baking powder...


by BlackCatXIII
Tags: baking, powder
BlackCatXIII
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#1
Mar5-04, 02:24 AM
P: 4
some types of baking powder consist of sodium bicarbonate, NaHCO3, and calcium dihydrogen phosphate, Ca(H2PO4)2.
Can anyone explain the function of the Ca(H2PO4)2 in the baking powder????
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thunderfvck
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#2
Mar6-04, 02:59 AM
P: 210
I'm not sure but I'll speculate.

Maybe the H2PO4 acts as the acid in the baking powder, and reacts with the NaHCO3 to make the CO2 that expands the bread or cookies or whatever?

I don't even know what they use the baking powder for, so...

Edit:
I did some testing. I put some baking powder in a beaker, added some water, nothing happened. I then heated the water. Bubbles began to form, the gas produced put out the flame from my lighter. Although I can't tell you whether or not it was simply water boiling, because I don't have a thermometer, but I'm pretty sure the water wasn't 100C.

So, what I think happened was the heat was sufficient to break the bond between Ca and H2PO4, the H2PO4 then reacted with the NaHCO3 and created CO2 gas. THis gas is used to expand breads and all the other goodies. Am I the man, or what? Damn I feel smart. Like I deserve a nobel prize or something. HAHA.

I have some questions though. Why does this require heat? It'd be pretty impratical to have it bubbling at room temperature, I know. But should the Ca(H2PO4)2 immediately split in solution, as it's an ionic bond? Or is it that the water molecules aren't strong enough to rip the two apart, so it needs a little heat?
Monique
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#3
Mar6-04, 03:52 AM
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You don't require heat when baking, you require a slightly acidic environment. That then breakes down the baking soda (NaHCO3), with the production of CO2 gas, which expands the bread. The Ca(H2PO4)2 would be the acid. In how much volume did you dissolve the baking powder, thunderfvck? Try the experiment again and just add some acidic acid.

You could also use yeast, which start fermenting and produce CO2. For them you dó need a warm environment, for them to feel happy :)

Monique
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#4
Mar6-04, 04:12 AM
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baking powder...


I just thought of something: were you using single acting or double acting baking powder? Double acting releases bubbles again when it gets hot..
thunderfvck
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#5
Mar6-04, 04:16 AM
P: 210
acetic acid

I'm not sure I understand the point you're trying to prove. Sorry, it IS 5 am...

Yes, Ca(H2PO4)2 is the acid, well, the acid would REALLY be the H2PO4- ion but now I'm being picky...And yes, adding acetic acid would decompose the NaHCO3 to H2O, CO2, sodium acetate. Why would you want me to add acetic acid? What would this prove? But I'm saying, the purpose of having the Ca(H2PO4)2 in the baking powder, in addition to the NaHCO3 is so that when thw two are together, and the H2PO4- ion is liberated, it reacts with the NaHCO3 to produce the CO2.

And you don't require heat when baking?

...

I'm sorry Monique. You are incredibly hot but I just don't understand much of your reply. Maybe it's because your imcomprehendible beauty is blinding my attmept to understand what it is you're trying to tell me. Please, do us all a favour and remove that picture. It's a dirty trick you're playing. [6)] [6)] [6)]

Single acting or double acting? It doesn't say. Oh and I used about 5 ml's of water, but I don't see how that makes a difference...
Monique
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#6
Mar6-04, 04:17 AM
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.. but then it would have required a slow acid like sodium aluminum sulfate..
thunderfvck
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#7
Mar6-04, 04:21 AM
P: 210
What?

Are you replying to me or just continuing what you've said from before?
Monique
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#8
Mar6-04, 04:22 AM
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I asked in how much volume you were dissolving your baking powder. You might have diluted the acid too much, so that it won't react with the soda anymore. That's why I suggested adding some acid to get some CO2 production :)

And oh, the sodium aluminum sulfate would be an acid which would work better when some heat is added to the reaction, the second acting agent. The first acting acid would be one that is stronger, such as the H2PO4-
thunderfvck
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#9
Mar6-04, 04:28 AM
P: 210
I should have also mentioned that initially I had dropped some of the baking powder in my sink, added a drop of water to it, and saw nothing. No bubbles.

And I really don't think dillution would be a problem here?
I mean, if there's acid in there, it will react with the NaHCO3. Besides, I used quite a bit of powder.

The heat just probably speeds up the process.

And what would be the point of adding acid if the whole point was to test if the baking powder was able to produce by its own means CO2?
Monique
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#10
Mar6-04, 04:30 AM
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http://users.rcn.com/sue.interport/food/bakgsoda.html
Single-acting baking powders are characterized by the type of acid they include. Tartrate baking powders contain both cream of tartar (potassium acid tartrate) and tartaric acid. These create gas quickly when combined with baking soda in the presence of liquid, so the batter must be cooked quickly or it will go flat. Phosphate baking powders contain either calcium phosphate or disodium pyrophosphate (source of sodium pyrophosphate). They work a little slower than the tartrate baking powders, but most of the gas is still created outside of the oven and therefore can be lost. S.A.S. baking powders have sodium aluminum sulfate (alum) as the acid. S.A.S. baking powders react slowly at room temperature and release more of the gas when heated. The phosphate and tartrate baking powders react rapidly at room temperature to release the leavening gas, which means that the batter has to be cooked quickly after the liquid ingredients have been added. On the other hand, the S.A.S. baking powders are better for products that will sit a while before being cooked. The problem with S.A.S. powders is that they have a bitter taste. They are used in combination with other leavening agents so not as much is needed. S.A.S. is often used in D.A. powders.

Double-acting (D.A.) baking powders are the most common type of baking powder in US supermarkets. The first "action" refers to the release of gas when the baking soda in the powder reacts with an acidic liquid. D.A. baking powders contain a dry acid which does not react with the baking soda in the powder until water is added; at that point the baking soda dissolves, the acid dissolves, and the two can now mix and the reaction shown above occurs.

The second "action" refers to the release of gas when the batter is heated in the oven or on a griddle. This relies on the presence of the slower acting acid, S.A.S. which only combines with soda when the temperature increases.
Some experiments: http://users.rcn.com/sue.interport/food/sodaexpt.html
thunderfvck
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#11
Mar6-04, 04:39 AM
P: 210
Ah. Very nice. My baking powder doesn't contain the sodium aluminum sulphate. Look, I'm quite tired and can't think very well. I skimmed those links you provided but didn't realy put much thought into it. More on this tomorrow!
goodnight monique, I'll see you in my dreams...[;)]






wet dreams?[6)]


AHAHAHAH
Monique
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#12
Mar6-04, 04:42 AM
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It's already noon over here, but anyway :) And you should work on your manners, you're not exactly acting like a gentleman.
thunderfvck
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#13
Mar6-04, 03:09 PM
P: 210
Well then! Very interesting. See what a bit of searching can do? FInd all your answers! And then you don't even have to ask these questions, although it's nice, you know. It gives me the chance to learn something new.

And Monique, I am sorry for being so rude. I get that way late at night. It's kind of like the werewolf syndrome, you know...full moon, hairy palms...Same kind of deal. Only for me it's late at night. hah. And it will reassure you that I did not have any dreams about you! hahah. I dreamed that I was in this video game...and I had to escape the town without being seen by any of these other guys, they all saw me but none of them brought me back to the dungeon master. It was quite fortunate. The dungeon master was quite frightening as I recall. There were other details but I'll spare you the boredom.
Monique
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#14
Mar6-04, 04:21 PM
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Originally posted by thunderfvck
And Monique, I am sorry for being so rude.
This might be the internet, but that doesn't mean rules of etiquette don't apply to it [;)]
thanks though :)


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