Effect of Milk Preacidification on Low Fat Mozzarella Cheese: lII. Post-Melt Chewiness and Whiteness

摘要

The effect of calcium reduction (as a result of milk preacidification) on post-melt chewiness and whiteness of low fat Mozzarella cheese was determined. Four vats (230 kg of milk per vat) of cheese were made in 1 d using no preacidification (control), preacidification pH 6.0 and pH 5.8 with acetic acid, and preacidification to pH 5.8 with citric acid. Cheese manufacture was repeated on four different days using a randomized complete block design. The total calcium content and the water-insoluble calcium content of the cheese were lower in the cheeses made from preacidified milks. The amount of water-soluble and water-insoluble calcium changed during refrigerated storage, as did pH. The post-melt chewiness and whiteness of low fat Mozza- rella cheese were affected by milk preacidification. The largest level of calcium reduction and modification in post-melt chewiness and whiteness occurred in the pH 5.8 citric treatment. Multiple regression analysis of post-melt chewiness and cheese whiteness at 38"C after heating and cooling indicated that both water-insoluble calcium and proteolysis were strongly associated with changes in the post-melt chewiness and whiteness of low fat Mozzarella cheese. High levels of proteolysis and low levels of water-insoluble calcium were associ- ated with decreased post-melt chewiness and whiteness of low fat Mozzarella cheese.