الفهرس 
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Abstract
This study was carried out to evaluate the effect of the partial substitution of NaCl with different levels of KCl and MgCl2 on the manufacture and characteristics of Kareish and Domiatti cheese. Also, the effect of addition modified starch as fat replacers with partial substitution of NaCl with KCl on imitation Domiatti cheese characteristics were studied. Kariesh and Domiatti cheese was made by using different concentrations of salts namely NaCl with KCl or MgCl2 (1:1, 2:1 and 1:2 %). Kariesh and Domiatti cheese being made with only 3 and 8%, respectively NaCl as control. Imitation Domiatti cheese manufactured with the same steps of Domiatti cheese using skimmed milk with mixture of each of sodium and potassium chloride with ratio (1:1) and different levels of starch (0.5, 1 and 2%). All treatments analyzed at (fresh, 7 and 15 days) for Kariesh cheese and (fresh, 7, 15, 30 and 60 days) for Domiatti and imitation Domiatti cheese. Chemical analysis were (Total protein (TP), non-protein nitrogen (NPN),water soluble nitrogen (WSN), total solid (TS), pH values and minerals of (Na, K and Mg)), as well as microbial analysis, organoleptic indices (flavour, body & texture and appearance & color) and rheological properties (hardness, cohesiveness, springiness, adhesiveness, gumminess and chewiness) were studied. The main results can be summarized as follows: Kariesh cheese: It could be notice that the total solid is inversely proportional to substitution percentage of NaCl with KCl or MgCl2. On the other hand, cheese yield is directly proportional to substitution percentage of NaCl with KCl or MgCl2. The replacement of NaCl with MgCl2 by the ratio (1: 2) enhanced the organoleptic and texture properties of the cheese comparing with the control. NaCl retention percentage in Kareish cheese curd was the highest, compared with other salts, followed by KCl and then MgCl2. Hardness, gumminess and chewiness were significantly lower (P> 0.05) in Karish cheese made with the partial substitution of sodium chloride (KCl or MgCl2) than cheese salted with sodium chloride alone (control). Cohesiveness, adhesiveness and springiness were significantly higher in cheese salted with NaCl/ KCl or NaCl/MgCl2 mixtures. Domiatti cheese: The results were indicated that cheese yield is inversely proportional to substitution percentage of NaCl with MgCl2. Generally, a significant decrease in total solid was recorded in all treatments compared to the control. The replacement of NaCl with KCl by the ratio (1NaCl: 1KCl) enhanced the organoleptic and texture properties of the cheese comparing with the control. The salt retention in Domiatti cheese curd is inversely proportional to substitution percentage of NaCl with KCl or MgCl2. The maximum decreasing of salt retention had recorded by the added of NaCl: MgCl2 (1:2). On the other hand the ability of water binding of Domiatti cheese curd is directly proportional to substitution percentage of NaCl with KCl or MgCl2. Values of hardness, gumminess and chewiness were significantly lower (P> 0.05) in Domiatti cheese made with the partial substitution of sodium chloride (KCl or MgCl2) than control. The value of cohesiveness, adhesivenss and springiness were significantly higher in cheese salted with NaCl/ KCl or NaCl/MgCl2 mixtures than control. Imitation Domiatti cheese: Cheese yield is directly proportional to increase concentration of modified starch and all the three treatments are higher than negative control and increase closely to positive control. Total solid content increase during storage period. NPN, WSN, TP ratios and pH value were significantly higher in control compared with the different levels of addition and negative control. The addition of modified starch with concentrations of (1 and 2%) enhanced the organoleptic and texture properties of the cheese comparing with the negative control and it near by the positive control in its sensory properties. Values of hardness increased with the decrease of fat percent. On the other hand, the adhesivenss decreased with the decrease of fat percent. The results of scanning electron microscope indicated that the presence of fat in positive control make a positive effect on solubility of addition salts. On the other hand scanning show big sharp crystals of salts in negative control. Increasing additions of starch enhanced the solubility of salts in cheese like positive control compared with negative one. In conclusion, evaluate the vital role and sensory properties revealed that Kariesh and Domiatti cheese manufactured with partial substitution of NaCl with KCl or MgCl2, it was so smooth compared to control and have better yield than control. Addition of starch with 1 or 2% enhanced sensory properties compared with negative control and it raise in its properties closely to positive control. Also, the yield increase gradually by raising concentrations of starch.