Physicochemical Properties of Conjugated Linoleic Acid‐Rich Soy Oil

Abstract

CLA-rich soy oil (CLARSO) has been produced by linoleic acid isomerization in soy oil TAG. The objective was to determine the physicochemical properties of the novel CLARSO relative to conventional refined bleached deodorized soy oil (RBDSO). Iodine value decreased in CLARSO samples despite unsaturation being unchanged, probably because conjugated double bonds in triacylglycerol (TAG) of CLARSO impede the complete addition of iodine. Thermal analysis by differential scanning calorimetry showed the melting point temperature increased with the increase in the CLARSO CLA concentration, and melting point broadening occurred in CLA contained samples. Dynamic viscosity of CLARSO conducted from 4 to 44°C increased with the increase in CLA concentration, relative to RBDSO. Greatest viscosity differences occurred at the lower temperatures. Refractive indices and density were not greatly affected. The change in physical properties was attributed to the increased intermolecular hydrophobic interaction force due to conjugated double bonds and trans,trans isomers, relative to RBDSO.

CLA‐Rich Soy Oil Shortening Production and Characterization

“…In addition, the CLA-rich shortenings also have a higher SFC (% SFC) as well as higher latent heat of crystallization and melting than the soy oil controls indicating a comparatively higher crystalline fraction. Thus, CLARSO produced firmer shortenings than did Ruan and Proctor [13] found that CLARSO had a higher melting temperature and viscosity than refined, bleached, deodorized (RBD) soy oil. These differences were attributed to greater intermolecular hydrophobic interaction forces of the CLA conjugated double bonds in the transtrans fatty acids of CLARSO.…”

Effect of trans, trans CLA Egg Enrichment from CLA-Rich Soy Oil on Yolk Fatty Acid Composition, Viscosity and Physical Properties

“…In addition, triplicate control, soy control, and CLA-rich eggs containing the highest dietary CLA concentration were analyzed in duplicate after 5 and 10 days of refrigerated storage [ N = 18]. An AR-2000 Rheometer was used for viscosity analysis . Each yolk sample was vortexed for 20 s and 2 aliquots of yolk were dispensed from a 1 mL auto pipet on the lower rheometer plate.…”

“…An AR-2000 Rheometer was used for viscosity analysis. 19 Each yolk sample was vortexed for 20 s and 2 aliquots of yolk were dispensed from a 1 mL auto pipet on the lower rheometer plate. A 40 mm diameter sand-blasted geometry was applied to the sample surface at a constant shear rate of 100 s −1 .…”

Strategies for Producing and Incorporating Conjugated Linoleic Acid–Rich Oils in Foods

“…There is no research available on CLA-rich oil use in salad dressing preparation. However, the greater viscosity that CLA-rich oil experiences at refrigerator temperatures, relative to conventional soybean oil (Ruan & Proctor 2014), may be useful in salad oil and refrigerated sauces to enable suspension of particles and maintain a richer, thicker texture.…”