Effect of acidification temperature and acid on the yield and quality of cheese produced from UF-concentrated whey

Unconcentrated and ultrafiltration (UF)-concentrated whey were used for che ese manufacture with lactic, citric or hydrochloric acid as acidification m edia. The effect of the acidification temperature combined with the concent ration level and the type of acid on the process yield, the protein and sol ids retention as well as on the quality characteristics of the product was examined. Unconcentrated whey resulted in 3.8% cheese yield, 20.0% whey sol ids retention and 79.3% protein retention in the cheese. Whey concentrated to 5:1 and 20:1 resulted in 2.3% and 1.7% cheese yield, 12.2% and 8.2% soli ds retention and 57.0% and 37.7% protein retention, respectively. Both, the texture and the flavor of the products were negatively affected by the inc rease of the concentration level of the whey. Cheese produced from UF-conce ntrated whey had poor sensory characteristics not affected significantly by the type of acid. The acidification of the whey at the final stage of heat ing resulted in products with the most acceptable flavor. Lactic acid addit ion to unconcentrated whey resulted in lower product yield (2.8%) compared to citric and hydrochloric acid (4.8% and 3.8%, respectively), attributed t o lower solids retention. However, UF-concentrated whey presented similar y ields not depending on the acidification medium.