I tend to go for an isolate during the day,two shakes if possible. After the gym and just before bed, I slam casein protien for the slow absorbing protien.

I have copied this post from: http://forum.bodybuilding.com/showthread.php?t=694992&page=43
This guy really knows what he's talking about, and I can tell this because he references Dr. Blaylock, who is the preeminent researcher into the varying forms of excitotoxins, including the excitotoxins in processed protein. I quote from here to end:

First off, the VAST majority of so-called casein supplements on the market are comprised not of casein, but an overly processed variant of casein called calcium caseinate.

Calcium Caseinate IS NOT Casein

The production of caseinate protein begins with skim milk which has been pasteurized at 72 C (162 F) for 15 ? 20 seconds. This starting material is similar to what you would find in skim milk from your grocery store for example.

When you read about all of the additional processing which this milk undergoes to make caseinate powders, you should ask yourself if there are any harmful changes that take place when protein goes from fresh milk to a powder sitting on a shelf at your local supplement store. There?s a lot of wishful thinking in the food processing industry, and they?d like you to believe that their processed foods are as safe and nutritious as whole fresh foods. But when you know how these products are made, you may come to different conclusions.

So, this skim milk is first processed with acid (usually hydrochloric acid) to coagulate and separate the casein protein from the watery whey.

Then this ?acid casein? as it is called, is washed and often dried. By this time in the production, protein denaturation has already begun.

Then, this casein is reacted with more chemical reagents (alkali, not acids this time) to produce mineral caseinates. Sodium caseinate is made by reating acid casein with sodium hydroxide (or lye), and calcium caseinate is made by reacting acid casein with calcium hydroxide (or lime).

In buffering the acid casein, these potentially harsh chemicals can cause even more of the protein to become denatured, transforming them into potentially toxic compounds.

Studies regarding the effects of alkali-treated proteins:

http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum

http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum

The product is then spray-dried into powders and sold in many nutritional supplements as calcium or sodium caseinate.

So, the supplement industry wants you to believe that casein and caseinates are the same thing, but after being washed, dryed, and treated with harsh chemicals, powdered caseinate supplements stand little chance of offering the same nutrition as the casein from milk, or cheese.

-Caseinates and Free Glutamate-

As an example of the effect of processing on casein, Dr. Russell Blaylock M.D., in his book Excitotoxins The Taste that Kills, lists calcium and sodium caseinates as food additives which ALWAYS contain free glutamate.

Free glutamate (glutamate separated from protein) is a known excitotoxin, and can be toxic to the neurons of the brain, and the entire nervous system. It is free glutamate which makes the infamous food additive MSG (or monosodium glutamate) so dangerous.

Casein is one of nature?s richest sources of glutamate, but the relatively stable and slow digesting casein micelle (curd) probably protects us from glutamate-induced neuronal damage if we eat milk and cheese based FOODS.

On the other hand, harsh acid and alkali processing in the production of calcium and sodium caseinate powders likely denatures the casein, freeing up glutamate in the process, a phenomenon that would NOT take place in minimally processed milk or cheese.

As a side note, it is possible to produce a non-denatured casein powder, but very few supplement companies would use such an ingredient because of its high price.

I can?t stress enough: READ THE INGREDIENTS on your supplements. A product that is advertised as ?Casein? will usually contain minimal amounts (if any) undenatured casein, and large amounts of the cheaper caseinates.

Where have we heard this story before? Why, with whey, of course. Companies often use high amounts of the cheaper whey protein concentrate, with absolutely miniscule amounts (if any) of quality whey protein isolate in their products.

Are you starting to see a trend here?

The bottom line is that most supplement companies pray that you don?t know what the heck you?re putting in your body. If you knew what they were trying to sell you, how it was made and what it really does, you?d have no part of it.

As it stands now, however, many supplement companies still rely on consumer ignorance to be able to sell the cheapest ingredients at inflated prices.

The whole issue of fast versus slow proteins has been completely blown out of proportion by the supplement industry to sell you more processed powders. The fact is that any ?real food? source of protein will digest slowly enough to supply a sustained release of amino acids into the body over a longer period of time. If a supplement company doesn?t tell you this, chances are they?re trying to sell you a cheap caseinate powder, which is a very poor replacement for real food.

Not only should low quality caseinate powders be avoided, but casein and caseinates don?t need to be supplemented in the first place. If you want casein, there are too many other real foods that are much better sources of it.

Casein is hands down the most unhealthy protein. It is cow milk protein, which is meant to create a 600 lb cow from a calf in less than a year. Humans are the only animal on the planet which willingly drink other species milk, and it is very bad for you. It is very hard for the body to break down and assimilate casein. Long term use of this will wear out the vital energy of the body, causing pre-mature aging, debility, and cancer. Milk protein is especially dangerous now due to the fact that the cows are fed GMO grains. Look up GMO's on naturalnews.com or on this search engine: ixquick.com In general, if you want to be healthy, stay away from dairy, and that includes whey. I opt for hemp protein powder.

Best advise dont over complicate it. I use isolate for everything. An evening meal high in protein will far surpass any shake.

Casein for slow absorption throughout the night. Or low fat cottage cheese and a glass of low fat milk will do the trick and probably cheaper. Whey first thing am and after training.

Best to go with casein in the evening and isolate after training if it fits in your budget, they tend to be two of the more expensive proteins. whey spikes insulin more than casein and you dont want to spike your insulin before going to bed. if its cost prohibitive id go with a blend at both those times.

Casein. Unless I trained that evening.

i blend cottage cheese with whey protein before bed