Guest guest Posted February 2, 2004 Report Share Posted February 2, 2004 Chris- >Soaking a >bone in an acidic solution, such as vinegar, dissolves its mineral salts, >causing the bone to become rubbery and flexible. " Yes, but vinegar is hugely more acidic than broth. When we make broth, we add a little vinegar -- or wine, which isn't even as acidic as vinegar. And when we make broth (or at least when I make broth) bones come out crumbly and kind of honeycombed-looking, not rubbery and flexible. Look, I'm not disputing that our stocks have more calcium than regular ones -- probably much more. I'm just suggesting that we're not transferring minerals from the bones we use to the stock en masse like some people sometimes suggest we are. - Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2004 Report Share Posted February 3, 2004 , > >Soaking a > >bone in an acidic solution, such as vinegar, dissolves its mineral salts, > >causing the bone to become rubbery and flexible. " > > Yes, but vinegar is hugely more acidic than broth. When we make broth, we > add a little vinegar -- or wine, which isn't even as acidic as > vinegar. And when we make broth (or at least when I make broth) bones come > out crumbly and kind of honeycombed-looking, not rubbery and flexible. I understand that, and, in fact, I bet adding two tbsp of vinegar to a gallon of water for chicken stock doesn't even change the pH much at all. The excerpt from the book wasn't meant to " prove " that that would occur, but was meant to illustrate the concept of how mineral salts are formed in bone, as a basis for my inability to understand how the collagen could dissolve and leave the mineral salts behind. It just doesn't make sense, the way the two are intertwined. Dissolving the mineral salts and leaving the collagen behind is much more likely, since the collagen is much bigger. > Look, I'm not disputing that our stocks have more calcium than regular ones > > -- probably much more. I'm just suggesting that we're not transferring > minerals from the bones we use to the stock en masse like some people > sometimes suggest we are. Perhaps not, but they must have a significant amount of calcium, and it seems much more likely that the associated Ca salts are dissolving with the collagen than not. The mineral salts are not associated in a giant crystal like a big rock, they are associated in microscopic crystals in the spaces between collagen. When the collagen is gone, are they just going to magically crystallize in place? If so, you would see a radical gemoetric restructuring of the bone and it would get much smaller. Instead what you see is the same-shaped, same-sized bone with a bunch of pits and holes in it. Anyway, we should be able to calculate it. It was difficult for me to figure out how to find the change in K with a change in T, because most of the formulas utilized some data point we didn't have. There are only two formulas that relate G or K to G *standard* (which is what the thermodynamic data charts give you), and one, delta G = delta G standard + RT lnQ requires you to know Q or K, which is what we're trying to find out. Anyway, if, later, I can find out how K changes with T, we should be able to make a reasonable guestimate how much CaCO3 and Ca(3)PO4(2) is going to dissociate into solution when boiling it. We can also figure how the pH affects this by determining the formation of HPO4, H2PO4, H3PO4, HCO3, and H2CO3, all of which would push the equilibrium for the dissociation of the respective compounds to the right. Again, I suspect the pH modification of the amount of acids recommended in NT is somewhat miniscule, but maybe that can shed some light on how we can rearrange the recipe to maximize Ca content of the broth. This would be a rather laborious calculation, but for various reasons, I don't mind it, as I'd like to keep my chem and math skills sharp, so I'll probably try to do it when I get home this evening. Chris Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2004 Report Share Posted February 3, 2004 Chris- >It just doesn't make sense, the way the two are >intertwined. Dissolving the mineral salts and leaving the collagen behind >is much >more likely, since the collagen is much bigger. Presumably collagen is much more soluble than calcium, but whether it makes sense or not, we're not getting rubbery bones, we're getting crumbly, brittle lumps of calcium. Presumably there's some collagen left, but from the texture of the bone remnants, I tend to think that we're sucking out more collagen than calcium. Anyway, if you find the time to do a calculation I'd be interested in the results. - Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2004 Report Share Posted February 3, 2004 In a message dated 2/3/04 5:22:39 PM Eastern Standard Time, michaelantonparker@... writes: > Bone size, strength considerations could totally throw the numbers > off I think. Consider as a thought experiment the case of taking a > bone and smashing it or grinding it using mechanical energy, not heat > energy, and then placing it in the stockpot. In the extreme case if > your grinding was fine enough then you get 100% Ca dissolution with > no relation to heat input! The calculation would be a rough estimate, hardly perfect, but would just give us a reasonable idea of what to expect. However, mechanically grinding the bone would do nothing to increase the solubility, which would be limited by the solubility equilibrium. Of course you need exposure, but the proteins that contribute to tensile strength and that hold the mineral salts in place are much more soluble than the salts themselves, and clearly dissolve into the water, so I dont' really see why that's an issue. Chris Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2004 Report Share Posted February 3, 2004 In a message dated 2/3/04 5:22:39 PM Eastern Standard Time, michaelantonparker@... writes: > But > please follow through with this wonderful exercise anyhow! There's > no doubt something good will come from it, at the very least a > wonderful clarification of the questions to ask! It would be > especially great to run your results past some senior expert in a > relevant field. Integrating various domains of sophisticated > knowledge like that is very impressive! (Heck, that's the kind of > stuff that'll get you into better phd/md programs!) Go for it! Thanks for the tip and the encouragement :-) I think I'm going to have to go to an expert just so I can find the appropriate thermodynamic data. It's almost impossible to find on the internet. I just realized that the data I have is the delta G of *formation*-- I was assuming I could just reverse the sign for the dissolution of the compound, but I just realized that formation doesn't mean formation from Ca and PO4, it means formation from each element in their naturally stable state, which includes the phosphate formation from phosphorus and diatomic oxygen. So I need to find the delta G for the actual dissociation reaction. I assume someone will have some sort of encyclopedia that has all these values. I'm doing independent study research into nanocrystals, and this week I have to review solubility, so on Friday I'll run this by my teacher, since its sort of on the subject. Chris Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2004 Report Share Posted February 3, 2004 @@@@@@@@@@@ > But we should be able to calculate how boiling would increase the solubility > equilibrium for calcium carbonate and calcium phosphate with > K=e^(-detaGstandard/RT) for T=373K (boiling) if one gets the standard change in free energy > from a selected thermodynamic data chart. @@@@@@@@@@@ Wouldn't you need to use surface area in your calculations? That would vary hugely for different animals and different types and shapes of bones... I mean otherwise you'd have numbers reflecting the solubility equilibrium for stuff that was in the middle of a chunk of bone even after the full heat treatment period, since we all know large bones don't *completely* fall apart, or even mostly fall apart. Maybe you could fudge with average diameter numbers for multiple cases. Bone size, strength considerations could totally throw the numbers off I think. Consider as a thought experiment the case of taking a bone and smashing it or grinding it using mechanical energy, not heat energy, and then placing it in the stockpot. In the extreme case if your grinding was fine enough then you get 100% Ca dissolution with no relation to heat input! My gut mathematical feeling is that things like this would skew your numbers so much that they wouldn't have any practical meaning. But please follow through with this wonderful exercise anyhow! There's no doubt something good will come from it, at the very least a wonderful clarification of the questions to ask! It would be especially great to run your results past some senior expert in a relevant field. Integrating various domains of sophisticated knowledge like that is very impressive! (Heck, that's the kind of stuff that'll get you into better phd/md programs!) Go for it! Mike SE Pennsylvania Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2004 Report Share Posted February 3, 2004 Mike- >In the extreme case if >your grinding was fine enough then you get 100% Ca dissolution with >no relation to heat input! Except it's even more complicated than that, because you'd almost certainly reach the saturation point long before you dissolved all that calcium in the water. I'd love to see Chris' calculations, but even so, as you say, they're almost certainly meaningless in any real-world sense due to the multiplicity of other variables that would need to be accounted for. - Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 4, 2004 Report Share Posted February 4, 2004 Hello everyone. I've decided to let , my son, age 2 1/2, try some raw goats milk in the form of yogurt and kefir. I'm a little concerned about this, however, because both sides of the family are lactose intolerant. I have read that many lactose intolerant people do better with yogurt/kefir, so I'm willing to try it. I want to replace the soy yogurt I have slowly phased out of his diet. He has so many picky issues that I feel a source of minerals and protein like goats milk would be a nice addition to his diet, seeing that he will probably stop breastfeeding within a year or so. I know lastase production decreases with age for many people, so I'm thinking I could just watch for any signs. Has anyone here been able to digest dairy after being lactose intolerant? What about your children? I know in Cuba and Trinidad( is Cuban/Italian/Trinidad/Guyanese) there was alot more goat milk being used, so I feel it would be a better animal. Also, I know the proteins are easier to digest. Any information regarding this subject would be greatly appreciated. Thank you, Michele _________________________________________________________________ There are now three new levels of MSN Hotmail Extra Storage! Learn more. http://join.msn.com/?pgmarket=en-us & page=hotmail/es2 & ST=1 Quote Link to comment Share on other sites More sharing options...
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