Impact of casein hydrolysates on the ripening parameters and chemical characteristics of Tulum cheese

Abstract This study aimed to investigate the effects of incorporating casein hydrolysed using enzymes from Bacillus licheniformis (endoprotease) or Aspergillus oryzae (endoprotease and exoprotease mixture) on the characteristics of Erzincan Tulum cheese, and to shorten its lengthy and expensive ripening process. Six types of cheese containing different levels of hydrolysed or non-hydrolysed casein were produced and aged for 90 days at 6 ± 1 °C. In experimental cheeses, titratable acidity was found to be 0.73%–1.43%, pH 4.21–4.80, dry matter 47.71%–51.83%, fat 21.71%–25.34%, protein 20.06%–25.77%, water-soluble protein 2.50%–8.25%, ripening index 9.70%–34.88%, total free fatty acids 0.66%–0.99%, lactic acid 1.11%–2.36%, and citric acid 1,168–2,700 ppm. Mesophilic lactic acid bacteria count ranged from 6.28 to 8.69 log CFU/g. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis revealed varying degrees of casein hydrolysis across all trial cheeses during ripening. Overall, the results suggest that using casein hydrolysed with these enzymes could potentially accelerate the ripening process of Tulum cheese.