Protein digestibility, available lysine and amino acid profiles in commercial milk-based infant formula of China.

摘要

Protein content and quality, e.g. available lysine, in vitro protein digestibility and amino acid profiles of 14 commercial milk infant formulas available in China were determined. All of the formulas studied were based on milk enriched with whey. The average protein content of the 8 domestic infant formulas (13.58 +or- 0.93%) was significantly higher than that of the 6 imported infant formulas (11.63 +or- 1.16%). The mean available lysine content of the imported milk infant formulas was 68.33 +or- 10.09 mg/g protein, while that of the domestic formulas was 65.35 +or- 6.49 mg/g, both values are similar to that of human milk. In vitro protein digestibility values were in the ranges 89.71-93.70% for the imported formulas and 88.19-93.82% for the domestic formulas. Amino acid profiles of the imported and domestic formulas were similar; contents of all amino acids, except tryptophan, in the 14 milk infant formulas were higher than those established by law. No statistically significant differences in protein quality and amino acid profiles between the domestic and imported milk infant formulas examined were found.