Use of Protein Fractions Does Not Improve Protein, Mineral Uptake

Use of Protein Fractions Does Not Improve Protein, Mineral Uptake

LAUSANNE, Switzerland--Using modified protein fractions in infant formulas to mimic those of human milk makes no difference on protein uptake or mineral bioavailability, according to an animal study conducted at the Nestle Research Center here; findings were published in the Journal of Nutrition (135:1438-43, 2005). The researchers divided rats into four groups that received diets containing 10-percent protein as casein, beta-casein, a 40-to-60 ratio of casein to whey, or a 40-to-60 ratio of beta-casein to alpha-lactalbumin. Animals on the whey-containing diets showed greater protein utilization and body weight gain compared to those on the casein diets, though there were no differences between the two casein groups or two whey groups. Similarly, the whey diets enhanced absorption of several minerals, including calcium, iron and zinc, compared to the casein diets, but there were no apparent benefits to the use of the casein or whey protein fractions.