Glutamine is the amino acid in its free-form, which means it's in its whole food state, whenever you eat foods such as almonds and peanuts your ingesting glutamine amino acids. L-Glutamine is basically the same thing. Its glutamine in its free-form (whole food). The majority of supplement companies sell L-glutamine and tout it as the best form, which it is not.
Glutamic Acid is familiar if one turns over their container of protein powder and sees "glutamic acid". Why not glutamine instead of glutamic acid? "The reason is that the acid hydrolysis stage of the analysis converts the glutamine into glutamic acid, releasing ammonia. Thus the glutamic acid level actually represents the combined levels of glutamine and glutamic acid." (ref). One can figure out the amount of glutamine in the glutamic acid content fairly easy. In animal proteins such as whey, casein, milk, and egg proteins 50% is actually glutamine. In plant proteins such as soy, 80% is glutamine.

Glutamine Peptides in Layman's Terms
To understand the differences in glutamine peptides and regular glutamine, one must first obtain the knowledge of exactly what are peptides and how they are different from free form amino acids. Peptides are amino acids broken down into their smaller more digestible form using the hydrolyzation process. Only hydrolyzation can produce the smaller peptides, superior to free form amino acids and larger peptides currently found in your whey proteins that are produced NOT using the hydrolyzation method. The supplement companies make it sound difficult because there is a small amount of peptides that occur naturally, regularly commercially produced whole-protein supplements. Unfortunately, what the don't tell you is that these are the larger peptides with a high molecular weight, which is different from smaller di and tri peptides that are produced using the hydrolyzation method.
Several studies have shown that smaller peptides are better absorbed than larger peptides and regularly manufactured protein.
1. Amino acids from peptides are more readily absorbed than free-form amino acids, thus producing a greater insulin reaction.
2. Humans fed smaller peptides compared to whole-protein foods had a greater increase in amino acid levels.
3. Hydrolysated products produce greater pharmacological effects (increasing GH and insulin response).
4. OLIGOPEPTIDES are LARGER PEPTIDES, which are absorbed much SLOWER than small tri and di peptides. Supplement companies try to use the word "oligopeptides" to fool the customer with scientific mumbo-jumbo when they're actually stabbing themselves in the back!

Thus now our customers can see, why the Protein Factory choose Glutamine peptides instead of free-form L-Glutamine. You will get a better response with glutamine peptides when compared to L-Glutamine.

anyways thanks for the responses