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Protein Degradation in Water

I thought I read somewhere a long time ago that whey protein degrades shortly after mixing with water. Is this true.

What about casien. I assume not based on the structure.

[quote]mertdawg wrote:
I thought I read somewhere a long time ago that whey protein degrades shortly after mixing with water. Is this true.[/quote]

No. Heat can denature protein, water alone can not.

Hmmm I don’t know about that professor. Heat definietly denatures the protein(crosslinkage), no argument there. However take a scoop of protein powder put it a shaker and leave it for two days. Now go back, open that shaker–smells fine. Now take a scoop of protein powder and mix it with some water and leave it for two days. Now go back and as soon as you twist off the lid you will be attacked by the smell of rotting ass and protein funk. There has to be some kind of denaturing going on!

Wouldn’t that degradation be caused by bacteria in the water, rather than the water itself?

If I remember correctly, what I actually read was that whey protein, and specifically glutamine end up degrading to produce some ammonia when in water for several hours. Bad because ammonia makes you weaker instantly. It obviously can’t happen in 60-90 minutes that much or it would happen in your stomach.

Okay, lets think about this one.

What types of protein does milk have in it? How long does it sit around before going bad? When it goes bad, is it because the protein is mixed in water? Why do we keep it and other foods in the fridge?

Rotting and fermenting are the result of biological processes, not spontaneous protein devolution.

Otherwise, our muscles would be in big time peril considering they are flooded with water all day long.

My educated guess is that since the outside of proteins are hydrophillic, while the insides are hydrophobic, the protein shouldn’t be broken down by water. I believe ther are only three things that can denature a protein: heat, chaotropic agents (e.g. urea, guanidinium salts), and detergents. I agree that the ‘funk’ that is smelled is definately bacteria, probably untilizing the glucose and whatnot in the protein mix. What was the aim of the original question anyway?
I usually drink my protein shakes within 30 seconds of mixing them?

I’m doing a little research. I’m not talking about denaturing here btw. In water, Glutamine is in equilibrium with gluatamate and ammonia

Glutamine<---->Glutamate + Ammonia

Although based on the in vivo examples, it can’t be far to the right. It would seem that having extra glutamate would be good for pushing the equilibrium the other way.

Correct me if I’m wrong, but are single amino acids hydrophilic on the outside and hydrophobic on the outside? Glutamate and ammonia should both be very water soluble because of their polarity right?

Read the Think Tank dialog called “Quickie for JB & Lonman”. They address the stability of Surge which, as you know, contains protein.

[quote]mertdawg wrote:
If I remember correctly, what I actually read was that whey protein, and specifically glutamine end up degrading to produce some ammonia when in water for several hours. Bad because ammonia makes you weaker instantly. It obviously can’t happen in 60-90 minutes that much or it would happen in your stomach.[/quote]

60-90 min is not “shortly after mixing” and any breakdown would be the result of bacteria, not water. That is what refrigerators are for.

So Here’s My Real Question. I’ve got a couple of buckets of whey protein. I wanted to blend about 5 pounds of cottage cheese with about 10 scoops of whey protein, the idea being that the slow digesting cottage cheese protein would act as a kind of trap and release the whey nice and slow. I actually heard that whey protein starts to have a catabolic effect after 2-3 hours because it triggers a lowering in blood amino acid levels, unless you eat again. I thought it would be an overall long acting form of whey that could be used before bedtime. Can I mix this up, keep it in the refrigerator and use it over a 2-3 day period?
What do you think?

Every morning I mix up a power shake with berries, protein powder, milk, etc. Put it my insulated lunch bag with some Lunch-Pak refreezable ice blocks. Enjoy about 4pm, 7 hours later. Tastes great, no problem.

[quote]mertdawg wrote:
Can I mix this up, keep it in the refrigerator and use it over a 2-3 day period?
What do you think? [/quote]

I think there is nothing wrong with thinking of using casein as a longer acting supplement, however, there is no way I would mix a protein shake for 3 days from now, especially if CHEESE was in it.

no fancy chemistry folks just oxidation.

oxygen is the universal destroyer. as i type this it’s destroying your gto and your protein powder with equal force. even your dry, opened cans of grow! are going stale. water is merely a catylyst in this reaction. heat too.

oxidize, spoil, stale, degrade, destroy…all the same in this conversation. it’s just food and we’re simply racing to get ours before the elemental dogs get theirs.

if you need to pre-mix a shake for later consumption, put it into a glass screw cap bottle and fill it all the way to the top. keep it cold… gotta keep out the 02… gotta slow down mr.O… gotta eat before he does… oh and don’t use plastic. all kinds of nasty shit leaches out with every use… oxygen you know.