To determine the potential bioavailability of macroelements (Ca, Mg, P, K), probiotic ice cream samples (Lactaseibacillus paracasei L-26, Lactobacillus casei 431, Lactobacillus acidophilus LA-5, Lactaseibacillus rhamnosus and Bifidobacterium animalis ssp. lactis BB-12) from sheep's milk with inulin, apple fiber and inulin, or apple fiber and control samples were submitted to in vitro digestion in the mouth, stomach and small intestine. The bioavailability of calcium in the ice cream samples ranged from 40.63% to 54.40%, whereas that of magnesium was 55.64% to 44.42%. The highest bioavailability of calcium and magnesium was shown for the control samples. However, adding 4% inulin reduced the bioavailability of calcium by about 3-5% and magnesium only by about 5-6%. Adding 4% apple fiber reduced the bioavailability of calcium by as much as 6-12% and magnesium by 7-8%. The highest bioavailability of calcium was determined in ice cream with L. paracasei, and the highest bioavailability of magnesium was determined in ice cream with L. casei. The bioavailability of phosphorus in ice cream ranged from 47.82% to 50.94%. The highest bioavailability of phosphorus (>50%) was in sheep ice cream fermented by B. animalis. In the control ice cream, the bioavailability of potassium was about 60%. In ice cream with inulin, the bioavailability of potassium was lower by 3-4%, and in ice cream with apple fiber, the bioavailability of potassium was lower by up to 6-9%. The bioavailability of potassium was significantly influenced only by the addition of dietary fiber. The results of the study confirmed the beneficial effect of bacteria on the bioavailability of Ca, Mg and P.
Keywords: bioavailability; ice cream; in vitro; macroelements; prebiotic; probiotic; sheep milk.