Underutilised palm stearin as hard stock for deep-frying medium and its performance for oil uptake in instant noodles.

BACKGROUND: As a by-product of the palm oil industry, palm stearin is often overlooked despite having several beneficial properties, such as excellent stability, which is critically essential to meet the demand of the global food trend in producing safer processed food. Specifically, deep frying of food is often associated with the production of toxic compounds that could potentially migrate into the food system when oils are degraded under continuous heating. The incorporation of palm stearin is regarded as a cost-effective and efficient method to modify the fatty acid composition of oils, enhance the frying qualities and lower the degradation rate. RESULTS: This study blended 5% and 10% palm stearin into palm oil to investigate the deep-frying performance and impact on food quality. Increasing the palm stearin content improved the frying oil's oxidative and hydrolytic stability, evidenced by reduction of total polar material, free fatty acid and total oxidation value. Addition of palm stearin increased the slip melting point which improved the oil's oxidative stability but no significant increase in oil content of instant noodles was observed. Scanning electron microscopy and fluorescence microscopy showed the formation of larger pores in the noodle structure that facilitated oil retention. CONCLUSION: Blending palm stearin into frying oil enhanced the frying stability and minimally affected the oil uptake in instant noodles. This article presents the viability of blending palm stearin into frying oils to develop longer-lasting frying oils. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Synthesis of cocoa butter alternatives from palm kernel stearin, coconut oil and fully hydrogenated palm stearin blends by chemical interesterification.

BACKGROUND: Chemical interesterification (CIE) is one of the important technological processes for the production of zero-trans fats. The aim of this study was to produce trans-free cocoa butter alternatives (CBAs) from palm kernel stearin (PKS), coconut oil (CNO) and fully-hydrogenated palm stearin (FHPS) blends via CIE using sodium methoxide as a catalyst. The physicochemical properties, crystallization and melting behavior, solid fat content (SFC), crystal morphology and polymorphism of the structured lipids (SLs) obtained and the corresponding physical blends (PBs) were characterized and compared with commercial CBAs. RESULTS: After CIE, randomization of fatty acid distribution within and among triacylglycerol (TAG) molecules of PKS, CNO and FHPS resulted in a modification in TAG compositions of the PKS/CNO/FHPS blends and improved the properties and crystallization behavior of the blends. SFC and slip melting points of all SLs decreased from those of their respective PBs. In particular, SLs obtained from CIE of blends with 60-70% wt. PKS (blend ratios 60:10:30 and 70:10:20) exhibited the melting characteristic, SFC curves, crystal morphology and polymorphic form most similar to the commercial CBAs. In addition, these blends melted almost completely at body temperature, an improvement from that of the commercial CBAs. CONCLUSION: SLs obtained from CIE of blends with 60-70% wt. PKS has high potential to be used commercially as trans-free CBAs for the confectionery industry. © 2021 Society of Chemical Industry.

Addition of glyceryl monostearate affects the crystallization behavior and polymorphism of palm stearin.

Low crystallization-rate and formation of crystalline clusters makes palm stearin unpopular in fat-based products especially in their post-processing stage. Addition of emulsifiers is commonly used to overcome these drawbacks, since they are believed to induce or stabilize specific polymorphs of palm stearin. Glyceryl monostearate (GMS) was applied in palm stearin (1%, 2%, and 4% w/w) in this study, and the mechanisms on crystallization of palm stearin were investigated by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD), and polarized light microscopic (PLM) method. Data showed that GMS prompted the isothermal crystallization (15-30 °C) in a dose-dependent manner. Crystallization turned to low super-cooling sporadic nucleation at 30 °C. Besides, GMS led to an earlier onset of crystallization during cooling. GMS-palm stearin blends crystallized to form α polymorphs at first and subsequently underwent polymorphic transition to become ß' polymorphs. Addition of 4% w/w GMS in palm stearin significantly decreased the size of crystals, which is helpful to reduce the grainy mouth feel of fat products in practice.

Preparation of Low-Diacylglycerol Cocoa Butter Equivalents by Hexane Fractionation of Palm Stearin and Shea Butter.

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.

Modulation of postprandial lipaemia by a single meal containing a commonly consumed interesterified palmitic acid-rich fat blend compared to a non-interesterified equivalent.

PURPOSE: Interesterification of palm stearin and palm kernal (PSt/PK) is widely used by the food industry to create fats with desirable functional characteristics for applications in spreads and bakery products, negating the need for trans fatty acids. Previous studies have reported reduced postprandial lipaemia, an independent risk factor for CVD, following interesterified (IE) palmitic and stearic acid-rich fats that are not currently widely used by the food industry. The current study investigates the effect of the most commonly consumed PSt/PK IE blend on postprandial lipaemia. METHODS: A randomised, controlled, crossover (1 week washout) double-blind design study (n = 12 healthy males, 18-45 years), compared the postprandial (0-4 h) effects of meals containing 50 g fat [PSt/PK (80:20); IE vs. non-IE] on changes in plasma triacylglycerol (TAG), glucose, glucose-dependent insulinotropic polypeptide (GIP), peptide YY (PYY), insulin, gastric emptying (paracetamol concentrations) and satiety (visual analogue scales). RESULTS: The postprandial increase in plasma TAG was higher following the IE PSt/PK versus the non-IE PSt/PK, with a 51 % greater incremental area under the curve [mean difference with 95 % CI 41 (23, 58) mmol/L min P = 0.001]. The pattern of lipaemia was different between meals; at 4-h plasma TAG concentrations declined following the IE fat but continued to rise following the non-IE fat. Insulin, glucose, paracetamol, PYY and GIP concentrations increased significantly after the test meals (time effect; P < 0.001 for all), but did not differ between test meals. Feelings of fullness were higher following the non-IE PSt/PK meal (diet effect; P = 0.034). No other significant differences were noted. CONCLUSIONS: Interesterification of PSt/PK increases early phase postprandial lipaemia (0-4 h); however, further investigation during the late postprandial phase (4-8 h) is warranted to determine the rate of return to baseline values. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov as NCT02365987.

Physico-chemical properties of Moringa oleifera seed oil enzymatically interesterified with palm stearin and palm kernel oil and its potential application in food.

BACKGROUND: High oleic acid Moringa oleifera seed oil (MoO) has been rarely applied in food products due to the low melting point and lack of plasticity. Enzymatic interesterification (EIE) of MoO with palm stearin (PS) and palm kernel oil (PKO) could yield harder fat stocks that may impart desirable nutritional and physical properties. RESULTS: Blends of MoO and PS or PKO were examined for triacylglycerol (TAG) composition, thermal properties and solid fat content (SFC). EIE caused rearrangement of TAGs, reduction of U3 and increase of U2 S in MoO/PS blends while reduction of U3 and S3 following increase of S2 U and U2 S in MoO/PKO blends (U, unsaturated and S, saturated fatty acids). SFC measurements revealed a wide range of plasticity, enhancements of spreadability, mouthfeel and cooling effect for interesterified MoO/PS, indicating the possible application of these blends in margarines. However, interesterified MoO/PKO was not suitable in margarine application, while ice-cream may be formulated from these blends. A soft margarine formulated from MoO/PS 70:30 revealed high oxidative stability during 8 weeks storage with no significant changes in peroxide and p-anisidine values. CONCLUSION: EIE of fats with MoO allowed nutritional and oxidative stable plastic fats to be obtained, suitable for possible use in industrial food applications. © 2015 Society of Chemical Industry.

Preparation of human milk fat analogue by enzymatic interesterification reaction using palm stearin and fish oil.

Palm stearin fractionate (PSF), obtained from palm stearin by further fractionation with solvents and n-3 polyunsaturated fatty acids (n-3 PUFA) rich fish oil (FO) were subjected to interesterification at 1:1, 1:2, 1:3, 2:1 and 3:1 substrate molar ratio and catalyzed by lipase from Thermomyces lanuginosa for obtaining a product with triacylglycerol (TAG) structure similar to that of human milk fat (HMF). The parameters (molar ratio and time) of the interesterification reaction were standardized. The temperature of 60 °C and enzyme concentration of 10 % (w/w) were kept fixed as these parameters were previously optimized. The reactions were carried out in a stirred tank reactor equipped with a magnetic stirrer for 6, 12, 18 and 24 h. The blends were analyzed for fatty acid (FA) composition of both total FAs and those at the sn-2 position after pancreatic lipase hydrolysis. All the blended products were subjected to melting point determination and free fatty acid content. Finally, blend of PSF and FO at 2:1 molar ratio with 69.70 % palmitic acid (PA) content and 12 h of reaction produced the desired product with 75.98 % of PA at sn-2 position, 0.27 % arachidonic acid (AA), 3.43 % eicosapentaenoic acid (EPA) and 4.25 % docosahexaenoic acid (DHA) and with melting point of 42 °C. This study portrayed a successful preparation of TAG containing unique FA composition i.e. ≥ 70 % of the PA, by weight, were esterified at the sn-2 position which could be used in infant formulation with health benefits of n-3 PUFAs.

Effect of palm stearin on the physicochemical characterization and capsaicinoid digestion of Sichuan hotpot oil.

Beef tallow (BT) is the common hotpot oil used in Sichuan hotpot, increasing its characteristic flavors and making it taste better. However, the cholesterol content in BT is high, which may induce cardiovascular diseases. In this study, the effect of palm stearin (PS) on Sichuan hotpot oil was evaluated. The PS: BT blends showed similar physicochemical properties to BT from the results of sensory evaluation, pulsed NMR, DSC, and polar light micrograph (PLM). Furthermore, since spiciness is the essential characteristic of Sichuan hotpot, the digestive properties of capsaicinoids in hotpot oil were used as an evaluation index. The results showed that the digestive properties of capsaicinoids in hotpot oil containing PS were consistent with those without PS. In conclusion, PS can be partially used to replace BT, which can broaden the types of oil used for hotpot and help develop a new hotpot oil.

Balancing functional and health benefits of food products formulated with palm oil as oil sources.

Palm oil (PO) is widely utilised in the food industry and consumed in large quantities by humans. Owing to its bioactive components, such as fatty acids, carotenoids, vitamin E, and phenolic compounds, PO has been utilised for generations. However, public concern about their adverse effects on human health is growing. A literature search was conducted to identify fractionated palm oil processing techniques, proof of their health advantages, and potential food applications. Refined palm oil (RPO) is made from crude palm oil (CPO) and can be fractionated into palm olein (POl) and palm stearin (PS). Fractional crystallisation, dry fractionation, and solvent fractionation are the three basic fractionation procedures used in the PO industry. The composition of triacylglycerols and fatty acids in refined and fractionated palm oil and other vegetable oils is compared to elucidate the triacylglycerols and fatty acids that may be important in product development. It is well proven that RPO, POl, and PS extends the oil's shelf life in the food business. These oils have a more significant saturated fat content and antioxidant compounds than some vegetable oils, such as olive and coconut oils, making them more stable. Palm olein and stearin are also superior shortening agents and frying mediums for baking goods and meals. Furthermore, when ingested modestly daily, palm oils, especially RPO and POl, provide health benefits such as cardioprotective, antidiabetic, anti-inflammatory, and antithrombotic effects. Opportunities exist for fractionated palm oil to become a fat substitute; however, nutrition aspects need to be considered in further developing the market.

Novel bioactive nanoparticles from crude palm oil and its fractions as foodstuff ingredients.

Novel bioactive nanoparticles derived from crude palm oil (CPO), palm olein, and palm stearin for use in foodstuff products were produced, and their physicochemical characteristics and stability were evaluated. The nanoparticles were prepared by homogenization, using biodegradable casein or gum arabic as an encapsulating material. The encapsulation efficiency (EE), morphology, long-term stability, particle size, polydispersity index, zeta potential, pH, apparent viscosity, color parameters, total carotenoids, and antioxidant activity were determined. All nanoparticles methods produced spherical nanoparticles with EE higher than 85%. Highly homogeneous small particles (<300 nm) showing a tendency toward a yellow color were observed after 60 days of storage at 4 °C. The nanoparticles showed a carotenoid retention index higher than 40% and an antioxidant activity higher than 1,000 µM Trolox/g oil. The bioactive nanoparticles retained the carotenoids and are proposed as a green innovative product to replace synthetic colorants and antioxidants in foodstuffs.

Bioaccessibility and antioxidant activity of ß-carotene loaded nanostructured lipid carrier (NLC) from binary mixtures of palm stearin and palm olein.

ß-carotene (ßC) is an essential nutrient for health. It is a potent antioxidant, anti-cancer, and anti-inflammatory substance. However, ßC has high hydrophobicity property, indicating a low absorption level in the digestive tract. The bioavailability of ßC is reasonably low. Lipid-based delivery systems such as nanostructured lipid carriers (NLC) potentially can help to overcome this problem. This research evaluated the bioaccessibility of the nanostructured mixture of palm stearin (PS) and palm olein (PO) and the antioxidant activity of ßC in the structure. ß-carotene bioaccessibility was studied by measuring the micellization during in vitro digestion. Antioxidants activity was measured by 2.2'-azino-bis (3-ethylbenzothiazoline- 6-sulphonic acid) (ABTS) and 2, 2 - diphenyl -1- picrylhydrazyl (DPPH) reduction methods. In vitro gastrointestinal digestion model indicated that nanostructured lipid carrier enhanced bioaccessibility and antioxidants activity of ßC. This suggests that the formulated NLC system can be used effectively to deliver lipophilic bioactive such as ßC in beverage products.

Production of Cocoa Butter Substitute via Enzymatic Interesterification of Fully Hydrogenated Palm Kernel Oil, Coconut Oil and Fully Hydrogenated Palm Stearin Blends.

This research synthesized structure lipids (SL) from blends of fully hydrogenated palm kernel oil (FHPKO), coconut oil (CNO) and fully hydrogenated palm stearin (FHPS) by enzymatic interesterification (EIE)using rProROL, an sn-1,3-specific lipase from Rhizopus oryzae, as a catalyst. Five physical blends of FHPKO:CNO:FHPS were prepared with the following wt. ratios: 40:10:50, 50:10:40, 60:10:30, 70:10:20 and 80:10:10. The EIE reactions were carried out at 60℃ for 6 h in a batch-type reactor using rProROL 10% wt. of the substrate. It was found that EIE significantly modified the triacylglycerol compositions of the fat blends resulting in changes in the crystallization and melting behavior. In particular, SL obtained from EIE of blend 70:10:20 exhibited high potential to be used as a cocoa butter substitute (CBS) because it showed similar solid fat content curve to the commercial CBS and crystallized into fine spherulites and desirable ß' polymorph.

Synergistic Effect of Maleated Natural Rubber and Modified Palm Stearin as Dual Compatibilizers in Composites based on Natural Rubber and Halloysite Nanotubes.

The performance of rubber composite relies on the compatibility between rubber and filler. This is specifically of concern when preparing composites with very different polarities of the rubber matrix and the filler. However, a suitable compatibilizer can mediate the interactions. In this study, composites of natural rubber (NR) with halloysite nanotubes (HNT) were prepared with maleated natural rubber (MNR) and modified palm stearin (MPS) as dual compatibilizers. The MPS dose ranged within 0.5-1.5 phr, while the MNR dose was fixed at 10 phr in all formulations. It was found that the mixed MNR/MPS significantly enhanced modulus, tensile strength, and tear strength of the composites. The improvements were mainly due to improved rubber-HNT interactions arising from hydrogen bonds formed in the presence of these two compatibilizers. This was clearly verified by observing the Payne effect. Apart from that, the MPS also acted as a plasticizer to provide improved dispersion of HNT. It was clearly demonstrated that MNR and MPS as dual compatibilizers improved rubber-HNT interactions and reduced filler-filler interactions, which then improved tensile and tear strengths, as well as dynamical properties. Therefore, the mix of MNR and MPS had a great potential to compatibilize non-polar rubber with HNT filler.

Production of Trans-free fats by chemical interesterified blends of palm stearin and sunflower oil.

In this study, production of trans-free fats through chemical interesterification of binary blends of palm stearin (PS) and sunflower oil (SFO) and their physicochemical changes after the process was investigated. Analyzed responses included fatty acid and triacylglycerol composition, iodine value, free fatty acid (FFA), soap content, peroxide value (PV), plastic range, slip melting point (SMP), solid fat content (SFC), and oxidative stability along with potential applications of the interesterified fats. Transfatty acid content of PS/SFO blends was lower than 0.36%. Chemical interesterification increased the FFA and soap content and also decreased PV and oxidative stability index (at 110°C). After the process, SMP and SFC were reduced, also the plastic range transferred to the lower temperatures. All the interesterified blends melted completely at the body temperature, and their SFC was <32%. The melting characteristics of the PS/SFO-interesterified blends were suitable for many fat-based products.

Enzymatic glycerolysis-interesterification of palm stearin-olein blend for synthesis structured lipid containing high mono- and diacylglycerol.

The objective of this research was to evaluate enzymatic glycerolysis-interesterification to synthesize structured lipids (SLs) containing high monoacylglycerol (MAG) and diacylglycerol (DAG) from a palm stearin-olein blend (PS-PO blend). The results showed that the optimum conditions for the solvent to fat ratio, glycerol to fat ratio, and enzyme concentration were 2:1 (v/w), 1.5:1, and 15% (w/w), respectively. The conversion rate of MAG and DAG decreased at a high glycerol to fat ratio, low solvent to fat ratio, and high enzyme concentration due to an increase in viscosity and low agitation effectiveness. The emulsion capacity and stability of the SLs were 60.19% and 96.80%, respectively. The hardness of the SLs increased about 3.1-fold. The MAG, DAG, and triacylglycerol conversion rates were 0.45, 0.48, and 1.02%/h, respectively. Thus, glycerolysis-interesterification of a PS-PO blend increased DAG and MAG concentrations and further improved the hardness, emulsion capacity, and emulsion stability of the SLs.

Effect of Palm Stearin Oil (PSO), Physical Fractionation Oil of Palm Stearin Oil (PPP) and Structured Lipids of Rich 1,3-Dioleoyl-2-palmitoylglycerol (OPO)on the Stability in Different Emulsion Systems.

This manuscript described the preparation of triglycerides with palmitic and ethyl oleate chains, and the stability of emulsions prepared from those triglycerides. Results showed that ratios of total saturated fatty acids (ΣSFA) of palm stearin oil (PSO), physical fractionation oil of palm stearin oil (PPP) and structured lipids of rich 1,3-dioleoyl-2-palmitoylglycerol (OPO) were 72.5%, 95.4% and 33.2% respectively. Rich 1,3-dioleoyl-2 palmitoylglycerol-emulsion (OPO-E) showed a better emulsion stability than that of palm stearin oil (PSO) and physical fractionation oil of palm stearin oil (PPP). The emulsion stability of OPO-E with 10% structured lipids of rich 1,3-dioleoyl-2-palmitoylglycerol (OPO) showed the highest value compared with 5% and 20% OPO. The value of emulsion stability (ES) was 85.5, the values of volume-surface mean diameter(d32) and weight mean diameter(d43) were 0.09-0.79 µm and 1.1-34.1 µm, respectively. The experimental data had significant (p < 0.05) difference with other emulsions. The value of zeta potential ranged from -34.8 to -53.1 mV, indicating that the emulsion stability of 10% OPO was the most stable in all experiment samples.

Visualized phase behavior of binary blends of coconut oil and palm stearin.

The graded blends of coconut oil (CNO) and palm stearin (POs) phase behavior was studied in the present work, by using pulsed nuclear magnetic resonance (p-NMR), differential scanning calorimetry (DSC) and X-ray scattering (XRD). The kinetic phase diagram which was fitting to DSC data by polynomial equation (R > 0.95), indicated that the CNO-POs binary blends displayed monotectic behavior. The CNO-POs binary system displayed immiscible solid structures (ß and ß' polymorphism) with the addition of POs in the range of 10-60%, beyond which it showed miscible solid structures (ß polymorphism), respectively. Moreover, the presence of POs could elevate the liquid phase transition temperature and transform ß' polymorph into ß. These variations in phase behavior were reflected in the morphology of the binary blends. Our findings not only broaden the application of CNO and POs with novel attributes, but also direct the production of high quality non-hydrogenated fat-containing products.

Dynamics of Polymorphic Transformations in Palm Oil, Palm Stearin and Palm Kernel Oil Characterized by Coupled Powder XRD-DSC.

The in situ polymorphic forms and thermal transitions of refined, bleached and deodorized palm oil (RBDPO), palm stearin (RBDPS) and palm kernel oil (RBDPKO) were investigated using coupled X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results indicated that the DSC onset crystallisation temperature of RBDPO was at 22.6°C, with a single reflection at 4.2Å started to appear from 23.4 to 17.1°C, and were followed by two prominent exothermic peaks at 20.1°C and 8.5°C respectively. Further cooling to -40°C leads to the further formation of a ß'polymorph. Upon heating, a of ß'→ßtransformation was observed between 32.1 to 40.8°C, before the sample was completely melted at 43.0°C. The crystallization onset temperature of RBDPS was 44.1°C, with the appearance of the α polymorph at the same temperature as the appearance of the first sharp DSC exothermic peak. This quickly changed from α→ߴ in the range 25 to 21.7°C, along with the formation of a small ß peak at -40°C. Upon heating, a small XRD peak for the ß polymorph was observed between 32.2 to 36.0°C, becoming a mixture of (ß´+ ß) between 44.0 to 52.5°C. Only the ß polymorph survived further heating to 59.8°C. For RBDPKO, the crystallization onset temperature was 11.6°C, with the formation of a single sharp exothermic peak at 6.5°C corresponding to the ß' polymorphic form until the temperature reached -40°C. No transformation of the polymorphic form was observed during the melting process of RBDPKO, before being completely melted at 33.2°C. This work has demonstrated the detailed dynamics of polymorphic transformations of PKO and PS, two commercially important hardstocks used widely by industry and will contribute to a greater understanding of their crystallization and melting dynamics.

Encapsulation of Beta-carotene in Lipid Microparticles Stabilized with Hydrolyzed Soy Protein Isolate: Production Parameters, Alpha-tocopherol Coencapsulation and Stability Under Stress Conditions.

The objectives of this research were to study the encapsulation of beta-carotene (BC) in solid lipid microparticles (SLM) of palm stearin (PS) and stabilized with hydrolyzed soy protein isolate (HSPI), and also to investigate the effect of alpha-tocopherol (TOC) addition to the systems. Through the characterizations of SLM produced with different formulations, it was verified that systems with 5% (w/v) PS, 1.0% (w/v) HSPI, and 0.3% (w/v) xanthan gum (XG) presented the highest stability, with average diameters of approximately 1.2 µm. This formulation was applied for the production of BC-loaded SLM, with different concentrations of TOC. In SLM containing TOC, nearly 75% of encapsulated BC was preserved after 45 d of storage. The kinetic profiles for degradation of encapsulated BC were fitted to a pseudo-1st-order model, and the results showed that the main difference among the systems with different BC:TOC ratios was the residual concentration of BC. The stability of the BC-loaded SLMs was also studied after stress conditions, and the results showed that the SLMs were able to support thermal treatments over 60 °C but presented low stability after different ionic strength stresses.

Trans-free margarine fat produced using enzymatic interesterification of rice bran oil and hard palm stearin.

Trans-free interesterified fats were prepared from blends of hard palm stearin (hPS) and rice bran oil (RBO) at 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, and 80:20 weight % using immobilized Mucor miehei lipase at 60°C for 6 h with a mixing speed of 300 rpm. Physical properties and crystallization and melting behaviors of interesterified blends were investigated and compared with commercial margarine fats. Lipase-catalyzed interesterification modified triacylglycerol compositions and physical and thermal properties of hPS:RBO blends. Slip melting point and solid fat contents (SFC) of all blends decreased after interesterification. Small, mostly ß' form, needle-shaped crystals, desirable for margarines were observed in interesterified fats. Interesterified blend 40:60 exhibited an SFC profile and crystallization and melting characteristics most similar to commercial margarine fats and also had small needle-like ß' crystals. Interesterified blend 40:60 was suitable for use as a transfree margarine fat.