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Abstract During the last decade, feeding on low-fat and non-fat soft cheese products has become more important for human health and trend. Low-fat cheese is restricted to fat content equal or less than 3 g per 100-g serving,. In general, full-fat soft cheese contains about 40- 45% fat in dry matter but not more than 60%. Traditional soft cheese were manufactured using standardized buffalo’s milk contained 4.2%, 2.0%, 1.0% and 0.05% fat for control full fat, half-fat, low-fat and free-fat soft cheese, respectively. In addition, ultrafiltrated soft cheese were manufactured using standardized buffalo’s milk retentate. Standardized full fat, half-fat, low and free-fat milk were divided into 8 portions. The first and second portions were used as control without starter culture, the third to the eights portions were manufactured using different starter cultures as follows: A1= Lactoccoccus lactis subsp. creamoris, lactoccoccus lactis subsp.lactis, streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus and lactobacillus helveticus (White Daily 82). A2= Lactoccoccus lactis subsp. creamoris, lactoccoccus lactis subsp. lactis, streptococcus thermophiles and lactobacillus delbrueckii subsp. bulgaricus (White Daily 42). V1= Lactoccoccus lactis subsp. creamoris, lactoccoccus lactis subsp. lactis, streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus and lactobacillus helveticus (White Daily 82) and streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus (YF-L811). V2= Lactoccoccus lactis subsp. creamoris, lactoccoccus lactis subsp. lactis, streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus and lactobacillus helveticus (White Daily 82) and streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus (YC-X11). V3= Lactoccoccus lactis subsp. creamoris, lactoccoccus lactis subsp. lactis, streptococcus thermophiles and lactobacillus delbrueckii subsp. bulgaricus (White Daily 42) and (streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus (YF-L811). V4= Lactoccoccus lactis subsp. creamoris, lactoccoccus lactis subsp. lactis, streptococcus thermophiles and lactobacillus delbrueckii subsp. bulgaricus (White Daily 42) and (streptococcus thermophiles, lactobacillus delbrueckii subsp. bulgaricus (YC-X11). Three replicates were traditionally manufactured and stored at 5± 1°C. Ultrafiltration was carried out using standardized buffalo’s milk retentate concentration factor of ˷ 3.5 and the average composition of the used retentate was: 38.23 % total solids, 15.44 total protein, 16.1% fat, 4.3%lactose and 2.4 ash for composition of full fat retentate. While, the average composition of low fat retentate 27.55 % total solids, 16.81 total protein, 3.5% fat, 4.76%lactose and 2.5 ash. The starter culture used was V1 (White Daily 82 and YF-L811) which gave the most acceptable traditional soft cheese properties. Three replicates of full, half, low and free fat soft cheese were manufactured using UF technique and the resultant soft cheese were stored at 22 and 5± 1°C. Samples were analyzed within 0, 15, 30, 45, 60, 75, 90, 105, 120, 150, and 180 days of storage and examined for chemical, microbiological, rheological and organoleptic characteristics. Results designated that, the use of exopolysaccharide producing strains in V1 mixture gave the highest soluble nitrogen / total nitrogen, soluble tyrosine and soluble tryptophan contents and the rate of accumulation of total volatile fatty acids than all other cheese treatments. In addition, the highest lactic acid bacterial counts were found in fresh V1 free fat soft cheese and V2. Lactic acid bacterial count gradually decreased within 120 days of storage. Yeast and mould counts were less than the standards within first 60 days of the storage period. Total viable bacterial counts slightly increased in all cheese samples as the storage period progressed. Hardness, cohesiveness, chewiness and adhesiveness properties were high in control full-fat as compared with all other free fat cheese. Generally, production of free fat soft cheeses using acid producing and exopolysaccharide producing lactic acid bacteria as starter culture could be recommended to produce healthy and acceptable cheese. Key words: Full fat, Low-fat, Free fat soft cheese; Exopolysaccharide producing lactic acid bacteria; Rheological properties and storage period. |