الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The aim of the study is to take advantage of the functional properties of goats’ and camels’ milk fat through fractionation using dry crystallizations into different fractions in melting point, chain length, degree of saturation and unsaturation, and the fatty acids it contains.
Camels’ and goats’ milk fat were separated into liquid (L) and solid (S) fractions whose chemical and physical properties were studied. Results indicated that, the camels’ and goats’ milk fat were fractionated into liquid and solid fractions at (20°C) for goats’ and (30°C) for camels’ milk fat. Liquid fractions were rich in short chain fatty acids and unsaturated fatty acids, while long chain saturated fatty acids dominated the composition of solid fractions. Fatty acid profile of camels’ milk fat indicated lower values of total short chain and higher values of total long chain and compared to goat milk fat. Cholesterol content, free fatty acids and iodine value were higher in the liquid fractions than solid fractions. Goats’ milk fat fractions showed lower cholesterol content and iodine values as compared with camels’ milk fat, the being lowest in solid fractions. Goats’ and camels’ milk fat fractions were used to prepare functional ice cream and processed cheese spreads.
Functional ice cream (8%fat) was prepared by substitution milk fat with (liquid melting fraction (LMF) solid melting fraction (SMF) fractionated at 20 and 30⁰C and LMF: SMF (2:1 v/v) of goats’ milk fat as camels’ milk fat, respectively. With increasing the melting point of the fraction used, viscosity of ice cream mixes and melting resistance of ice cream were gradually increased with a corresponding decrease in the amount of adsorbed protein on the surface of fat globules. Overrun and fat destabilization were affected adversely by the increase in the melting point of the fraction used.
Functional processed cheese spreads (PCSs) were made with the liquid fractions affect textural profile with the increasing hardness by increased melting point. Meltability and oil separation index of PCSs were affected by the substitution of butter with liquid fractions. Meltability and oil separation index decreased with the increasing melting point of the liquid fraction. Storage at 5±2 ̊C for 3 months of PCSs sample were decreased pH, while soluble nitrogen, meltability value, total volatile fatty acids and oil separation increased.
The organoleptic properties of both functional ice cream and PCSs were made from liquid fractions of goats’ and camels’ milk fat in all treatments were acceptable with some differences between them based on the chemical and physical properties of the fractions of fat used.
Concluded high-performance functional ice cream (8% fat) can be produced using goats’ and camels’ milk fat fractions S20 and L30, respectively which results in the best ice cream quality characteristics. Possibility to improve the nutritional and technological functional PCSs technology using liquid goats’ and camels’ milk fat fraction level 50%