Determination of free and/or total proteinogenic L-α-amino acids and taurine in all forms of infant, adult, and/or pediatric formulas was reported. Structures to be excluded include, but are not necessarily limited to, methionine sulfone, methionine sulfoxide, cysteic acid, and lysine derived Maillard products. Any analytical technique that meets the method performance requirements is acceptable. It is expected that multiple methods will be required to completely fulfill the requirements. Suitable methods will include blank check samples, and check standards at the lowest point and midrange point of the analytical range.