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1.
The objective of this study was to identify the physical properties of an interesterified soybean oil (EIESOY), containing 45% saturated fatty acids (SFA), that correlates with high oil binding capacity (OBC) and low oil loss (OL). In this study, three EIESOY samples were analyzed; a 100% sample, a 50% sample diluted with 50% soybean oil, and a 20% sample diluted with 80% soybean oil. All samples were crystallized using fast (7.78°C/min) and slow (0.1°C/min) cooling rates as well as with and without high-intensity ultrasound (HIU, 20 kHz). The 100%, 50%, and 20% samples were crystallized at 38.5, 27.0, and 22.0°C, respectively. HIU was applied at the onset of crystallization and all samples were allowed to crystallize isothermally for 90 min. After 90 min, physical properties such as crystal microstructure, hardness, solid fat content (SFC), elasticity, and melting behavior were evaluated. Physical properties were also measured after storage for 48 h at 22 and 5°C. Results show that OBC was positively correlated with hardness, G′, and SFC after 48 h (r = 0.738, p = 0.006; r = 0.639, p = 0.025; r = 0.695, p = 0.012; respectively), OL was negatively correlated with hardness after 48 h (r = −0.696, p < 0.001), G′ after 90 min and 48 h (r = −0.704, p < 0.001; r = −0.590, p = 0.002), and SFC after 90 min and 48 h (r = −0.722, p < 0.001; r = −0.788, p < 0.001). Neither OBC nor OL were correlated with crystal diameter or the number of crystals.  相似文献   

2.
The objective of this study was to use high-intensity ultrasound (HIU) to change the crystalline structure of an interesterified soybean oil (IESBO) with 33% of saturated fats and to evaluate how these changes affect oil migration. The IESBO was crystallized at different temperatures (26, 28, 30, and 32 °C) with and without HIU. Results show that oil migration was significantly affected by HIU (P < 0.05). HIU promoted crystallization and induced the formation of harder crystalline networks that were more resistant to oil migration with lower melting peak temperatures and sharper melting profiles. Samples processed with HIU had fewer crystalline clusters as observed by microscopy. Changes observed on the physical properties of the IESBO due to sonication that consequently improved oil migration were attributed to the ability of HIU to induce secondary nucleation and crystallize low-melting point triacyclglycerols (SUU) that would not crystallize without the HIU and to the stronger and stable crystalline network formed capable of entrapping liquid TAG (UUU).  相似文献   

3.
The crystallization behavior of mango kernel fat (MKF) at 25 °C with and without the application of high-intensity ultrasound (HIU) (20 kHz, 125 W) was studied as a function of ultrasound amplitude level (30%, 50%, and 70% of the maximum amplitude of 180 μm). The irradiation period was fixed at 5 s. It was found that HIU induced MKF crystallization. The crystallization induction time decreased with a decrease in crystal size and an increase in the number of crystals as the HIU amplitude increased. The β' → β transformation was also accelerated with HIU application. This work has shown that there is great potential for the use of HIU in the food industry to achieve a shorter and more controllable crystallization process. In particular, HIU could be used as an efficient tool for controlling the polymorphic transition of fats.  相似文献   

4.
In this paper, gelatin and xanthan are applied to produce a foam‐templated oleogel. For this reason, the oleogel is prepared at different concentrations of biopolymers and the properties of solution, cryogel, and related oleogel are determined. The results show that xanthan addition increases viscosity and foam stability of solution. Also, an increment in biopolymer concentration increases cryogel network density (ND) and firmness but has no significant effect on moisture sorption. The oil binding capacity of all oleogels is >92%. In terms of high foam stability (96.87 ± 4.42), low ND (0.016 ± 0.00), and consequently suitable oil sorption (46.10 ± 4.40), the oleogel containing 3% gelatin and 0.2% xanthan is selected as the best sample. Complementary tests exhibit that the oleogel, with thixotropic behavior and 60% structural recovery, can bind the oil at temperature <100 °C. The oleogel network can protect the edible oil from oxidative reaction during 2 month storage. Nonetheless, more studies are needed to attest the application of this oleogel type in food products. Practical Application: Biopolymers of gelatin and xanthan are GRAS and available so that they are applied in many food products. This research shows that the cryogel of these biopolymers, as a hydrophilic oleogelator, can be utilized to structure oil and produce oleogel in an indirect method. This procedure that forms strong gel and keeps oil even at high temperatures can be of interest to scientists who are searching for solid fat substitutes in food products such as cakes, biscuits, and muffins.  相似文献   

5.
Obesity and cardiovascular diseases are among the most worrying health problems worldwide. Dietary habits can be catalysts for the rise of these health issues in western countries. In this work, a meat product (pork patties) commonly elaborated with a high fraction of saturated fat is reformulated with an oleogel based on linseed oil (rich in polyunsaturated fatty acids). The oleogel is used for the partial replacement of the solid fat fraction present in pork patties (H‐25 for 25% and H‐75 for 75% of replacement). Incorporation of oleogels results in the modification of the fatty acid profile and in the significant decrease of the omega‐6/omega‐3 ratio. Results show that for both degrees of fat substitution, there are no differences between the patties produced with oleogel incorporation and the control, regarding textural parameters such as hardness, cohesiveness, and chewiness. Overall, samples with less amount of oleogel (H‐25) are well classified in the acceptance and preference tests, despite the clear preference among the sensorial panel toward the control samples. These results show the feasibility of introducing oleogels as a fat replacer in the manufacturing process of pork patties, though there is still work to be done regarding some of their sensorial attributes. Practical Applications: The purpose of this work is focused on the study of the properties of meat patties after the replacement of saturated fat with a multicomponent oleogel, foreseeing the hamburger production. The results show that the oleogel incorporation in meat patties is possible at the industrial level without additional unitary steps during meat patty production. Based on this work it is possible to produce meat patties with adjusted fatty acids profiles.  相似文献   

6.
The objective of this work was to evaluate the effect of high intensity ultrasound (HIU) on the physical properties of a commercial shortening crystallized at a constant temperature and during temperature cycling at two different cooling rates (0.5 and 1 °C/min). Different ultrasound power levels and different durations were evaluated during crystallization at a constant temperature and the best conditions were used to evaluate the effect of HIU during temperature cycling. The physical properties tested were crystal microstructure, viscoelasticity, and melting profile. Results show that HIU is more efficient at changing crystal microstructure when used at 20 °C using a 1/2″ tip. No difference was found on the microstructure of the crystals formed when different durations of ultrasound exposure were tested. A significant increase (p < 0.05) was observed in the storage modulus (G′) of the lipid exposed to temperature fluctuations with the use of HIU. The G′ values increased from 662.6 ± 176.8 Pa (no HIU applied) to 3,365.5 ± 426.4 Pa (with HIU applied, 0.5 °C/min) and from 354.4 ± 49.7 Pa (no HIU applied) to 1,249.0 ± 19.8 Pa (with HIU applied, 1 °C/min).  相似文献   

7.
Oleogelation is emerging as one of the most exigent oil structuring technique. The main objective of this study was to formulate and characterize rice bran/sunflower wax-based oleogels using eight refined food grade oils such as sunflower oil, mustard oil, soybean oil, sesame oil, groundnut oil, rice bran oil, palm oil, and coconut oil. Stability and properties of these oleogels with respect to oil unsaturation and wax composition were explored. Sunflower wax exhibited excellent gelation ability even at 1%–1.5% (w/v) concentration compared to rice bran wax (8%–10% w/v). As the oleogelator concentration increased, peak melting temperature also increased with increase in strength of oleogels as per rheological studies. X-ray diffraction and morphological studies revealed that oleogel microstructure has major influence of wax composition only. Sunflower wax oleogels unveiled rapid crystal formation with maximum oil binding capacity of 99.46% in highly unsaturated sunflower oil with maximum polyunsaturated fatty acid content. Further, the applicability of this wax based oleogels as solid fat substitute in marketed butter products was also scrutinized. The lowest value of solid fat content (SFC) in oleogel was 0.20% at 25°C, resembling closely with the marketed butter products. With increase in oil unsaturation, oleogels displayed remarkable reduction in SFC. Depending upon prerequisite, oleogel properties can be modulated by tuning wax type and oil unsaturation. In conclusion, this wax-based oleogel can be used as solid fat substitute in food products with extensive applications in other fields too.  相似文献   

8.
Physical properties of fats are affected by the reduction of saturated fatty acids. One method for retaining desired properties is the use of high-intensity ultrasound (HIU). The aim of this study was to investigate the influence of HIU power levels, pulse time, and position on the physical properties of a low-saturated palm-based fat crystallized in a scraped surface heat exchanger (SSHE). The sample was crystallized in a SSHE at 26 °C, using a 11 L hour−1 flow rate, and agitation of 344 rpm in the barrels and 208 rpm in the pin worker. HIU was applied using a 12.7 mm tip coupled to a water jacketed (26 °C) flow cell that was placed at the end of the SSHE process. Sonication conditions were 20%, 50%, or 80% amplitude using pulses (5 and 10 s) or continuous sonication. After choosing the best HIU condition, the position of the flow cell was changed to different positions within the SSHE: before the first barrel (HIU-0), between the two barrels (HIU-1), between the second barrel and the pin worker (HIU-2), and after the pin worker (HIU-3). The best sonication condition from the first set of experiments was when HIU was applied using 50% amplitude and 10 s pulses. This condition resulted in higher oil binding capacity (OBC) and storage modulus (G') compared to the non-sonicated sample (OBC: 77% against 69.5%; G':154 kPa against 108 kPa). The best HIU position was HIU-3 since no further agitation was applied. The lack of agitation after sonication induced secondary nucleation and generated a strong crystalline network.  相似文献   

9.
Membrane distillation crystallization (MDC) was introduced and investigated for the simultaneous treatment of saline organic wastewater generated from oil extraction, in this article. The developed process model of MDC for the investigated ternary system was validated by the experiments with good agreement. Under the tested feed ethylene glycol (EG) composition and operation conditions, the highly concentrated EG (residual side, recovery ratio > 98.7%), pure water (permeate side, purity > 99%), pure crystals with narrow crystal‐size distribution, and desired morphology were simultaneously manufactured. By this simultaneous recovery of EG and H2O in the feed flow, the overall separation efficiency was enhanced. The impact factors of the crystal properties during MDC were also revealed by comprehensive analysis. Moreover, the diverse metastable zone width and crystal morphology obtained in different feed EG composition indicated the change of the nucleation barrier and the kinetic crystallization control mechanism. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2187–2197, 2017  相似文献   

10.
Several studies have reported the use of high-intensity ultrasound (HIU) to induce the crystallization of lipids. The effect that HIU has on lipid crystallization is usually attributed to the generation of cavities but acoustic cavitation has never been fully explored in lipids. The dynamics of a particular cavitation cluster next to a piston like emitter (PLE) in an oil was investigated in this study. The lipid systems, which are important in food processing, are studied with high-speed camera imaging, laser scattering, and acoustic pressure measurements. A sequence of stable clusters was noted. In addition, a bifurcated streamer was detected, which exists within a sequence of clusters. This is shown to originate from two clusters on the PLE tip oscillating with a 180° phase shift in time with respect to one another. Finally, the collapse phase of the cluster is shown to involve a rapid (~10 μs) two-stage process. These results show that the dynamics of cluster formation and collapse is driven by HIU power levels and might have implications in lipid sonocrystallization.  相似文献   

11.
Virgin olive oil and beeswax were used to prepare four oleogel emulsions (EM1–EM4) through simultaneous oleogelation emulsification, and these oleogels were compared with breakfast margarine (BM). The melting temperatures of the oleogel emulsions ranged from 52.29 to 57.52 °C, while it was 40.36 °C for the BM sample. Similarly, the solid fat content (SFC) of the oleogel emulsions was between 3.57 and 3.68 % at 20 °C, and that of BM was 7.70 %. Except the EM3 sample, all oleogel emulsions exhibited mechanical stability. The firmness and stickiness values of the oleogel emulsion samples were lower than those of the BM sample, but they remained almost constant through 90 days of storage. Furthermore, the fine water droplets and needle‐like beeswax crystals within the continuous oil phase were stable during the storage. The X‐ray diffraction patterns of the samples revealed that the oleogel emulsions contain crystals similar to β′ polymorphs, characterized by a homogenous, smooth and fine texture. The presence of inter and intramolecular hydrogen bonds was proved by Fourier Transform Infrared (FT‐IR) measurements. The developed oleogel emulsions were found to be stable in terms of texture, color and oxidation during 90 days of storage. In conclusion, these oleogel emulsion products can be used as margarine/spread stocks.  相似文献   

12.
Oleogels and emulgels were developed with winterized algal oil from Schizochytrium spp. rich in ω-3 fatty acids (FAs) to overcome physical limitations of using a highly unsaturated lipid source in food applications. Both gel types were developed using monolaurin or a combination of mono- and diacylglycerols (MAG/DAG) as the gelator at concentrations of 8%, 10%, or 12% (w/w) in oil or emulsion. A 30-day oxidation study was conducted using peroxide value, p-Anisidine value, and change in FA composition to measure the level of oxidation. Oleogel and emulgel samples exhibited a higher oxidative stability than bulk algal oil and oil-in-water emulsion as control groups, respectively. The 12% monolaurin oleogel outperformed others in oxidative stability, preventing oxidation of approximately 11.66% and 7.86% of EPA and DHA, respectively, compared to algal oil. Physical characteristics including thermal behavior, solid fat content (SFC), rheology, morphology, and polymorphism were studied. Results indicated that MAG/DAG oleogels and monolaurin emulgels were the most physically stable. The SFC of 12% MAG/DAG oleogel at 30°C was 10.27% whereas 12% monolaurin oleogel was only 4.51%. Both gel types developed with monolaurin and MAG/DAG could be used for different applications as they exhibited desirable qualities such as oxidative stability and improved physical characteristics.  相似文献   

13.
The objective of this research was to evaluate the effect of high‐intensity ultrasound (HIU) and crystallization temperature (Tc) on the crystallization behavior, melting profile, and elasticity of a soft stearin fraction of high‐stearic high‐oleic sunflower oil. Results showed that HIU can be used to induce and increase the rate of crystallization of the soft stearin with significantly higher SFC values obtained in the sonicated samples, especially at higher Tc. SFC values were fitted using the Avrami model, and higher kn and lower n values were obtained when samples were crystallized with sonication, suggesting that sonicated samples crystallized faster and through an instantaneous nucleation mechanism. In addition, the crystal morphology, melting behavior, and viscoelasticity were significantly affected by sonication.  相似文献   

14.
The dermal route is important in occupational exposure to polycyclic aromatic compounds (PACs), but other organs may be affected. We reported that kerosene-cleaning following treatment with used engine oil increased DNA adducts in the lungs of mice viz. animals treated with used oil alone. To determine the mechanism we topically applied 3 H-BAP(100 nmol in 25 μL acetone) and washed half the mice with 25 μL kerosene 1 h after carcinogen application. Groups of four mice were sacrificed from 1 to 72 h after treatment. Lung, liver, and skin were harvested. The fraction of the radiolabel remaining in the skin of animals treated with benzo[a]pyrene (BAP) and washed with kerosene was significantly less than those not washed, beginning at 24 h (p < .05). Fractional distribution to the lungs and livers of these animals became significantly elevated. Kerosene increased transdermal water loss. Kerosene treatment compromises dermal barrier function, enhances carcinogen absorption, and alters organ distribution.  相似文献   

15.
The purpose of this research was to determine the effect of high-intensity ultrasound (HIU) on physical properties, degree of oxidation, and oxidative stability of structured lipids (SLs). Caprylic acid (C) and stearic acid (S) were incorporated into menhaden oil using Lipozyme® 435 lipase to obtain five samples: (1) LC 20 (menhaden oil with 20% of C), (2) LC 30 (menhaden oil with 30% C), (3) LS 20 (menhaden oil with 20% S), (4) LS 30 (menhaden oil with 30% S), and (5) Blend C (menhaden oil with 16.24% C and 13.04% S). Samples were crystallized for 90 min at the following temperatures: (1) LC 20 at 15.5°C, (2) LC 30 at 17.5°C, (3) LS 20 at 24°C, (4) LS 30 at 30°C, and (5) Blend C at 18.0°C, and HIU was applied at the onset of crystallization. Physical properties, degree of oxidation, and oxidative stability were evaluated in sonicated and nonsonicated samples. All SLs had statistically higher G′ after sonication. Sonicated LS 30, LC 30, and Blend C had a higher melting enthalpy than the nonsonicated ones, while enthalpy values in sonicated LS 20 and LC 20 samples were not statistically different than the nonsonicated ones. No significant difference between sonicated and nonsonicated samples was observed in peroxide values (1.2 ± 0.1 meq/kg, p > 0.05) and in the oxidative stability index (6.3 ± 0.2 h, p > 0.05). These results showed that HIU was effective at changing physical properties without affecting the oxidation of the samples.  相似文献   

16.
β‐Sitosterol (Sit) and stearic acid (SA) were combined at varying ratios (w/w) and added to sunflower oil (SFO) at the concentration of 20 g/100 g oil for preparing edible fat‐like oleogel. The oleogel was characterized using an optical microscope, Fourier transform infrared spectroscopy (FTIR), X‐ray diffractometer (XRD), differential scanning calorimeter, and texture analyzer. The oil‐binding capacity, melting temperature, and firmness of the oleogel increased with the increase in the amount of SA in the gelator combination (Sit:SA, w/w). The microscopic analysis showed that the gel network formed based on the crystallization and self‐organization of gelator molecules, and both gelators showed an independent crystalline behavior in the oleogel. In addition, the FTIR spectra showed that the gel network formed via physical entanglements and was stabilized by non‐covalent interactions such as hydrogen bonding. Furthermore, XRD diffraction patterns indicated high lateral packing of molecular layers in oleogel prepared with the Sit and SA combination compared with oleogel prepared with a single gelator. On the other hand, for studying the effect of varying concentrations of gelator combinations, the Sit3:SA2 (w/w) combination was added to SFO at concentrations of 10, 15, 20, 25, and 30 g/100 g oil. Specific characteristics such as the oil‐binding capacity and firmness of the oleogel improved as the concentration of the gelator combination (Sit3:SA2) increased from 10 up to 30 g/100 g oil. Therefore, it can be concluded that the saturated fat alternative oleogel can be prepared from SFO with a specific Sit and SA combination ratio and concentration.  相似文献   

17.
Cookie fillings are typically composed of sugar (60%–80%) and fat (20%–40%). The fat in these fillings is known as shortening, which currently has high levels of saturated fatty acids (SFA) and, in some cases, trans fatty acids (TFA). This makes the nutritional profile of this product a reason for concern, especially considering that the target audience for cookies is children. This study thus aimed to replace the commercial shortening in these fillings with oleogels made of soybean oil (SB) and high oleic sunflower oil (SF) structured with candelilla wax (CLX), monoglycerides (MG), and hard fat (HF), in different concentrations ranging from 5%–10% of the total structuring content. The complete replacement of shortening with oleogel reduced the amount of TFA by 100% and the amount of SFA by 50%–80%. The quantities of MG and HF greatly influenced the structuring of the product because the higher the concentrations (≥3%), the better the formation of the structured network, with good aeration, greater hardness, and less oil loss, compared with the standard with shortening. The samples that achieved physical properties similar to those of the control sample were samples 3:3:3 and 1:4:5 (CLX:MG:HF). These showed similar oil loss at T0 (~4.5%), and microstructure before and after temperature oscillations and closer consistency (~400 gF/cm2) and adhesiveness (50 gF. s) to the RP (800 gF/cm2 and 75 gF. s). Although MG and HF are not good structuring elements alone as the CLX, they formed a network that is connected by hydrogen bonds with the sugar molecules that were resistant to stirring and thermal changes, which makes this system a potential replacement for shortenings in cookie fillings application.  相似文献   

18.
Crude wax extracted from rice bran oil (RBO) is used to improve the oleogel properties and oxidative stability of RBO. The effect of crude rice bran wax (CrBW) on the formation characteristics and oxidative stability of oleogels is discussed. The results show that oleogels can be formed with 7.0 wt% CrBW at 20 °C. As the concentration of CrBW increases from 7.0 to 11.0 wt%, the hardness and solid fat content (SFC) of the oleogels increase significantly, and the oleogels are primarily β' crystals. Moreover, oleogel crystals formed with 5 and 7 wt% CrBW are flocculent; when the amount included is 9%, the oleogel crystals are transformed into long dendrites, and the density rises. After 90 days of storage at 20 °C, the peroxide value of oleogels formed with 9.0 wt% CrBW slowly rises from 3.21 to 6.52 mmol kg−1. Practical Applications: Oleogels prepared here by CrBW and RBO are an innovative structural lipid without trans fats. Useful information on the rich fats and nutrients in CrBW is provided, which reduces the production cost and improves the industrial production capacity.  相似文献   

19.
20.
Amorphous nylon 6 film iodinated before forming with an aqueous solution of 1.0N iodine–potassium iodide (I2/KI) was deiodinated by dipping in water/ethylene glycol (EG) solutions of sodium thiosulfate with various EG contents and temperatures, washed with water, and dried at ambient condition. Structural variation through deiodination and the effects of the deiodination conditions were investigated by X‐ray diffractometry and differential scanning calorimetry. The degree of swelling of the films immediately after deiodination and the time required to complete the deiodination were generally increased and decreased, respectively, with increasing temperature and EG content. The amorphous iodinated film was crystallized through deiodination. The α‐crystal formation became easier with increasing temperature and EG content in the solution. The crystallinity of the films was higher after drying than before drying, suggesting that the drying induced further crystallization without any significant conversion of crystal type. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

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