Polymorphic behavior of high stearic high oleic sunflower oil stearins

JAIME A RINCON CARDONA; ROBERTO J CANDAL; MARIA L HERRERA

Campinas

Otro; Activity Report 2012 Brasilian Sincrotron Light Laboratory; 2011

CNPEM/LNLS

Polymorphism- the existence of two or more distinct crys-talline forms with different types of crystal packing and ther-modynamic stabilities of the same substance- is a function of processing conditions, time and temperature of storage [1]. Polymorphism results from the different possibilities of lat-eral packing of the fatty acid chains and of the longitudinal stacking of molecules in lamellae. These two levels of or-ganization 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 man-ufacturers to eliminate or reduce the trans fat from their prod-ucts. In some applications like baked goods and confectionery a certain amount of solids is crucial to obtain the desired prod-uct 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 devel-oped recently and will be commercialized soon. Although polymorphism is very relevant regarding industrial applica-tions, the polymorphic behavior of these systems has not been described yet. 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.