Proximate Composition, In Vitro Protein Digestibility, and Micronutrient Density of Commercial Pea, Faba Bean, and Lentil Protein Isolates and Concentrates

ABSTRACT The nutrient composition and in vitro digestibility of twenty‐seven commercial pulse protein isolates (PI) and protein concentrates (PC) derived from pea, faba, and lentil, and two soy protein isolate controls were tested using consistent analytical methods to understand compositional variability amongst products manufactured by different suppliers. Principal component analysis (PCA) and maximum likelihood factor analysis (MLFA) were applied to model the compositional and amino acid data to determine where the variability between protein products lay. MLFA delineated between isolates and concentrates based upon protein and total dietary fibre content, while moisture and fat variability could be used to differentiate samples within the PI or PC groupings. PCA score charts distinguished between isolates and concentrates due to higher relative concentrations of amino acids in the isolates, with glutamine/glutamic acid contributing to this distinction. Separation according to crop type within PI and PC groupings based upon the arginine and phenylalanine content was also evident. Sodium, potassium, magnesium, and iron micronutrients also contributed to the variability between PI and PC samples. Calculated amino acid scores showed all samples contained sufficient concentrations of essential amino acids to meet FAO requirements established for preschool‐aged children. PI samples had higher in vitro digestibility than PC samples with minimal variability within the groupings.