.

Some sources talk about the differences in the properties of the ceramics from the different additives to the clays that make the ceramics - bone alone, MBM, others... I haven't found fat alone yet.

 

[Perris]

Well in ancient times maybe to seal the surface to make something waterproof so it could hold liquid?

so a temporary modification rather than the manufacture of it per se? I too can imagine that (though I still think it would not qualify it for inclusion in that poster)

Probably done with wood as well.

if memory serves correct, one of the hypotheses to explain the origin of pottery per se is that clay was used as a liner to make baskets waterproof; add fire (accidentally) and the basket burns away and, if lucky, one is left with a solid pot (though not a waterproof one in that case Got a lot more steps to pass to get to a waterproof pottery bowl ). So using fat to waterproof a porous clay bowl would fit nicely into that sort of scenario.

I can imagine maybe animal fat could be mixed in a glaze

I'm not sure about that. My understanding is that glazes are tricky and it's easier to adjust the body of the clay to suit the glaze (they have to bind together in firing conditions that suit both of them) than the glaze to suit the clay, so glaze compositions are more conservative than clay bodies. I'll have a rummage in the library and see what I can find. Got some books on clay and ceramics somewhere.

 

[Mrs. K]

The thing is, if you are commercially creating eggs, you want to do it on the least food possible without decreasing egg production which will decline on poorly kept birds. Food is expensive.

So you want a pretty consistent feed that meets needs, that chickens will eat and produce eggs.

 

[Perris]

It looks like testing the application rather than production but I didn't see a date.

it's motivated by trying to find a use for meat bones post BSE regulations, so the article linked at least isn't about historic use but may be inspired by historic production of bone china. I'm sure bones were calcined for that, so there wouldn't be any fat left by the time it met any clay.

 

[Perris]

The thing is, if you are commercially creating eggs, you want to do it on the least food possible without decreasing egg production which will decline on poorly kept birds. Food is expensive.

So you want a pretty consistent feed that meets needs, that chickens will eat and produce eggs.

I think you meant to post this somewhere else

 

[Perris]

or maybe not? Is it a propos anything in particular in earlier posts on this thread?

 

[Perris]

I'll have a rummage in the library and see what I can find. Got some books on clay and ceramics somewhere.

Of course it is impossible to find something if it is not there, and so far I have drawn a blank. Clays and glazes are inorganic mineral substances; their additives are also. I find no trace of deliberate fat inclusion in anything I've looked at so far. I think the poster is just wrong in that respect (amongst others, like the bone byproducts; to which obvious adds are e.g. knucklebones, dice, and other game pieces - which are still made I find, though not nearly to the same quality as in times past https://scape-west.co.uk/shop/accessories/hand-carved-buffalo-bone-horn-chess-set/ ). And the bone (ash) in glass appears to be an error too; bone ash was used as a separator in mould-made objects, to facilitate removal from the mould, and sometimes stuck to the hot glass.

 

[Perris]

Tax for a lot of irrelevance: Hensol filling out nicely