Utilization of calcium in breads highly fortified with calcium as calcium carbonate or as dairy calcium

White pan breads were prepared with flour highly fortified with calcium (Ca ), using Ca carbonate (Ca, 38.8%) or a high Ca whey powder (Ca, 5.6%) as th e Ca source; bread was also prepared using Ca carbonate plus lactose. Ca wa s added to flour at 924 mg/100 g of flour, a level 4.4 times higher than sp ecified under the U.S. enrichment standards. Breads were dried and finely g round to prepare test diets (Ca, 0.5%) which were then fed to growing rats for four weeks (growth phase) or eight weeks (approaching maturity). At eit her interval, femur ash content, femur Ca content, femur strength, or Ca ab sorption values did not differ significantly among groups fed breads fortif ied either with Ca carbonate, Ca carbonate + lactose, or whey. Thus, breads can be highly fortified with Ca carbonate to be labeled as "high" in Ca, a nd this Ca may be as well absorbed and utilized as dairy Ca.