Effect Of Using Whey Protein Concentrates on Physicochemical, Rheological and Sensory Properties of low-fatIraqiSoft Cheese

Abstract

Considering to the urgent need to manufacture low-fat low calorieIraqi soft cheese with a highly rheological and sensory properties similarto soft cheese made from full fat . This study was conducted and aimed to use whey protein concentrates (WPC) as a fat replacer and to study its role in improving physicochemical, rheological and sensory properties of the manufactured cheese. WPC was added to skimmed milk in different ratios 0.5, 1.0, 1.5, 2.0 % which reveled to treatments B1, B2, B3, B4 respectively, In addition to positive control treatment C+ which made from whole milk and negative control treatment Cـــwhich made from skimmed milk without WPC .The chemical tests that involved the % of moisture, protein, fat, lactose, ash, soluble nitrogen and non-protein nitrogen and the physical tests involved the total acidity, pH, compression and elasticity were made beside the sensory evaluation were conducted after processing directly and during storageat (5 ± 1) º C for 14 days The results indicated that the WPC treatments had a high moisture content than C+ and Cـــwhich it was 59.00 and 63.74 % for C+ and Cـــrespectively while it ranged from 64.87 to 66.50 % for WPC treatments, when moisture contents was follow up during storage at ( 5±1) C for 14 days the results indicated a significant reduction for all the treatments values. WPC treatments had a higher protein percentage than the Cـــ treatment. Fat content was decreasedsignificantly in all skimmed milk WPC treatments but the lactose percentage was converged in all treatments. Total acidity percentageis the highest in WPC treatments compared with C+ and Cـــ treatments. WPC addition improved the rheological tests results (compression and elasticity) of produced cheese compared with Cـــ treatment, also the WPC addition increased cheese yeild and improved the sensory properties of low-fat soft cheese the decreased the energy value as well.