Interesterification Process Research Articles

Enzymatic interesterification effect on the physicochemical and technological properties of cupuassu seed fat and inaja pulp oil blends

The objective of this work was to evaluate the effect of enzymatic interesterification process in blends with different proportions (w:w) of cupuassu fat and inaja oil (80:20, 70:30, 60:40, 50:50 and 40:60). The interesterification reaction was carried out at 65 °C, agitation at 150 rpm, and enzyme concentration of 5% (w/w), for 6 h. Acidity index, melting point, consistency and solid fat content of the blends were characterized before and after the interesterification process. Fatty acid content was characterized in cupuassu fat and inaja oil and, nutritional quality indexes of atherogenicity (AI) and thrombogenicity (TI) were calculated. Enzymatic interesterification promoted a decrease in acidity (<0.6%) and changes in the blends’ properties, making them suitable for food product preparation. All esterified blends (cupuassu seed fat:inaja pulp oil) presented suitable consistency properties, plasticity and spreadability to be used for the preparation of functional, table and soft table types of margarine and used in food preparation such as special fats.

PHYSICOCHEMICAL PROPERTIES OF CHEMICALLY INTERESTERIFIED VEGETABLE OILS

Interesterification is an alternative to partial hydrogenation that helps to manufacture products of a variety of melting properties. When the process is applied to different blends of vegetable oils, redistribution of fatty acids between and within triacyglycerol occurs that changes the physical properties especially the melting characteristics of the vegetable oil blends. For chemical interesterification process, unrefined vegetable oils (soybean oil and cottonseed oils) were obtained from the local industry (United Industries Faisalabad, Pakistan). Different blends of soybean and cottonseed oils were prepared ranging from 100% soybean oil to 100% cottonseed oil in 25% increments (w/w) with different ratios of (100% : 0%, 75% : 25%, 50% : 50%, 25% : 75%, 0% : 100%) respectively. The blended oil portions (500mL) were neutralized and dried. For chemical interesterification sodium methoxide was used as catalyst. At the end of reaction, the catalyst was inactivated and reaction was stopped by the addition of citric acid solution and at the end by the addition of warm water (70-80°C). Interesterified oils were bleached by heating them to 110°C and mixing with bleaching earth and then the hot interesterified oils were filtered and cooled. Physico-chemical properties (refractive index, specific gravity, colour, melting point, free fatty acids, iodine value, peroxide value, saponification value and rancidity) and sensory evaluation (appearance, odor and overall acceptability) of the final product was conducted at 0, 15 and 30 days of interval. The results revealed that refractive index, specific gravity, color, melting point, free fatty acids value, peroxide value and saponification value increased while iodine value decreased with the passage of time. Further studies showed that storage had a highly significant effect on color, melting point, free fatty acids value, iodine value, peroxide value and saponification value. The effect of storage was non-significant for parameters like specific gravity and refractive index.

Mechanistic investigation in ultrasound‐assisted interesterification using non‐edible oil blends and heterogeneous catalyst

AbstractThis study explores the mechanistic issues of ultrasound‐assisted interesterification through identification of links between physics and chemistry of the process. Notably, the interesterification reactions have been carried out using blended feedstock of non‐edible oils—keeping in view requirements for large‐scale processes. The reaction system consisted of blended non‐edible oils, methyl acetate and a solid (Cu2O) catalyst. Initial optimization of the process parameters was done using statistical design. To get insight into physical mechanism of interesterification process, reactants/products profiles in control (mechanical agitation) and test (sonication) experiments were analysed using the Langmuir–Hinshelwood–Hougen–Watson type kinetic model. The relative adsorption equilibrium constants required (to fit the kinetic model) were obtained using binary composite isotherm coupled with the non‐random two‐liquid (NRTL) model for activity coefficients. Kinetic constants of interesterification showed two times rise with sonication, while the adsorption equilibrium constants reduced slightly. Activation energy of reaction reduced from 89.04 to 66.97 kJ/mol, which is attributed to reduction in mass transfer barriers due to intense microconvection generated by sonication.

Modification of palm-based oil blend via interesterification: Physicochemical properties, crystallization behaviors and oxidative stabilities

Interesterification is widely employed as an effective technique to modify oils and fats. This study utilizes palm-based oil (palm olein: palm kernel oil: palm stearin, 5:3:2, w/w/w) as the raw material for the interesterification process performed in a pilot-scale packed bed reactor. Enzymatic interesterification (EIE) was catalyzed by Lipozyme TL IM (813.0 g) at 60℃ with reaction flow rate of 100 mL/min. Chemical interesterification (CIE) was catalyzed using sodium methoxide (0.3 wt%) as catalyst at 105 °C for 30 min. The results showed that the EIE fats had lower solid fat content tendency compared to that of CIE fats. The crystallization onset temperature was higher in EIE fats (23.09℃) compared to that of CIE (19.08℃). The results were consistent with the crystallization kinetics whereby the Avrami K constants of EIE fats were higher than that of CIE fats at various temperatures, indicating rapid crystallization and instant nucleation. Linear growth mechanism was dominant and the crystals formed were smaller in size as observed using polarized light microscope. The interesterified fats exhibited the presence of β and β′-crystals. While most of the tocopherol content was retained after EIE (386.18 ug/g), the molecular distillation process reduced the tocopherol concentration (110.01 ug/g) which consequently affected the oxidative stability. The findings in this work contribute to the fundamental understanding on the differences between CIE and EIE fats and provides data to support the preparation of modified fats via EIE that shows great potential as a controllable technique for industrialization.

Lipase-catalyzed Synthesis of Feruloylated Lysophospholipid in Toluene-Ionic Liquids and Its Antioxidant Activity.

In this study, Novozym 435-catalyzed interesterification of ethyl ferulate (EF) with phosphatidylcholine (PC) in a two-phase system consisting of an ionic liquid (IL) and toluene was optimized to prepare feruloylated lysophospholipids (FLPs). Optimum conditions for the interesterification process were found to be [Bmim][Tf2N]/toluene ratio of 1:1 (v/v), solvent volume of 4 mL, molecular sieves (4 Å) concentration of 80 mg/mL, reaction temperature of 55°C, substrate molar ratio of 5:1 (PC/EF), Novozym 435 concentration of 50 mg/mL. Under these conditions, two FLPs products (1-FLP and 2-FLP) with total conversion rate of 50.79% were obtained. Because the formation of 1-FLP was significantly higher than 2-FLP, 1-FLP was purified and characterized by LC-MS and NMR. In addition, 1-FLP showed DPPH scavenging activity comparable with those of EF and BHT. Therefore, this study provides a good method for transformation of ferulic acid to improve its solubility and promote its application as functional ingredient in the food and pharmaceutical industries.

Zero-trans fats designed by enzyme-catalyzed interesterification of rice bran oil and fully hydrogenated rice bran oil

Zero-trans edible fats attractive to be used for shortenings or margarines were designed solely from rice bran oil (RBO). For this purpose, RBO was fully hydrogenated, blended with the original oil at different percentages, and finally, blends were interesterified by an enzyme-catalyzed process. The interesterification process reduced the concentration of trisaturated and triunsaturated triglycerides and increased the concentration of medium saturation degree molecules, thus increasing their compatibility and causing the moderation of the melting point, as compared with blends. Conversely to blends, products showed a high tendency to crystallize under the β’ polymorph, which is the preferred one for products destined for many edible applications. Results demonstrated that the proper combination of different technologies (total hydrogenation, blending and interesterification) is a versatile and useful technology for designing zero-trans fats from RBO, attractive for the confection of shortenings or margarines for different applications depending on the proportion of each component in the starting blend. This strategy offers an attractive alternative for the diversification of RBO utilization, a valuable vegetable oil still underexploited, providing attractive fats useful for structuring different type of foods.

Some Thoughts on the Mechanism of Ester Interchange Reactions Involving Acylglycerols

AbstractEster interchange reactions involving acylglycerides are industrially important because the interesterification process provides trans‐isomer free hardstocks and the transesterification process produces biodiesel. This Commentary proposes to extend the enolate mechanism that has been suggested for the interesterification process to the transesterification process. It also highlights the gaps in people's knowledge and discusses the implication of these gaps.Practical Applications: Insight into the mechanism of the interesterification reaction provides means to eliminate the yield loss suffered by the current industrial processes. Use of an alkali metal glycerolate will avoid the formation of fatty acid methyl esters and their subsequent loss. Using the same catalyst during the transesterification will reduce the variable cost of this process since this catalyst can be easily produced on site from by‐product glycerol.

Synthesis and characterization of structured lipid rich in behenic acid by enzymatic interesterification

Enzymatic interesterification has the advantage of promoting great control over the positional distribution of fatty acids in the final product. However, the difficulties associated with process control and scaling-up have reduced its industrial use as a catalyst for lipid modification. Thus, the objective of this work was to scale-up production and to evaluate the physic-chemical properties of a structured lipid (SL) based on soybean, olive and fully hydrogenated crambe oils obtained by an enzymatic interesterification process. Enzyme conditioning promoted low concentration of free fatty acids in the SL and the rearrangement of trisaturated triacylglycerols was completed after a reaction time of 4h. The scaling-up did not reproduce exactly the same physicochemical modifications previously observed in SL obtained in a benchscale, but the process of obtaining the SL was controlled and showed low variation of the acidity indexes, triacylglycerol composition, regiospecificity and crystallization profile, and the levels of tocopherols, chlorophyll and oxidative stability did not altered. Thus, it was possible to upscale the SL production by 50 times, with modifications in its physico-chemical properties due to differences in lipase activity.

Production of feruloylated lysophospholipids via a one-step enzymatic interesterification

Incorporation of ferulic acid (FA) into egg-yolk phosphatidylcholine (PC) in a lipase-catalyzed acidolysis and interesterification process was studied using four commercially available immobilized lipases as catalysts and two acyl donors: ferulic acid (FA) and ethyl ferulate (EF). Novozym 435 and a binary solvent system of toluene/chloroform 9:1 (v/v) were found to be the most suitable biocatalyst and medium, respectively, and significantly increased the incorporation of FA into the phospholipid fraction. Subsequently response surface methodology (RSM) and Box-Behnken design were employed to evaluate the effects of substrate molar ratio, enzyme loading and time of the reaction on the process of interesterification. The selected optimized parameters were established as PC/EF molar ratio 1/15, enzyme load 30% (w/w) and incubation time 6 days. The process of interesterification at the optimized parameters carried out on a large scale afforded feruloylated lysophosphatidylcholine (FLPC) in high isolated yield of 62% (w/w).

Synthesis of renewable heterogeneous acid catalyst from oil palm empty fruit bunch for glycerol-free biodiesel production

Interest in biodiesel research has escalated over the years due to dwindling fossil fuel reserves. The implementation of a carbon-based solid acid catalyst in biodiesel production eradicates the separation problems associated with homogeneous catalysis. However, its application in the glycerol-free interesterification process for biodiesel production is still rarely being studied in the literature. In this study, novel environmentally benign catalysts were prepared from oil palm empty fruit bunch (OPEFB) derived activated carbon (AC) which is sustainable and low cost via direct sulfonation using concentrated sulfuric acid. The effects of synthesizing variables such as carbonization and sulfonation temperatures with different holding times towards the fatty acid methyl ester (FAME) yield in interesterification reaction with oleic acid and methyl acetate were investigated in detail. It was found that the optimum carbonization temperature and duration together with sulfonation temperature and duration were 600 °C, 3 h, 100 °C and 6 h, respectively. The catalyst possessed an amorphous structure with a high total acid density of 9.0 mmol NaOH g−1 due to the well-developed porous framework structure of the carbon support. Under these optimum conditions, the OPEFB derived solid acid catalyst recorded an excellent catalytic activity of 50.5% methyl oleate yield at 100 °C after 8 h with 50:1 methyl acetate to oleic acid molar ratio and 10 wt% catalyst dosage. The heterogeneous acid catalyst derived from OPEFB had shown promising properties that made them highly suitable for cost-effective and environmental-friendly glycerol-free biodiesel production.

Interesterification of a commonly consumed palm-based hard fat blend does not affect postprandial lipoprotein metabolism in healthy older adults

AbstractInteresterified (IE) fats are widely used to replace partially-hydrogenated fats as hard fats with functional and sensory properties needed for spreads/margarines, baked goods, and confectionary, while avoiding the health hazards of trans fats. Detailed mechanistic work to determine the metabolic effects of interesterification of commonly-consumed hard fats has not yet been done. Earlier studies using fats less commonly consumed have shown either neutral or a lowering effect on postprandial lipaemia. We investigated postprandial lipaemia, lipoprotein remodelling, and triacylglycerol-rich lipoprotein (TRL) fraction apolipoprotein concentrations following a common IE blend of palm oil/kernel fractions versus its non-IE counterpart, alongside a reference monounsaturated (MUFA) oil. A 3-armed, double blind, randomized controlled trial (clinicaltrials.gov NCT03191513) in healthy adults (n = 20; 10 men, 10 women) aged 45–75 y, assessed effects of single meals (897 kcal, 50 g fat, 16 g protein, 88 g carbohydrate) on postprandial plasma triacylglycerol (TAG) concentrations, lipoprotein profiles, and TRL fraction apolipoprotein B48 and TAG concentrations. Test fats were IE 80:20 palm stearin/palm kernel fat, the equivalent non-IE fat, and a high-MUFA reference oil (rapeseed oil, RO). Blood was collected at baseline and hourly for 8 h. Linear mixed modelling was performed, adjusting for treatment order and baseline values (ver. 24.0; SPSS Inc., Chicago, IL, USA). Total 8 h incremental area under the curves (iAUC) for plasma TAG concentrations were lower following IE and non-IE compared with RO (mean difference in iAUC: non-IE vs. RO -1.8 mmol/L.h (95% CI -3.3, -0.2); IE vs. RO -2.6 mmol/L.h (95% CI -5.3, 0.0)), but iAUCs for IE and non-IE were not significantly different. There were no differences between IE and non-IE for chylomicron fraction apoB48 concentrations nor TAG:apoB48 ratio. No differences were observed between IE and non-IE for lipoprotein (VLDL, HDL, LDL) particle size or sub-class particle concentrations. However, LDL particle diameters were reduced at 5 and 6 h following IE vs RO (P &lt; 0.05). XXL- (including chylomicron remnants and VLDL particles), XL- and L-VLDL particle concentrations (average diameters &gt; 75, 64, and 53.6 nm respectively) were higher following IE and non-IE vs. RO at 6 h (P &lt; 0.05) and 8 h postprandially (P &lt; 0.005–0.05). In conclusion, both IE and non-IE palmitic acid-rich fats generated a greater preponderance of pro-atherogenic large TRL remnant particles in the late postprandial phase relative to an oleic acid-rich oil. However, the process of interesterification did not modify postprandial TAG response or lipoprotein metabolism.

Zero-trans fats by enzymatic interesterification of blends beef tallow / rice bran oil

The aim of this study was to analyze in detail the changes produced by the enzymatic interesterification of BT/RBO blends (beef tallow/rice bran oil) at different proportions, as an alternative for production of trans free fats. It was observed that the increase in the oil content produced a range of the content of saturated fatty acids from 20 to 38% in the blend and a range of polyunsaturated fatty acids from 35 to 18%. In TAG composition, the SUU and SSS type (S: saturated fatty acid; U: unsaturated fatty acid) increased in concentration as a result of interesterification process and this effect was more noticeable when the blend was richer in oil, arriving at 19 and 4% respectively in 50:50 BT/RBO blend. These variations in composition greatly improved the plastic range of BT. The process studied produced new trans free fatty materials with improving suitability as food ingredients. Therefore, promising new materials were developed.

Biodiesel fuel synthesis by interesterification of triglycerides with carboxylate esters of low molecular weight

Abstract The ever-increasing environmental pollution from greenhouse gases motivates the search for methods to reduce it. One such method is the use of biodiesel fuels in the transport sector. Conventional biodiesel production generates up to 10% of a by-product, raw glycerol, whose amount continues to increase as biodiesel production volumes expand, but its demand remains limited. Recently, options have been analysed to replace the triglyceride transesterification process generally used in biodiesel production with an interesterification process that does not generate raw glycerol, instead yielding triacylglycerol that can be directly used as fuel for diesel engines by mixing with fatty acid esters. Additionally, triacylglycerol improves the low-temperature properties of fuel. The present article discusses triglyceride interesterification processes using various carboxylate esters of low molecular weight. Information is provided on raw materials that can be subjected to interesterification for biodiesel synthesis. The possible applications of chemical and enzymatic catalysis for triglyceride interesterification are discussed, and the influence of the catalyst amount, molar ratio of reactants, temperature and process duration on the effectiveness of interesterification is examined. The conditions and effectiveness of noncatalytic interesterification are also discussed in the article. Qualitative indicators of the products obtained and their conformity to the requirements of the European standard for biodiesel fuel are discussed.

Formation of by-products during chemical interesterification of lipids. Detection and characterization of dialkyl ketones by non-aqueous reversed-phase liquid chromatography-high resolution mass spectrometry and gas chromatography-mass spectrometry

A new class of foreign substances present in the unsaponifiable fraction of vegetable oils undergone to chemical interesterification was systematically investigated. Their chemical structure, corresponding to dialkyl ketones (DAK) molecules, was elucidated both by gas chromatography-mass spectrometry (GC–MS), and liquid chromatography-high resolution mass spectrometry (LC-HRMS). An analytical protocol aimed to qualitative and quantitative detection of DAK molecules in vegetable oils of confectionery industry interest was developed. Being the range of concentration levels to be evaluated dependent on the technological task of interesterification process, the quantitation step was thoroughly examined. All the validation parameters were satisfactory and particularly the concentration determinations were made more reliable by the contemporary use of several quantitation standards. GC–MS and LC-HRMS analytical techniques exhibited comparable performances even if the second one shown better detection sensitivity.

Catalytic Properties of Lipase Entrapped as Lysates of Recombinant Strain-Producer rEscherichia coli/lip into Nanocarbon-in-Silica Composites in the Bioconversion of Triglycerides and Fatty Acids

Composite multi-component biocatalysts were prepared by entrapping lysates of a recombinant rE. coli/lip strain producing Thermomyces lanuginosus lipase into composite nanocarbon-containing matrices based on a SiO2 xerogel. The dependence of the lipase activity and operational stability on the type of the carbon component (nanotubes or nanospheres of different diameters) was studied in the bioconversion of triglycerides (hydrolysis and interesterification), as well as in the esterification of saturated fatty acids—namely, butyric (C4:0), capric (C10:0), and stearic (C18:0) acids—with isoamyl alcohol. It was shown that the biocatalytic properties were determined by both the texture parameters of the nanostructured carbon included and the type of enzymatic reaction performed. Biocatalysts without a nanocarbon component had the highest operational stability in the batch process of interesterification of sunflower oil with ethyl acetate; the half-life time was found to be 720 h at 40°C. Biocatalysts containing carbon nanotubes of ~21 nm in diameter were five to six times more active in the batch esterification process than biocatalysts without a nanocarbon component. Biocatalysts containing carbon nanotubes catalyzed the synthesis of esters in a binary organic solvent (hexane and diethyl ether) without a loss of activity for more than 500 h at 40°C.

Effects of Chocolates Using Low Calorie Cocoa Butter Substitutes on Rat’s Plasma Profile and Determination of Sn-1,3 Position

The present study sought to determine the effectiveness of newly developed low calorie chocolate using modified fat through enzymatic interesterification process as cocoa butter substitute of male Sprague Dawley rats (n = 35) compared to cocoa butter as control. Body weight gains did not differ significantly (p&gt;0.05) in all the test groups fed with chocolates which were using different types of fats. Triacylglycerol and cholesterol test showed no significant difference (p&gt;0.05) for all treatment samples. in this study, a pancreatic lipase hydrolysis was performed to determine the fatty acid composition of the sn-2 position of the structure lipids.

Isolation, Characterization, and Production of Lipase from Indigenous Fungal for Enzymatic Interesterification Process

Lipase catalyses hydrolysis and esterification of lipids. The purpose of this research was to obtain lipase producing indigenous fungi, to identify the selected fungi, to study optimum temperature and pH of the enzyme activity, as well as the enzyme ability in interesterification reaction. The isolates used in the experiment were isolated from tempeh, oncom and BPPT laboratory culture collection. The results showed that three fungal isolates which isolated, tempe and oncom and an isolate of BPPT-CC were positive produced lipase after qualitative assay using Rhodamine B, olive oil and PVA. The morphology identification of the isolates, revealed that R isolate was Aspergillus sp, T isolate was Neurospora sp. and O isolate was Rhizopus sp. Upon quantitative assay from determination of the media and time production, potato dextro broth (PDB) with olive oil 2% in 48 hours fermentation showed the highest specific activity of the enzymes. Lipase produced from three isolate have the optimum at pH 4, temperatures at 40-45 °C and stable in interesterification reaction (55 °C) for 30-40 min. HPLC analysis after interesterification enzymatic reaction in mixture palm kernel olein (PKOo) and palm stearin (POs) showed that the composition of triglycerides (TAG) do not change if compared with the commercial lipase (Lypozyme TL1M).

Enzymatic modification of egg lecithin to improve properties.

This research studied the enzymatic modification of egg yolk phospholipids and its effect on physicochemical properties. Egg yolk lipids were extracted with food grade ethanol and egg phospholipids (ePL) produced by deoiling with acetone. Vegetable oils were used to interesterify ePL utilizing Lipozyme®: sn-1,3 specific lipase. The enzymatic interesterification resulted in a single phase liquid product, whereas simple blending of the ePL and vegetable oil resulted in a product with two phases. In addition solid fat content decreased by 50% at -10°C and 94% at 35°C when compared with egg yolk lipids extract. A decrease in melting temperature resulted from the interesterification process. Interesterification improved emulsion stability index when used as an emulsifier in oil-in-water emulsion and compared to the native and soy lecithin. Enzyme reusability test showed retention of 63% activity after 10 cycles. Overall, the properties of native egg phospholipids were significantly enhanced in a potentially useful manner through interesterification.

Chemical interesterification of blends with palm stearin and patawa oil

The present study sought to develop lipid bases from blends between patawa oil and palm stearin. These blends were analyzed before and after the chemical interesterification process for their fatty acid and triacylglycerol composition, free fatty acid (FFA) content, peroxide index, thermal properties, melting point, consistency, and solid fat content (SFC). Blends with unsaturated fatty acid contents between 60 and 70% were obtained, with a good ratio between saturated and unsaturated fatty acids, which indicates a healthy content of fatty acids. Variations in the triacylglycerol contents and melting and crystallization thermograms evidenced the reaction. The blend with 50% stearin and 50% patawa oil showed the best results after the chemical interesterification reaction regarding the possible application in fatty products for its appropriate melting point, SFC similar to that of soft table margarines, plastic and spreadable consistency at refrigeration temperature, thus combining physical and nutritional properties desirable for the food industry.

A study of fat interesterification parameters’ effect on the catalytic reaction activity of potassium glycerate

The study has disclosed the peculiarities of the interesterification process in the presence of potassium glycerate as the catalyst. The properties of palm olein as a result of interesterification have been found to depend on such parameters as temperature, duration, and catalyst concentration. The study makes use of a central composite design (CCD) of the second order orthogonal plan. The melting temperature of palm olein is accepted as a response function. The initial palm olein and the samples obtained according to the plan of the experiment were researched by differential scanning calorimetry to determine the characteristics of the phase transitions – melting and crystallization. The biggest difference was observed between the melting temperatures in a capillary and the temperature peaks on the curves of DSC thermograms for highly­fusible samples; the peak temperature in the DSC thermogram exceeds in these cases the temperature determined in the capillary. The study has revealed that the maximum melting temperature of palm olein occurs during the interesterification process at a temperature of 100 °C, with the process duration of 1.5 hours, and with the catalyst concentration of 0.5 %. The temperature difference between the initial melting and the interesterified palm olein was observed as exceeding 12 °C when the catalyst concentration, most often used in interesterification, was 0.1 %, at a temperature of 100 °C, and with the process duration of 1.5 hours.