Availability of Calcium (Ca) and Phosphorus (P) from Casein Phosphopeptides (CPP) in Growing Rats

Abstract

Casein phosphopeptides (CPP) enhance the absorption of calcium (Ca) by inhibiting the precipitation of calcium phosphate in vitro, although the effect on in vivo balance is controversial. This study was undertaken to determine the utilization of Ca and phosphorus (P) from CPP itself in growing male and female rats. CPP prepared from a tryptic hydrolysate of whole casein was added to a test diet, 80% of dietary Ca and 100% of dietary P being supplied as CPP. The dietary Ca and P levels were 5g/kg and 4g/kg, respectively. During the 23-day feeding period, a mineral balance study was carried out from days 19 to 22. The apparent Ca, P and magnesium (Mg) absorption rate, and Ca and P retention in the male rats fed the CPP diet were significantly higher than the equivalent values in the male rats fed with control diet (p<0.05). There was no significant difference in apparent Mg retention among the male groups. The apparent P absorption rate, P retention, and Mg absorption rate in the female rats fed the CPP diet w re significantly higher than the equivalent values in the female rats fed the control diet (p<0.05). There was no significant difference in the apparent Ca absorption rate, Ca retention, and Mg retention among the female groups. No significant difference was observed between the CPP diet group and the control diet group with regard to the mineral contents of the serum and kidney. It is suggested that Ca and P from CPP could be well utilized in growing rats.