L-glutamine
L-glutamine is a non-essential amino acid that carries an amide group on its side chain. Commercial L-glutamine is made by bacterial fermentation of sugars, then purified by ion exchange and crystallized to a white powder. Brands buy it for powders, capsules and drink mixes; it is stable as a dry powder but breaks down in water over time to pyroglutamic acid and ammonia, which limits liquid formats.
Suppliers sell different products under the same name. Specify the one you need.
L-glutamine made by bacterial fermentation of corn, cassava or beet sugar; the source and any vegan statement appear on the supplier's spec.
L-glutamine tested to the USP monograph, used where a compendial grade is required for supplements.
L-glutamine tested to a Food Chemicals Codex or supplier food specification for use in foods and drink mixes.
Finer particle sizes that disperse faster in shakes and drink mixes, sometimes with a lecithin coating.
L-alanyl-L-glutamine and glutamine peptides from wheat protein are sold as separate ingredients that hold up better in liquids.
Compare each result with your own specification when the lot arrives.
Store L-glutamine in tightly closed, lined containers in a cool, dry place away from light and strong odors, and reseal opened packs promptly. Dry crystals are stable, but moisture and heat start conversion to pyroglutamic acid and ammonia, so do not pre-dissolve it for storage. Shelf life or retest date is set by the supplier's specification; assay, loss on drying and micro are the usual retest points for older stock.
Record assay and glutamic or pyroglutamic acid results for each lot, and particle size for micronized grades used in ready-to-mix powders. An ammonia odor on opening is a sign of degradation and a reason to hold the lot.
Facts from regulators and standards bodies, each linked to its source.
21 CFR 172.320 lists L-glutamine among the amino acids that may be safely used as nutrients added to foods, under conditions tied to the protein in the finished food.
Source: ecfr.gov (opens in a new tab)FDA's Substances Added to Food inventory lists L-glutamine with the technical effects flavor enhancer, flavoring agent or adjuvant, and nutrient supplement.
Source: hfpappexternal.fda.gov (opens in a new tab)Health Canada's L-Glutamine natural health product monograph does not permit liquids and solutions, citing lack of stability of the finished product.
Source: webprod.hc-sc.gc.ca (opens in a new tab)This is general information, not regulatory advice. Status differs by country and by how the ingredient is used, so check the rules for your product and market.
Manufacturers and distributors whose own websites say they sell it.
Manufacturer · Raleigh, NC
North American subsidiary of the Ajinomoto Group. It supplies pharmaceutical- and food-grade amino acids made by fermentation, in pack sizes from R&D pails to bulk, plus custom amino acid blends.
Suppliers are in alphabetical order and none pays to appear. Each claim is checked against the supplier’s own website on the date shown. Ask for the specification sheet and a recent COA before you order, and confirm details with the supplier.
Common forms include fermented (plant-sugar) grade, uSP grade, food grade, micronized and peptide-bound forms. Ask each supplier for the specification sheet of the exact grade they quote.
Expect identity, assay, related substances, loss on drying and residue on ignition and heavy metals and microbiology, each with its method, specification and result for that lot.
Store L-glutamine in tightly closed, lined containers in a cool, dry place away from light and strong odors, and reseal opened packs promptly. Dry crystals are stable, but moisture and heat start conversion to pyroglutamic acid and ammonia, so do not pre-dissolve it for storage. Shelf life or retest date is set by the supplier's specification; assay, loss on drying and micro are the usual retest points for older stock.
21 CFR 172.320 lists L-glutamine among the amino acids that may be safely used as nutrients added to foods, under conditions tied to the protein in the finished food. FDA's Substances Added to Food inventory lists L-glutamine with the technical effects flavor enhancer, flavoring agent or adjuvant, and nutrient supplement. Health Canada's L-Glutamine natural health product monograph does not permit liquids and solutions, citing lack of stability of the finished product.
Request a free listing for the ingredients you make or distribute. No paid placement.