CHEMICAL, TECHNOLOGICAL, RHEOLOGICAL AND ORGANOLEPTIC PROPERTIES Of SPREAD PROCESSED CHEESE.

Abstract

This study was carried out to study the possibility of using some dairy products such as (Labenah, Feta cheese made by U.F. and Ricotta cheese made from Mozzarella cheese whey, which are available in many dairy factories as substitute for Ras cheese (ripened or semi-ripened) at ratio 50% or 100% in the manufacture of spread processed cheese. The effect of substituting these products on physicochemical, rheological and organoleptic properties of spread processed cheese was also studed during storage period up to 3 months at 5 • c. The obtained results could be summarized as follows: Spreads processed cheese (PCSs) made by substituting semi-ripened or ripened Ras cheese for all treatments were significantly lower in dry matter (DM) values, Total protein/ dry matter(TP/DM), and higher significantly in fat/dry matter (F/DM) as compared with control. This was more pronounced when substituting semiripened Ras cheese more than the ripened cheese. In all treatments, significantly lower pH values ,soluble nitrogen (SN) and total protein (TP) were observed , and significantly higher in titratable acidity % ,fat/ total nitrogen (F/ TN) and also higher significant in casein / total N nitrogen than the control. Substituting of Ras cheese in all treatments led to highly significant in meltability values in ripened Ras cheese more than semi-ripened as compared with control at ratio 50%. Substituting of semi-ripened Ras cheese by 50% from Labenah or Ricotta cheese resulted in an increase in the oil separation , while using Feta cheese at the same ratio resulted in lower oil separation. No oil separation occurred when substituting 100% semi-ripened Ras cheese with any substitutes.In all treatments, the hardness of cheeses was highly significant, while it was lower during the storage period than control, and it was less in semi-ripened case than the ripened Ras cheese. Significantly higher values of chewiness, adhesiveness and gumminess than the control, and lower in cohesiveness values. PCSs made by replacing Ras cheese for all treatments were highly significant in elasticity values as compared with control. On the other hand, when substituting 50% semi ripened Ras cheese with Labenah resulted in similar elasticity in case of replacing ripened Ras cheese by Feta cheese or Ricotta cheese at ratio 50% and 50%, 100% respectively. They were significantly different in organoleptic properties of PCSs for all treatments. Substituting of Ras cheese resulted hn significant decrease in flavour values, but it was the best when using semi-ripened, while the texture was similar or better than the control, when substituting the semi-ripened Ras cheese at ratio 50%. Substituting ripened Ras cheese with Feta cheese or Ricotta cheese at ratio 50% resulted to the best texture than control.