Properties of Fat

The most difficult property of fat to replace is flavor. Great expenditure of effort has gone into producing a tme butter flavor as flavor boosters in nondairy fat products and in dairy products including milk, cream, butter, and ice cream. Results have led to a successful dupHcation of buttery flavors which closely match the intended target. 

The physical properties of fats and oils have been reviewed (48). 

Sucrose polyesters, which are made by esterilying sucrose with long-chain fatty acids, have the physical properties of fat, but are resistant to digestive enzymes (40). Olestra, a sucrose polyester developed by Procter Gamble, was submitted for regulatory approval in May 1987. In order to faciUtate the approval process, Procter Gamble has since narrowed the scope of its food additive petition to include olestra s use only in savory and extmded snacks. 

Li X et al (2005) Modulation of chondrocytic properties of fat-derived mesenchymal cells in co-cultures with nucleus pulposus. Connect Tissue Res 46(2) 75-82... 

Melting properties, of fats, 10 827 Melting (floating zone) technique, fabrication method for inorganic materials, 7 415t... 

De Man (1983) has reviewed this property of fats. Consistency is defined as (1) an ill-defined and subjectively assessable characteristic of a material that depends on the complex stress-flow relation or as (2) the property by which a material resists change of shape. Spreadabil-ity, a term used in relation to consistency, is the force required to spread the fat with a knife. The definition is similar to that for hardness the resistance of the surface of a body to deformation. The most widely used simple compression test in North America is the cone penetrometer method (AOCS Method Cc 16-60, 1960). More sophisticated rheological procedures are also available. Efforts have been made to calibrate instrumental tests with sensory response. With the cone penetrometer method, penetration depth is used as a measure of firmness. Hayakawa and De Man (1982) studied the hardness of fractions obtained by crystallization of milk fat. Hardness values obtained with a constant speed penetrometer reflected trends in their TG composition and solid fat content. 

Tlie drying property of fats and oils is related to their degree of unsauiraliou, and hence, to iodine values. 

Widak, N. Physical Properties of Fats, Oils, and Emulsifiers, AOCS Press, Oiampaign. IL. 2000. 

Wium, H., Pedersen, P.S., and Qvist, K.B. 2003. Effect of coagulation conditions on the microstructure and the large deformation properties of fat-free Feta cheese made from ultrafiltered milk. Food Hydrocolloids 17, 287-296. 

Kulkarni, S., Rama Murthy, M.K. 1987. Relation between properties of fat and rheological characteristics of butter. Indian. J. Dairy Sci. 40, 232-237. 

Rousseau, D., Marangoni, A.G. 2002. The effects of interesterification on the physical properties of fats. In, Physical Properties of Lipids (A.G. Marangoni, S.S. Narine, eds.), pp. 479-564, Marcel Dekker, New York. 

The American Oil Chemists Society has published Recommended Practice Cj 1-94 for determining the DSC melting properties of fats and oils. The method is limited in terms of accuracy and reproducibility to the determination of onset temperature and completion of melt (Firestone, 1998). 

Birker, P.J.M.W.L., Padley, F.B. 1987. Physical properties of fats and oils. In, Recent Advances in Chemistry and Technology of Fats and Oils (R.J. Hamilton, A. Bhati, eds.), pp. 1-12, Elsevier Applied Science, London. 

Blaurock, A.E. 2000. Fundamental understanding of the crystallization of oils and fats. In Physical Properties of Fats, Oils and Emulsifiers (N. Widlak, ed.), AOCS Press, Champaign. 

Sato, K., Ueno, S., Yano, J. 1999. Molecular interactions and kinetic properties of fats. Prog. Lipid Res. 38, 91-116. 

Q Explain how unsaturations affect the properties of fats and oils. Compare the properties of saturated fats with those of polyunsaturated oils and partially hydrogenated vegetable oils. 

Melting properties of fats in the mouth are important. Generally, consumers can detect a greasy characteristic if more than 3 percent solids remain in spreads at mouth temperatures, or if more than 5-6 percent fat solids remain in baked, fried and snack foods. Thus, doughnuts and bakery products are best eaten... 

Source From G. Ohloff, Fats as Precursors, in Functional Properties of Fats in Foods, J. Solms, ed., 1973, Forster Publishing. 

Fats provide fundamental structural and textural attributes to a wide range of consumer products, including lipstick, chocolate, and everyday products such as butter and margarine (1, 2). Within these fat-based products, certain textural properties are required to meet desirable sensory attributes to gain consumer acceptance (3). This has led to an increase in research efforts on the physical properties of fats, particularly their rheology. 

These various examples depict the effects of processing conditions on the physical properties of fats and demonstrate that external crystallization conditions, such as cooling rate and storage temperature, can have dramatic effects on the final measurable properties of a fat. 

Solid Fat Content and the Fat Crystal Network The solids content of a fat crystal network is of critical importance to the final physical properties of the system. Generally, an increase in SFC leads to an increase in fat firmness. The SFC measurement has been widely used as a determinant quantity for the structural properties of fat systems. Estimations for commercial plastic fats, including butter, predict firmness increases of 10% for every percent increase in SFC (45). As a result, models used to describe the rheological properties of fats incorporate references to SFC values. 

---