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1.
The microstructure, melting and crystallization behavior, rheological properties and oil binding capacity of crystalline networks of plant-derived waxes in edible oil were studied and then compared amongst different wax types. The critical concentrations for oleogelation of canola oil by rice bran wax (RBX), sunflower wax, candelilla wax, and carnauba wax were 1, 1, 2, and 4 %, respectively, suggesting RBX and sunflower wax are more efficient structurants. A phenomenological two-phase exponential decay model was implemented to quantify the oil-binding capacity of these oleogels. Parameters obtained from this empirical model were then evaluated against microscale structural attributes such as crystal size, mass distribution and porosity to determine the structural dependence of oil-binding capacity. Gels containing candelilla wax exhibited the greatest oil-binding capacity, as they retained nearly 90 % of their oil. This is due to the small crystal size as well as the spatial distribution of these crystals. Using a microscopic to macroscopic approach, this study examines how the structural characteristics unique to each wax and resulting oleogel system affect functionality and macroscopic behavior.  相似文献   

2.
Waxes Having High Dispersibility and Special Consideration of Their Suitability in the Manufacture of Colouring Masses for Carbon Paper Increasing amounts of waxes having fundamentally different chemical composition are being used as dispersion aids. In the manufacture of colouring masses for carbon papers, the materials used as vehicle of the colour and as dispersing agent for carbon black are hydrocarbons, wax acids and their natural esters. Whereas low-priced paraffins are mainly used for cheap carbon papers meant for a single use, carnauba wax is used for better quality carbon papers which can be used several times. The latter wax is especially suited because of its carbon black-dispersing and oil-binding properties. Since crude montana wax does not have these properties to such an extent as the carnauba wax, it was attempted to improve the carbon black-dispersing and oil-binding of montana wax by chemical synthesis. This was achieved by reacting crude montana wax with maleic anhydride and subsequent esterification of the reaction products with glycols. The results were successfully applied to the solution of problems involving dispersion of pigments and plastic additives.  相似文献   

3.
Four natural waxes were evaluated as stabilizers in peanut butter. The potential advantage of using natural waxes would be the replacement of current stabilizers such as hydrogenated or tropical oils, thereby reducing saturated fats and satisfying clean label requirements. Beeswax (BW), candelilla wax (CLW), rice bran wax (RBW), sunflower wax (SFW), and a commercial peanut butter stabilizer, hydrogenated cottonseed oil (HCO), were added to three natural peanut butter brands at levels ranging from 0.5% to 2.0% (w/w) and tested for accelerated oil release, long-term stability, firmness, and rheology. At levels ≥0.5%, all waxes improved oil-binding capacity (OBC). SFW and HCO had the highest OBC, followed by RBW, CLW, and BW. All waxes reduced the amount of oil separation after 6 months at 22 ± 2 °C. HCO followed by SFW reduced oil separation the most, but there were no significant differences between stabilizers at 1–2%. Firmness and yield stress increased with increasing stabilizer level, with SFW increasing firmness the most, followed by HCO, RBW, and CLW, while BW had the lowest effect. The results indicate that the waxes may be feasible replacements for hydrogenated oils as peanut butter stabilizers, but levels would need to be optimized depending on the product characteristics and wax type.  相似文献   

4.
External laminar oscillatory shear applied during crystallization in combination with different temperature fields was used to modify the microstructure and physical properties of edible oil organogels. Crystallization at a high cooling rate (30 °C/min) resulted in a spherulitic microstructure with a higher oil-binding capacity, lower storage modulus and lower yield stress compared with a material (with a fibrillar microstructure) crystallized at a slow cooling rate (1 °C/min). The application of an oscillatory shear resulted in the formation of novel microstructures depending on the cooling regime used. The application of an oscillatory shear (strain > 500 % and frequency = 1 Hz) resulted in the thickening of fibers observed in the slow-cooled material and an increased incidence of spherulite nucleation in the rapidly cooled material. Increasing the frequency of the oscillatory shear applied did not change the microstructure for the slow-cooled gel but further increased the incidence of nucleation for the rapidly cooled gel. The application of controlled-strain oscillatory shear to the crystallizing gel at either cooling rates resulted in an oily and very soft, paste-like material. This material had a lower storage modulus and poorer oil-binding capacity compared with the same gel crystallized statically. Reduction of the oscillatory strain from a maximum of 1500 to 500 % moderately mitigated the loss of mechanical properties and oil-binding capacity although these properties were in no way comparable to those obtained from static crystallization. The study shows that the application of oscillatory shear and different cooling regimes can be used to tailor a crystalline organogel. However, the application of continuous shear must be done with care as application of excessive shear can result in a complete breakdown in gel structure and large amounts of oil loss.  相似文献   

5.
A process for the preparation of yeast-derived food additives was developed. The four products obtained, yeast protein concentrate (YPC), cell-wall protein (CWP), semi-pure glucomannan (SPG) and yeast extract, compared well with similar products, present in the current market, with respect to functional properties. YPC and CWP exhibited improved water-holding and oil-binding properties over those of soy-protein isolate (SPI). The emulsifying capacity was very close to that observed in commercial samples. A one-step alkaline extraction enhanced the functional properties of primary yeast glycan to match traditional food hydrocolloid sources. SPG showed oil-binding properties significantly greater than commercial glucomannan.  相似文献   

6.
The Analysis of Hydrocarbon Mixtures with the Help of Selective Extraction Methods × — Analysis of Crude Waxes from a Paraffin Based Crude Oil The analysis of three crude waxes from different fractions of paraffin based crude oil, with the help of solid-liquid extraction and finally by urea-adduct formation, is reported. On the basis of selected physical data and suitable diagrams, the structural composition of the hydrocarbon components of these three crude waxes is discussed.  相似文献   

7.
Natural Waxes XI: Synthesis and Gas Chromatography of Higher Cyclohexyl Paraffins Eight cyclohexyl nonadecanes, 1-cyclopentyl eicosane, and three methyl pentacosanes were prepared by Grignard syntheses to serve as model substances in the investigation of minor components of natural waxes. The retention volumes of the pure substances on three different stationary phases (Apiezon L, SE-30, QF-1) were determined by gas chromatography and their mass and infrared spectra were taken. The effect of the position of substituent on the elution behaviour was studied on a series of cyclohexyl and methyl paraffins. The anomalous behaviour of 2-methyl pentacosan, as reported earlier, was confirmed.  相似文献   

8.
Impact of Chemical and Physical Data on the Practical Properties of Vaseline 6: Correlation Analysis and Results Relationships (linear, log-log, and log-linear) between the data on chemical analysis of structural groups, physical data, and practical properties of 28 different varieties of vaseline have been determined by a digital computer using ALGOL-program. The results are given in two schemes. Two types of vaseline have been found: a) vaselines having low tack, poor oil-binding ability, and a crystalline structure owing to the n-paraffins; b) high tack vaselines that are thixotropic also in sheared state, have good oil binding properties, and form micelles with high molecular weight iso-paraffins. The common methods for physical determination, as described in most pharmacopiae, should be replaced by rheological measurements, dilatometry and determination of oil number. Both sheared and unsheared vaselines should be examined.  相似文献   

9.
The Model Wax for the Precision Metal Castings After a short review of the history and the technique of precision metal casting on lost model waxes, the requisite properties of such waxes are given in details. The sum of all these properties can be achieved only by mixing different types of waxes with one another or by combination with other substances. At the same time, the molecular structure of the waxes also plays an important role. The relation between this and the shrinkage is shown by means of experimental investigations on a number of examples.  相似文献   

10.
Fat Accompanying Components of the Oil of Sea Buckthorn The water steam distillate mainly contains esters of ethanol and of isoamylalcohol with fatty acids and benzoic acid as well as benzaldehyde and benzylalcohol. The composition of the shell waxes and the unsaponifiable of flesh oil and seed oil were determined. The unsaponifiable of the flesh oil consists of long chain epoxides, alcohols, sterols and triterpenes. The main component of the unsaponifiable of the seed oil is phytol.  相似文献   

11.
Valorization of the agri-food industry by-products could contribute to curb issues related to food security and environmental problems. Flax and wheat seeds are major products of this industry, but their production is associated with tons of straws that can be valorized for their cuticular and epicuticular waxes. We aimed to determine the organogelation capacity of epicuticular waxes in comparison to cuticular waxes from both flax and wheat straws. Epicuticular waxes from flax and wheat straws have structured canola oil at 2% and 4% (w/w), respectively, whereas cuticular waxes from flax and wheat straws required critical concentrations of 4% and 5% (w/w), respectively. Characterization of the organogelation capacity (onset of crystallization temperature, temperature of phase transition, crystal morphology, solid fat, crystalline structure, and oil binding capacity) was also carried out. The high onset of crystallization temperature (38.1 ± 1.2°C), the phase transition at high temperature (38 ± 1.5°C), and capacity to structure canola oil at low concentration showed that epicuticular wax from flax straw is a promisor fat substitute, presenting organogelation properties comparable to the best results obtained in the literature for other vegetal waxes.  相似文献   

12.
Diester Waxes and Unusual Fatty Acids in Lipids of Sebaceous Gland Systematic investigations of lipids of sebaceous gland of birds have shown close relationship between the structure of these lipids and the individual species in the natural system of birds. In almost all the species studied so far the lipids of sebaceous gland consist of wax esters which are made up of unusual fatty acids and alcohols. Thus in the group of passeriformes (sparrows) 3-methyl substituted fatty acids, in the group of strigiformes (owls) 2-propyl and 2-butyl substituted fatty acids, and in the group of columbiformes (pigeons) 3-hydroxy fatty acids are found as constituents of the wax esters. Diester waxes are found in galliformes (hens), columbiformes, limicolae (snipes) and in some members of passeriformes. Unusual constituents of these waxes are alkanediols, 3-hydroxy fatty acids, and alkylhydroxymalonic acids. The structures were elucidated by a combination of GLC and mass spectrometry. Some of the mass spectra are discussed.  相似文献   

13.
Changes in the contents of waxes and fatty alcohols during deodorization/physical refining of bleached olive oil were studied. Experiments were carried out with 1.85% acidity oil, which was physically refined in a discontinuous deodorizer of 250-kg maximum capacity using nitrogen as stripping gas instead of steam. The variables studied were load and temperature of oil in the deodorizer as well as N2 flow. Analyses of waxes and alcohols were carried out at different operation times. The maximum content of wax was always observed when the oil reached the deodorization temperature. The variation in the wax content depended on temperature and N2 flow. Wax decomposition started and continued during the operating time, and a progressive decrease, which was pronounced between 3 and 4 h, was observed. Small changes in waxes were observed between 4 and 5 h. Total content of fatty alcohols diminished throughout the operating time, and changes did not depend on the variables studied.  相似文献   

14.
  1. The potentiometric titration method is superior to color-indicator methods in the determination of acid and saponification values of earth waxes.
  2. The saponification reaction in determining saponification values of earth waxes is a balanced one; therefore the equilibrium depends on conditions under which it is run.
  3. Hydroxyl and carbonyl value methods have been modified to make them suitable for earth (mineral) waxes.
  4. The values obtained on high-molecular weight peat waxes are not absolute, but rather they serve to characterize and identify these products.
  5. The methods explained in this report may perhaps be found suitable for other natural products, such as montan wax.
  相似文献   

15.
Winterization of Sunflower Oil Properties of sunflower oil that influence the process of winterization, were investigated. Moreover, the conditions of crystallization of waxes and mixed chain glycerides were studied. Filtration performance and the significance of the use of filter aids are discussed in examples of plants that are described. A new type of filter appears promising for the solution of problems associated with winterization.  相似文献   

16.
A Contribution to Determine the Hoeppler-Hardness It was investigated in which limits the Konstistometer (according to Hoeppler) with measuring unit IV (steel cone) manufactured by Haake GmbH, Karlsruhe, is suitable for measuring the hardness of waxes. A load of 15 N (1500 p) gave a depth of penetration, which was sufficient to keep the fault range below ± 5%. The resulting penetration craters were checked for cracks and wall formation by electron scanning microscopy. A strong dependence of Hoeppler hardness from the crystal structure of the wax was observed in some cases.  相似文献   

17.
Identification of Genuine Natural Waxes by Thin-Layer Chromatography Genuine waxes can be identified distinctly in a reproducible manner by examining certain extracts of these waxes by thin-layer chromatography. Using benzene as mobile phase, the extracts are resolved on Silicagel HF plates into individual components that were not investigated further. Under UV light these components are visible as coloured fluorescent spots, whose number, RF-values and fluorescent colours are characteristic for the genuine natural waxes.  相似文献   

18.
In order to get more knowledge about the fundamentals of solvent-free slack wax de-oiling by melt crystallization, investigations on multicomponent paraffin waxes have been performed, which included X-ray powder diffraction and optical microscopy. The tested neutral oil and medium slack waxes consisted mainly of n- and iso-paraffins with different chain lengths. The results suggest that only n-paraffins formed orthorhombic crystals at room temperature with c-axes corresponding to the average chain length of the paraffin waxes. The crystals were surrounded by less crystalline, rather amorphous, solid phase containing mainly iso-paraffins. The typical solid–solid transition of crystal lattice in neutral oil slack waxes from orthorhombic to hexagonal system at temperatures below melting point increases the mobility of the low melting components. This is the key for the applicability of the melt crystallization process. Investigations on sweating suggest a strong influence of the n-paraffins content on mechanical stability of crystal structures and on the separation efficiency of sweating.  相似文献   

19.
Emulsification of Oxidized Polyethylene Waxes with Ionic-Nonionic Emulsifier Systems II Studies using methods described earlier were extended to emulsification of oxidized polyethylene waxes having varying acid values and molecular weights with nonionic-ionic emulsifier systems. Besides nonylphenolethoxylates C9/11- and C13/15-fatty alcohol ethoxylates were also used in the presence of various amines as emulsifiers. The optimum degree of ethoxylation for each emulsifier was determined within each class of ethoxylate as a function of the degree of oxidation of polyethylene waxes. The efficiency of various classes of ethoxylation products and the influence of various amines were compared under different conditions.  相似文献   

20.
Waxes are important as building material and for the chemical communication of the honeybee Apis mellifera carnica. In this study chemometric tools were established for classifying the different waxes inside the hive. By using gas chromatography in combination with mass spectrometry, components of different types of waxes were analyzed. By considering different substance classes of waxes, discriminant function analyses revealed distinct subtypes of comb waxes and of cuticular waxes. It is shown that the aging of comb wax is in part a spontaneous physicochemical process due to differential volatilities of compound classes with different chain length ranges. On the other hand it is directly influenced by the bees by adding lipolytic enzymes to the comb wax. The data suggest that the varying cuticular wax and comb wax compositions could serve as cues for bees to recognize castes, sexes, or comb age.  相似文献   

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