Polymorphic behavior during isothermal crystallization of hard stearin high oleic sunflower oil

JAIME A RINCON CARDONA; ROBERTO J CANDAL; MARÍA LIDIA HERRERA

Honolulu, Hawaii

Congreso; Annual Meeting of The American Crystallographic Association; 2013

American Crystallographic Association

Polymorphism- the existence of two or more distinct crystalline forms with different types of crystal packing and thermodynamic stabilities of the same substance- is a function of processing conditions, time and temperature of storage [1]. Polymorphism results from the different possibilities of lateral packing of the fatty acid chains and of the longitudinal stacking of molecules in lamellae. These two levels of organization are easily identifiable from the short- and long spacings observed by X-ray scattering at wide (WAXS) and small (SAXS) angles, respectively [2]. FDA rule about trans fat that was effective from January 1st 2006 and trans fat rules issued in many other countries encouraged food product manufacturers to eliminate or reduce the trans fat from their products. In some applications like baked goods and confectionery a certain amount of solids is crucial to obtain the desired product texture or appearance. One of the strategies developed to replace trans fat content in foods is the modification of fatty acid (FA) composition through plant breeding [3]. A new high stearic high oleic (HSHO) sunflower oil variety was developed recently and will be commercialized soon. As polymorphism is very relevant regarding industrial applications, the aim of the present work is to describe the polymorphic behavior during isothermal crystallization of two sunflower oil stearins developed as trans fat replacers.