This work reports the effects of diets with ripening cheese Jeziorański or Tilsit- type on the weight of particular body organs, values of haematological indices and the content of some minerals in the liver and blood plasma in growing Wistar rats. The cheeses were salted in 20% solution of sodium chloride and sodium chloride/potassium chloride mixture (1:1 w/w) for 25, 50, 75 and 100% of the standard salting time. The correlation was found between the diet and weights of liver and kidneys but not between the diet and the weights of heart and spleen. The haematopoietic system of rats was not found to be influenced by cheese diets. The haematological indices were within the physiological norms. The concentrations of sodium and potassium in the liver of rats were significantly (P=0.05) dependent on the diet. The concentrations of sodium and calcium in the blood plasma of rats fed cheese diets were within the range of values assumed regular. The diets with the cheeses being salted in the sodium chloride/potassium chloride mixture increased significantly the concentration of potassium in the blood plasma of rats.
The calcium bioavailability from unripening cheeses produced by high heat-acid coagulation of milk was the major purpose of this work. The cheeses may supply a significant portion of the calcium needs for humans because of their total calcium content (from 747 to 605.6 mg/100 g cheese) and satisfactory Ca/P ratio (from 1.55 to 1.85). High bioavailability of calcium from the cheeses, expressed as the apparent absorption (from 57.4 ±0.6 to 60.5 ±1.1%) and retention (from 52.0±1.1 to 52.2±0.6%) make these dairy products to be an important source of available calcium in the human diet.
Semi-hard and hard ripening cheeses were examined after being salted in a 20% solution of sodium chloride or sodium chloride and potassium chloride mixture (1:1 w/w) for 25 and 100% standard salting time. Bioavailability of magnesium from the cheese diets, as expressed in the terms of apparent absorption and retention, and liver and biood levels of magnesium, was determined in growing Wistar rats during a 6-week experiment. The addition of potassium chloride to brine was found to decrease significantly the intake of magnesium for rats fed diets with examined cheeses. The type of cheese, composition of brine, salting time and interactions of these factors significantly influenced the values of apparent absorption and retention of magnesium. The content of magnesium in the liver of rats was dependent on the type of cheese and that in the blood plasma was dependent on the composition of brine used for cheese salting. Feeding rats diets with the cheeses being salted in the mixture of the chlorides did not cause more serious disturbances in absorption and metabolism of magnesium in rats.