Chemical and enzymatic interesterification of tristearin/triolein‐rich blends: Microstructure and polymorphism (original) (raw)
Related papers
European Journal of Lipid Science and Technology, 2008
Blends of high-oleic sunflower oil and fully hydrogenated canola oil were subjected to enzymatic and chemical interesterification using Candida antarctica lipase (5%) and sodium methoxide (0.3%), respectively. The effect of each interesterification process was determined by comparing the triacylglycerol (TAG) composition, solid fat content (SFC) profiles and thermal properties of the blends before and after interesterification. Interesterification resulted in a decrease in the concentration of triunsaturated and trisaturated TAG and an increase in the proportion of mono-and disaturated TAG. These alterations in TAG composition and the presence of a greater variety of TAG species upon interesterification was correlated with a broader melting transition by differential scanning calorimetry and, ultimately, a lower melting point for the interesterified blends. Much broader ranges in plasticity were observed for the interesterified blends (chemically and enzymatically) compared to the physical blends. Even though ideal solubility of stearin in oil was observed, the value predicted by the Hildebrand model was higher than the actual amount. Crystallization kinetic parameters (Avrami index and rate constant) were similar for the non-interesterified, enzymatically interesterified and chemically interesterified blends when compared as a function of SFC. Results from this work will aid in the formulation of more healthy fat and oil products and address a critical industrial demand in terms of formulation options for spreads, margarines and shortenings.
Food Chemistry, 2013
Palm stearin (PS), palm kernel oil (PKO) and soybean oil (SBO) blends were formulated according to Design Expert 8.0.4 (2010). All the sixteen oil blends were subjected to chemical interesterification (CIE) using sodium methoxide as the catalyst. The effects of chemical interesterification on the slip melting point (SMP), solid fat content (SFC), triacylglycerol (TAG) composition and polymorphism were investigated. Palm based trans-free table margarine containing PS/PKO/SBO [49/20/31, (w/w)], was optimally formulated through analysis of multiple ternary phase diagrams and was found to have quite similar SMP and SFC profiles as compared with commercial table margarine. This study has shown that blending and chemical interesterification are effective in modifying the physicochemical properties of palm stearin, palm kernel oil, soybean oil and their blends.
Journal of the American Oil Chemists' Society, 1998
Fat blends, formulated by mixing a highly saturated fat (palm stearin or fully hydrogenated soybean oil) with a native vegetable oil (soybean oil) in different ratios from 10:90 to 75:25 (wt%), were subjected to chemical interesterification reactions on laboratory scale (0.2% sodium methoxide catalyst, time = 90 min, temperature = 90°C). Starting and interesterified blends were investigated for triglyceride composition, solid fat content, free fatty acid content, and trans fatty acid (TFA) levels. Obtained values were compared to those of low-and high-trans commercial food fats. The interesterified blends with 30-50% of hard stock had plasticity curves in the range of commercial shortenings and stick-type margarines, while interesterified blends with 20% hard stock were suitable for use in soft tubtype margarines. Confectionery fat basestocks could be prepared from interesterified fat blends with 40% palm stearin or 25% fully hydrogenated soybean oil. TFA levels of interesterified blends were low (0.1%) compared to 1.3-12.1% in commercial food fats. JAOCS 75, 489-493 (1998).
Journal of Food Lipids, 2009
Blends of canola oil (CO) and fully hydrogenated cottonseed oil (FHCSO), with 20, 25, 30, 35 and 40% FHCSO (w/w) were interesterified under the following conditions: 0.4% sodium methoxide, 500 rpm stirring, 100C, 20 min. The original and interesterified blends were examined for triacylglycerol composition, melting point, solid fat content (SFC) and consistency. Interesterification caused considerable rearrangement of triacylglycerol species, reduction of trisaturated triacylglycerol content and increase in disaturated-monounsaturated and monosaturated-diunsaturated triacylglycerols in all blends, resulting in lowering of respective melting points. The interesterified blends showed reduced SFC at all temperatures and more linear melting profiles if compared with the original blends. Consistency, expressed as yield value, significantly decreased after the reaction. Iso-solid curves indicated eutectic interactions for the original blends, which were eliminated after randomization. The 80:20, 75:25, 70:30 and 65:35 (w/w) CO: FHCSO interesterified blends showed characteristics which are appropriate for their 3 Corresponding Journal of Food Lipids 16 (2009) 362-381. All Rights Reserved. © 2009, Wiley Periodicals, Inc. 362 application as soft margarines, spreads, fat for bakery/all-purpose shortenings, and icing shortenings, respectively.
Food Research International, 2009
This work evaluated chemical interesterification of canola oil (CaO) and fully hydrogenated cottonseed oil (FHCSO) blends, with 20%, 25%, 30%, 35% and 40% (w/w) FHCSO content. Interesterification produced reduction of trisaturated and increase in monounsaturated and diunsaturated triacylglycerols contents, which caused important changes in temperatures and enthalpies associated with the crystallization and melting thermograms. It was verified reduction in medium crystal diameter in all blends, in addition crystal morphology modification. Crystallization kinetics revealed that crystal formation induction period and maximum solid fat content were altered according to FHCSO content in original blends and as a result of random rearrangement. Changes in Avrami constant (k) and exponent (n) indicated, respectively, that interesterification decreased crystallization rates and altered crystalline morphology. However, X-ray diffraction analyses showed randomization did not change the original crystalline polymorphism. The original and interesterified blends had significant predominance of b 0 polymorph, which is interesting for several food applications.
Grasas y Aceites, 2016
The composition and distribution of fatty acids in triacylglycerol (TAG) molecules are commonly considered as factors that determine the physical properties of a given oil or fat. The distribution of any fatty acid in fats and oils can be described through the α coefficient of asymmetry, which can be calculated from the TAG composition and fatty acid composition of the sn-2 position of the TAGs determined through lipase hydrolysis. High-oleic high-stearic oils and fats are considered stable and healthy, and they are good substitutes for hydrogenated vegetable oils and palm fractions in many food products, such as spreads and confectionery. Here, different high-oleic high-stearic acid oils were formulated which contained different distributions of saturated fatty acids in their TAGs, while maintaining a similar fatty acid composition. The aim of this work was to discuss the possibility of using the α coefficient to predict the physical properties of fats in function of their chemical composition and their melting and crystallization behavior as examined by differential scanning calorimetry.
Journal of The American Oil Chemists Society, 2009
A blend of palm stearin and soybean oil (70/30, wt%) was modified by chemical interesterification (CIE) and enzymatic interesterification (EIE), the latter batch-wise (B-EIE) and in continuous (C-EIE). Better oil quality, mainly in terms of acidity, free tocopherol and partial acylglycerol content, was obtained after EIE. The clear melting point after any interesterification process was similar and about 9 °C lower as result of the modification in the TAG profile, which approaches the calculated random distribution. Interesterification changed the SFC profile significantly. For the fully refined interesterified blends, the SFC profile was similar and clearly different from the starting blend. Interesterification decreased the content of solids at temperatures >15 °C and increased the content of solids at temperatures
Journal of Food Lipids, 2000
Melting characteristics and solid fat content of anhydrous milk fat (AMF), soft palm oil stearin (SPOs), hard palm oil stearin (ffPOs) and their blends were studied by diferential scanning calorimetry (DSC) and nuclear magnetic resonance (NMR) spectroscopy, respectively. Solid fat contents (SFC) determined by NMR were used to construct isosolid diagrams; these indicated the presence of an eutectic effect along the binary blends of AMF:SPOs which only could be observed at 5 and IOC. The effect was reduced after interesterifcation by sn-1,3specific lipase. The modification also reduced the number of the distinct DSC melting peaks, demonstrating a better miscibility among the blended fats. A substantial decrease in DSC melting enthalpy of interesterifed blends was found to be parallel to a decrease in SFC that was observed at 25-4OC. Fatty acid composition showed that improved functionality of AMF may be due to an enrichment in long-chain saturated fatty acidr contributed both by SPOs and HPOs.
Journal of Agricultural and Food Chemistry, 2004
In this study enzymatic-interesterified margarine fats with different conversion degrees were produced in a packed-bed reactor. The effects of conversion degree on the formation of free fatty acids and diacyglycerols, solid fat content, crystallization behavior, microstructure, and crystal network were investigated, and the enzymatically interesterified products were compared with a chemically interesterified product. Formation of free fatty acids and diacyglycerols increased slightly with increasing conversion degree. The solid fat content was higher at 10 and 20 degrees C and lower at 30, 35, and 40 degrees C with increasing conversion degree. Increased conversion degree from the blend to products, measured by X-ray with addition of 50% of rapeseed oil for dilution, caused the content of beta to decrease from 100% to 33%, and 30% and eventually to pure beta' crystal. However, double chain packing was observed for both the blend and products. Isothermal crystallization kinetics was characterized by the Fisher-Turnbull model. The highest free energy was observed for the blend. A small deformation with oscillation tests shows a significant difference between the blend and interesterified products. The differences of microstructure between the blend, different conversion degree, and chemical randomized product were observed.
Effects of chemical interesterification on physicochemical properties of blends of palm stearin and
Palm stearin (PS) and rice bran oil (RBO) were blended in the mass ratio of 100:0, 70:30, 50:50, 30:70 and 0:100. The oil blends were subjected to chemical interesterification (CIE) catalyzed by sodium methoxide (0.2% w/w). The following analysis were carried out before and after CIE: triacylglycerol (TAG) composition, slip melting point (SMP), solid fat content (SFC), microstructure, polymorphism and hardness index (HI). After chemical interesterification, there were decrease and increase in the amount of several TAG. Changes in TAG composition caused changes in the physical properties of the blends. Both SMP and SFC of all blends decreased significantly (p<0.05) after interesterification except for RBO. Chemical interesterification also reduced the eutectic interaction at 5°C. However, for hardness index, only blends with 50% and 100% PS decreased significantly (p<0.05) from 33.197 to 26.097 and 5.397 to 3.720, respectively. The crystals of the blends became smaller and reduced in number after interesterification. Interesterification promoted the formation of more β' crystals than β in all blends. The 30:70 PSRBO blend was the most suitable for margarine production as it melted close to body temperature.