Synthesis and Characterization of Canola Oil−Stearic Acid-Based Trans-Free Structured Lipids for Possible Margarine Application

Abstract

Incorporation of stearic acid into canola oil to produce trans-free structured lipid (SL) as a healthy alternative to partially hydrogenated fats for margarine formulation was investigated. Response surface methodology was used to study the effects of lipozyme RM IM from Rhizomucor miehei and Candida rugosa lipase isoform 1 (LIP1) and two acyl donors, stearic acid and ethyl stearate, on the incorporation. Lipozyme RM IM and ethyl stearate gave the best result. Gram quantities of SLs were synthesized using lipozyme RM IM, and the products were compared to SL made by chemical catalysis and fat from commercial margarines. After short-path distillation, the products were characterized by GC and RPHPLC-MS to obtain fatty acid and triacylglycerol profiles, 13C NMR spectrometry for regiospecific analysis, X-ray diffraction for crystal forms, and DSC for melting profile. Stearic acid was incorporated into canola oil, mainly at the sn-1,3 positions, for the lipase reaction, and no new trans fatty acids formed. Most SL products did not have adequate solid fat content or beta' crystal forms for tub margarine, although these may be suitable for light margarine formulation.

Enhancing Plant Seed Oils for Human Nutrition

“…To replace the solid-fat functionality of many hydrogenated oils, the stearate needs to be a major component of the seed oil, approximately 30% of the total fatty acids (Lumor et al, 2007). As one might imagine, living oilseeds do not take too kindly to being stuffed full of margarine, and germination problems are often seen when the stearic acid content of seeds is elevated to these levels (Roberts et al, 2006).…”

Conducting Research at the Interface of Food Science and Nutrition

“…The nutritional properties of lipids strongly depend on their fatty acid and triacylglycerol or glycerophospholipid (TAG or GPL) composition, fatty acid position on the glycerol backbone, and their molecular species (Chapkin, Akoh, & Miller, ; Liang et al., ). Structured lipids (SL) can be designed for nutrition, medical, nutraceutical use (healthful lipids), or for functionality in foods (Akoh, ; Akoh & Kim, ; Kim & Akoh, ; Osborn & Akoh ; Pande & Akoh, ): Physicochemical and functional properties : Lipids with desirable properties such as melting, rheology, plasticity (Seriburi & Akoh, ), oxidative and frying stability, emulsification, trans ‐free alternative (Jennings & Akoh, ; Kadamne, Moore, Akoh, & Martini, ; Kim, Lumor, & Akoh, ; Lumor et al., ; Pande, Akoh, & Shewfelt, ), and edible films are being produced. These include cocoa butter alternatives (Bahari & Akoh, ,b; Jin, Akoh, Jin, & Wang, ; Osborn & Akoh, ), margarines, spreads (Kim, Shewfelt, Lee, & Akoh, ), shortenings, baking fats (Agyare, Addo, Xiong, & Akoh, ; Agyare, Xiong, Addo, & Akoh, ), salad oils (Fomuso, Corredig, & Akoh, ), flavor or terpene esters (Claon & Akoh, ; Wu, Akoh, & Phillips, ), organogels, and edible films (Moore & Akoh, ; Sellappan & Akoh, ) (Figure ). Healthful lipids are being designed for better absorption, reduced calories, disease considerations, immune function modulation, cholesterol reduction, enteral and parenteral nutrition, balanced n‐3/n‐6 ratio (Jennings & Akoh, ), reduction or removal of trans fats, infant growth and development (Zou, Pande, & Akoh, ), and fat substitutes (Akoh, , ).…”

Modifying Vegetable Oils for Food and Non-food Purposes

“…To replace the solid-fat functionality of many hydrogenated oils the stearate needs to be a major component of the seed oil, around 30% of the total fatty acids (Lumor et al 2007) and germination problems are often seen when the stearic acid content of seeds is elevated to these levels (Roberts et al 2006; Clemente unpublished data). However, by combining the silencing of SAD3 with silencing of FAD2 in soybean it has been possible to make viable seeds that have an oleic content in the 50-60% range with stearic around 15-20% (Booth et al 2002).…”