Proteolysis and lipolysis of white-brined (Beyaz) cheese during storage: Effect of milk pasteurization temperature

Beyaz cheeses were produced from milk pasteurized at 65 degrees C for 20 min, 75 degrees C for 5 min, or 85 degrees C for 5 min, and investigated at 7, 30, 60, and 90 days of storage. Pasteurization temperature affected significantly the parameters of total solids, fat, titratable acidity, pH, salt, and total free fatty acid of Beyaz cheese. Water-soluble nitrogen fraction (% WSN/TN), caseins (alpha(s1)- and beta-casein), and individual free amino acids were analyzed to evaluate the proteolysis of Beyaz cheese during 90-day storage period. Pasteurization norm did not affect % WSN/TN levels in direct proportion to pasteurization temperature. alpha(s1)-Casein hydrolysis of Beyaz cheeses increased with elevated pasteurization temperature. As the pasteurization temperature increased, beta-casein hydrolysis grade showed a slight decrease. Leucine, lysine, phenylalanine, and valine were found to be dominant in Beyaz cheeses. The total free fatty acid content in cheeses decreased as the pasteurization temperature increased.