Dextrin

[Kdogg]

Im wondering if any of you know a good procedure for making dextrin. Im looking forward to trying out some black match.

This is a Recipe I found on google, I was wondering if it was accurate:
"You'll need some common Corn Flour (or Corn Starch) from the supermarket. Spread this out in a thin (1/2 inch thick) layer on a baking tray. Place this in the oven for about 4 to 6 hours on a high setting, 220 to 240 degrees Celcius. You will know when the starch has been converted to Dextrin, because it will have turned a darker colour, golden brown. "

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Monkeyman

[kingspaz]

isn't that from J's website?
yes it works. i haven't tried it for the 6 hours. i think that temps a bit high though...when i tried it for an hour i had to turn it down to about 185*C because it started smokin. also i've read 182*C is correct temp but it could be my brain playing up again...

[Donutty]

Isn't corn flour completely different from corn starch?? I'd imagine that corn flour is as is says (but isn't all flour made from some type of corn?? - or maybe this is corn like popping corn) and that corn starch is the starch from this flour. I think they could be completely different things.

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...AAGH! It Burns!...

[kingspaz]

drop some idodine solution onto flour. it turns blue/black. starch is present. flour is mostly starch but corn flour is pure starch. mine says on the side its ground maize starch. i only recently realised that when people talk about corn starch they mean corn flour...or maybe they don't...well even if i was wrong that still lead me to finding out corn flour is starch.

[Kdogg]

kingspaz IS RIGHT!!!! That temp was way to high. I started it in a pizza frier, & Checked on it about every 5 minutes for a hour or so, it looked exactly the same everytime I checked. Then that last time I checked it looked the same also, so I left it sit another 5 minutes, Before I knew it the whole house was filled with smoke & the shit was on fire. I had it going in my room near a door. So I just unplugged it & took it outside. Luckily it didnt ruin the frier, but all my starch went from a 1/2 inch pile of soft white powder to a huge 6 inch black mound of soot shit.

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Monkeyman

[MacCleod]

Corn flour and corn starch are indeed different,corn flour being finely ground corn (not to be confused with white flour,which is ground bleached wheat).

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"That which does not kill us,makes us stronger"

[cutefix]

I realize, that for an Englishman the cornflour is synonymous to American cornstarch.I did experience this predicament when I was working with a British colleague in an overseas job …..Indeed there was an argument about it,and unfortunately there was no sample of both products for comparison,and was only sorted out using carbohydrate chemistry,as well as how its materials is obtained from the grain.If you will notice, cornflour appears granular and feels somewhatgritty while cornstarch looks very fine and smooth to touch.

Cornstarch can be converted to maximum quantities to dextrin than cornflour which contains aside form starch; non starch polysaccharides cellulosic materials like pentosans,hemicellulose etc.)

[kingspaz]

right, i've made some heres what i did:
put corn flour on a metal tray
spread it out as thin as possible
left it in the oven at 185*C for about 1 1/2 hours
thats it! it will look just the same afterwards apart from a kinda golden tinge to it.

[Donutty]

Isn't that just toasted corn flour then? http://theforum.virtualave.net/ubb/smilies/smile.gif

Where can you buy dextrin? Is it used for food products in any way? I know you can order it from pyro companies, but surely there is another use for it...

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...AAGH! It Burns!...

[kingspaz]

i bet they use it in sticky sweets. its not worth buying though considering how easily made it is. i think i've seen it on food ingredients before...HARIBO! i think it may be in those. (emphasis on think!)

[Donutty]

OK, I admit defeat. This is taken directly from the packet of Corn Flour I just bought:

"Brown & Polson Original Patent Cornflour is pure fine white corn starch milled from maize grain from which the outer hull, germ and gluten have been removed by a patented milling process"

So, Cornflour = Corn Starch!!

Glad we settled that one...

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...AAGH! It Burns!...

[Gab]

If you mix corn starch with water, you will get a half-liquid half-solid goo. You can dip things in it or pour it in another container but if you punch it with your fist, it be solid and your fist won't go into it all and none will splatters.

[CodeMason]

From Dick's Encyclopedia:
4345. Dextrine or Starch Gum
Heat 4 gallons watter in a water-bath to between 77° and 86° Fahr.; stir in 1 1/2 or 2 pounds finely ground malt; raise the temperature to 140°, add 10 pounds potato or other starch; mix all thoroughly, raise the heat to 158° and keep it between that and 167° for 20 or 30 minutes. When the liquor becomes thin, instantly raise the heat to the boiling point, to prevent the formation of sugar. Strain the liquor, and evaporate it to dryness, as the dextrine will not keep long in a liquid form. Another method is to boil solution of starch with a few drops of sulphuric acid, filter the solution, and add alcohol to throw down the dextrine.
Or: Mix 500 parts potato starch with 1500 parts of cold distilled water and 8 parts of pure oxalic acid; place this mixture in a suitable vessel on a water-bath, and heat until a small sample tested with iodine solution does not produce the reaction of starch. When this is found to be the case, immediately remove the vessel from the water-bath, and neutralize the liquid with pure carbonate of lime. After having been left standing for a couple of days the liquor is filtered, and the clear filtrate evaporated upon a water-bath until the mass has become quite a paste, which is removed by a spatula, and, having been made into a thin cake, is placed upon paper and further dried in a warm place; 220 parts of pure dextrine are thus obtained.

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[mark]

If your making blackmatch forget about dextrin. Use ruber cement. I know it sounds kewl, but it realy is the superior binder. It holds the black powder very well, and the fuse is very flexible. None of the powder cracks of when bent.