Effects of Pasteurization and High-Pressure Processing of Camel and Bovine Cheese Quality, and Proteolysis Contribution to Camel Cheese Softness.

The effects of high-pressure processing (HPP) compared to thermal treatments on the quality of camel vs. bovine cheeses were studied. The study showed that camel milk has a lower microbial load compared to bovine milk, which is maintained during 7 days' storage of the processed milk. The effect of three HPP treatments (350, 450, and 550 MPa for 5 min at 4°C) and two pasteurization treatments (65°C for 30 min and 75°C for 30 s) on the quality of soft unripened camel and bovine milk cheeses were accessed. The cheeses were evaluated for pH, yield, proximate composition, textural and rheological properties, microstructure, and protein profile by SDS-PAGE electrophoresis. The effects of the treatments on cheese's hardness were different between the camel and bovine cheeses; while heat treatment at 65°C for 30 min gave the hardest bovine milk cheese (1,253 ± 20), HPP treatment at 350 MPa for 5 min gave the highest value for camel milk cheese (519 ± 5) (p < 0.05). The hardness of the cheeses was associated with low yield and moisture content. SDS-PAGE electrophoresis revealed that extensive proteolysis might have contributed to the softness of camel cheeses compared to bovine and suggested the involvement of some residual enzyme activities.

Probiotic survival, biological functionality and untargeted metabolomics of the bioaccessible compounds in fermented camel and bovine milk after in vitro digestion.

This study investigated probiotic survival and biological functionality of the bioaccessible fraction of fermented camel milk (FCM) and fermented bovine milk (FBM) after in vitro digestion. Furthermore, untargeted metabolomic analysis was performed to identify the bioaccessible compounds in FCM and FBM, which were produced using starter bacteria (SC), a potential probiotic (Pro) or a combination thereof (SC + Pro), followed by storage (21 d). Survival of Pro and SC + Pro bacteria in FCM was higher than in FBM throughout in vitro digestion. The antioxidant activities of the bioaccessible fractions differed slightly between culture types, whereas the antiproliferative activity of SC was highest, followed by SC + Pro. Antiproliferative activity of the bioaccessible fractions of FCM was greater than for FBM. Untargeted metabolomics of FCM demonstrated discrimination between cultures and from FBM. FCM produced with SC + Pro and Pro had closer clustering than with SC. The bioaccessible fraction of FCM exhibited higher biological functionality compared to FBM.