Effect of milk preacidification on low fat Mozzarella cheese: III. Post-melt chewiness and whiteness

The effect of calcium reduction las a result of milk preacidification) on p ost-melt chewiness and whiteness of low fat Mozzarella cheese was determine d. Four vats (230 kg of milk per vat) of cheese were made in 1 d using no p reacidification (control), preacidification pH 6.0 and pH 5.8 with acetic a cid, and preacidification to pH 5.8 with citric acid. Cheese manufacture wa s repeated on four different days using a randomized complete block design. The total calcium content and the water-insoluble calcium content of the c heese were lower in the cheeses made from preacidified milks. The amount of water-soluble and water-insoluble calcium changed during refrigerated stor age, as did pH. The post-melt chewiness and whiteness of low fat Mozzarella cheese were affected by milk preacidification. The largest level of calciu m reduction and modification in post-melt chewiness and whiteness occurred in the pH 5.8 citric treatment. Multiple regression analysis of post-melt c hewiness and cheese whiteness at 38 degreesC after heating and cooling indi cated that both water-insoluble calcium and proteolysis were strongly assoc iated with changes in the post-melt chewiness and whiteness of low fat Mozz arella cheese. High levels of proteolysis and low levels of water-insoluble calcium were associated with decreased post-melt chewiness and whiteness o f low fat Mozzarella cheese.