Fortifying pork liver mixture: Evaluation of protein quality and iron bioavailability – Part 2

Abstract

ABSTRACT Objective To evaluate the protein quality and iron bioavailability of a fortifying mixture based on pork liver. Methods Determinations of protein efficiency ratio, net protein utilization, true digestibility and hemoglobin regeneration efficiency by depletion and repletion were performed. In the depletion phase, the animals (male Wistar rats) received an iron-free AIN–93G diet and in the repletion phase they received the following diets: standard AIN–93G diet, fortifying mixture and standard diet containing heptahydrated ferrous sulfate for comparison. Results For standard AIN–93G diet and fortifying mixture the results were 3.75 and 4.04 for protein efficiency ratio and 3.53 and 3.63 for net protein retention, showing that the presence of pork liver in the diet promoted an increase in protein efficiency ratio and net protein retention (not statistically significant). True digestibility results obtained with the fortifying mixture (97.16%) were higher than those obtained with the standard AIN–93G diet (casein), but without significant difference. The hemoglobin regeneration efficiency values obtained for standard AIN–93G diet, fortifying mixture and standard diet containing heptahydrated ferrous sulfate were 50.69, 31.96 and 29.96%, respectively, showing a statistically significant difference between the control (standard AIN–93G diet) and test (fortifying mixture and standard diet containing heptahydrated ferrous sulfate) samples, but not between the test samples. Conclusion The fortifying mixture showed a high protein efficiency ratio value of 4.04 and a high relative biological value (108%) and it can be added to soups, creams and meats in day-care centers for the prevention of iron-deficiency in children of school age.