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1.
Coconut oil is rich in medium chain triglycerides but lacks polyunsaturated fatty acids (PUFA) and bio‐active phytoceuticals. In the present work nutra‐coconut oil was prepared by blending coconut oil and flaxseed oil (70:30) and adding 3000 ppm of flaxseed cake concentrate using ethanol, methanol and 20 % aqueous ethanol. The concentrate prepared from flaxseed was from ethanol as it gave maximum yield. The different bio‐active molecules in flaxseed concentrate observed are polyphenols (39.04 %), tocopherols (4.37 %), ferulic acid (0.17 mg g?1), p‐coumaric acid (2.24 mg g?1), chlorogenic acid (16.11 mg g?1), gallic acid (8.58 mg g?1), sinapic acid (0.64 mg g?1) and secoisolariresinol (30.13 mg g?1). The nutra‐coconut oil was found to have polyphenols (2.86 %), tocopherols (442.96 ppm) and antiradical activity (94 %). The PUFA content was found to increase in nutra‐coconut oil significantly (p < 0.05) (2–22 %). The FT‐IR spectra of nutra‐coconut oil revealed that the peak at 3009 and 1651 cm?1 was associated with the presence of unsaturated fatty acids. There was no significant (p > 0.05) difference observed in sensory attributes of snack food fried using coconut oil and nutra‐coconut oil indicating that the later could be used as a frying medium and useful for food processing industries.  相似文献   

2.
The seeds of Commiphora wightii (Arnott) Bhandari contain 9.8 ± 0.7% oil. The fatty acid composition and chemical properties of the extracted oil were determined. Gas liquid chromatography of the methyl esters of the fatty acids shows the presence of 46.62% saturated fatty acids and 51.40% unsaturated fatty acids. The fatty acid composition is as follows: capric acid 3.50%, myristic acid 14.51%, palmitic acid 6.68%, stearic acid 4.70%, arachidic acid 3.18%, behenic acid 14.05%, myristoleic acid 1.34%, palmitoleic acid 12.07%, oleic acid 14.15%, eicosenoic acid 0.11%, linoleic acid 22.34% and alpha linoleic acid 1.37%.  相似文献   

3.
Liquid oil containing high concentrations of diacylglycerols (DAG > 80 %, hereafter referred to as DAG-rich oil) is generally more likely to cause precipitation at chilled temperatures (clouding phenomena) than triacylglycerol-based oil. The clouding phenomena that occur during long-term storage of DAG-rich oil are unwanted in consumer products and therefore, must be prevented. In the present study, we attempted to retard precipitation by adding food emulsifiers, polyglycerol fatty acid esters (PGFE) containing different fatty acid moieties. DSC, polarized optical microscopy, and X-ray diffraction studies revealed that the addition of 0.2 % PGFE containing palmitic and oleic acid moieties very effectively retarded precipitation in the DAG-rich oil. To confirm these observations, we prepared a model DAG oil to mimic DAG-rich oil and examined the retardation behavior of high-melting DAG fractions using PGFE. The results are discussed in terms of the effects of PGFE additives on the pre-nucleation processes of high-melting fractions in DAG-rich oil.  相似文献   

4.
In this study, mixtures of purified wax and sterols were melted and subsequently cooled. Using X-ray diffraction of the mixed, solid phase, it was shown that for up to 30–40 wt% sterols no measurable re-crystallisation of sterols occurred, i.e. the sterols became dissolved at a molecular level. Probably a form of amorphous co-crystals of sterols and wax is formed if the molecular ratio does not exceed 1:1. Differential scanning calorimetry (DSC) suggests that a minor amount of pure sterols could already be present at lower sterol levels. This may be because of the higher temperature at which the microstructure is probed when using DSC—melting of the wax might lead to crystallisation of the sterols. For application in foods, the structure as probed by X-rays at ambient temperatures is more relevant. When sunflower wax and rice bran wax are used, prevention of sterol crystallisation is even more pronounced, probably because the melting temperatures of these waxes are closer to the melting temperature of sterol crystals. Replacing the beeswax with a saturated fat (heRP70), sunflower oil, or jojoba wax (a liquid wax) substantially increases the amount of crystalline sterols. The difference between the various waxes and fats was qualitatively the same for X-ray diffraction and DSC. Stanols can be incorporated in the same manner and up to similar concentrations. Another insoluble nutritional compound, ursolic acid, has a greater tendency to crystallise in wax. This is probably because the melting temperature of ursolic acid is much higher than that of wax.  相似文献   

5.
As one of the key ingredients in feed for rearing salmon the stability of the synthetic feed pigment Carophyll Pink® (CP) and the natural pigment Panaferd‐AX® (PAN) in pure cod liver oil were investigated. As reference, pure cod liver oil without added carotenoids was used (PURE). Carotenoid content, isomerization of astaxanthin in CP and distribution of carotenoids in PAN and the antioxidant ability of CP and PAN were followed by HPLC in two model experiments (Experiment 1: 17 days, temperature 18.5–28.2 °C, and Experiment 2: 15 days, temperature 29.7 °C). Moreover, peroxide value (PV), thiobarbituric value (TBARS) and fatty acid (FA) compositions were analyzed in CP, PAN and PURE. Relative to cod liver oil with added PAN, addition of CP resulted in significantly higher stability of ∑PUFA, slower formation of peroxides, reduced oxidation and increased carotenoid stability during storage. For the isomerization of astaxanthin in CP a significantly decrease in all‐E‐astaxanthin and an increase in 13Z‐astaxanthin was observed during storage in both experiments. Highest stability of different carotenoids in PAN were found for the carotenoid β‐carotene in both experiments, followed by echinenone and astaxanthin in Experiment 1 and astaxanthin, adonirubin and adonixanthin in Experiment 2. It is concluded that the synthetic pigment feed additive CP significantly improves the stability of cod liver oil as compared to the natural pigment feed additive PAN (order of stability; CP > PAN > PURE).  相似文献   

6.
Lipid composition by class, fatty acids, natural antioxidants (carotenes, tocopherols) and physicochemical characteristics of liver oil from three commercial rays, Rhinoptera bonasus (Chucha), Aetobatus narinari (Pinta) and Dasyatis americana (Bala) from the Gulf of Mexico were analyzed. Liver oil yield for R. bonasus, A. narinari and D. americana were of 43.04, 41.2 and 38.2% (wet weight), respectively. Triacylglycerols were the most abundant lipid by class in R. bonasus (68.9%), A. narinari (85.9%) and D. americana (81.6%), while sterols esters, sterols, di- and monoacylglycerides, polar lipids and wax esters were found in minor proportions. Species showed similar carotenes concentration, 8.7, 12.8 and 8.0 μg/g for R. bonasus, A. narinari and D. americana, respectively. α-tocopherol concentration was higher (p < 0.05) for A. narinari (46.7 mg/100 g) than for R. bonasus (21.0 mg/100 g) and D. americana (13.7 mg/100 g). Omega-3 polyunsaturated fatty acids in R. bonasus were high with docosahexaenoic acid (12.1%) in a higher proportion than eicosapentaenoic acid (7%).  相似文献   

7.
β-Sitosterol and γ-oryzanol have been shown to form unique structures in canola oil that have the potential to act as saturated and trans fat replacers [17]. The ternary phase, reported herein, illustrates numerous interesting physical systems. At high canola oil ratios with low β-sitosterol and γ-oryzanol concentrations, the system has a crystal structure capable of mimicking fat crystal networks. Four mesophases are identified based on Bragg’s ratios using small angle X-ray scattering. Two mesophases are lamellar crystals, one is the cubic P phase, and the fourth is an amorphous material due to the low solids content. Wide-angle X-ray further subcategorized the phases based on polymorphic divisions of the hydrocarbon side chain packing. In all, six distinct phases are reported, ranging from lamellar crystals, to liquid crystals to what appears to be a lipid glass.  相似文献   

8.
This study investigated the role of flaxseed meal (FSM), a rich terrestrial source of ω-3 fatty acids, in the alteration of the fatty acid profile and metabolism, health indices, physicochemical properties, and sensory quality of broiler chicken meat. The broiler chickens were fed 100 g FSM kg−1 diet for different time periods (1, 2, 3, 4, and 5 weeks). The results revealed that 100 g FSM feeding in broiler chickens for at least 3 weeks increased (P < 0.01) the EPA, DHA, MUFA, PUFA, ω-3 PUFA, and ω-6 PUFA of broiler chicken meat with the corresponding decrease in palmitic acid, stearic acid, and SFA content. 100 g FSM feeding up to 3 weeks has increased the Δ9-desaturases (P < 0.05), thioesterase index (P < 0.01), and Δ5-desaturase + Δ6-desaturase activity (P < 0.01) along with an improvement in health indices (P < 0.01) of chicken meat. Similarly, a reduction in meat cholesterol and fat content of thigh meat (P < 0.01) was observed by feeding 100 g FSM for at least 3 weeks with no effect on the pH, color scores, and sensory evaluation of broiler chicken meat. The water-holding capacity (WHC) and extract release volume (ERV) decreased, whereas, drip loss of meat increased (P < 0.01) due to the feeding of 100 g FSM beyond 3 weeks. Thus, this study concluded that 100 g FSM feeding for 3 weeks in broiler chickens significantly improves the fatty acid profile, lipid metabolism, and health indices of meat, without compromising the physicochemical properties of broiler chicken meat.  相似文献   

9.
Today, tocopherols serve as the industrial standard antioxidant protection for fish oil omega-3 concentrates. Synergistic interactions between tocopherols, ascorbyl palmitate and natural polyphenols extracted from plant sources have been demonstrated in model systems. The main goal for this work was to develop a mix of such antioxidants with improved efficacy in the context of preserving industrial marine oil concentrates. The antioxidant formulation comprises tocopherols, ascorbyl palmitate, rosemary extract and green tea catechins. Part of the scope was to develop a method for dissolving green tea catechins in oil. The key element of the method is to introduce green tea on a lipid insoluble carrier when dissolving the extract in the oil, and thereafter remove the carrier by filtration. The antioxidant mix was tested against tocopherol in omega-3 concentrates of minimum 300 mg/g eicosapentaenoic acid (EPA) plus 200 mg/g docosahexaenoic acid (DHA) in the form of triacylglycerides and ethyl esters. The mix was superior compared to tocopherols in suppressing both primary- and secondary oxidation. Weight increase measurements of oil in contact with air correlated well with standard oxidation tests within individual samples and the method was considered simple and useful for monitoring oxidation in omega-3 concentrates.  相似文献   

10.
Human milk fat (HMF) is a perfect nutritional source that includes all the required ingredients which are necessary for the growth of infants up to 6 months. Although its composition may differ among mothers or during lactation stage, its unique triacylglycerol (TAG) structure remains constant which is characterized by the presence of palmitic acid (PA) at the sn‐2 position. Previous reports provided convincing information of higher PA and calcium absorption and efficient use of dietary energy when at this specific position in the TAG moiety than when PA is at the sn‐1,3 positions. During the design of structured lipids (SLs) intended for infant nutrition, this unique property is taken into consideration. Human milk fat substitutes (HMFS) enriched with important fatty acids such as omega‐3 and omega‐6 fatty acids are intended to better mimic the functions of HMF as well as provide associated health benefits. The use of microencapsulation technology and novel technologies such as ultrasound technology in conjunction with SL production and enzyme‐catalyzed reactions are evolving and ongoing issues in infant formula production. Therefore, further studies should be directed towards new process improvements in order to increase the functional properties and oxidative stabilities of HMFS. Novel technologies in lipid biotechnology related to HMFS preparation should also be explored.  相似文献   

11.
The composition of the oil and protein contents of eight Lagenaria siceraria varieties was characterized in order to evaluate their suitability as a source of edible oil and protein. The physicochemical properties and fatty acids of seed oils were determined. The oil yield ranged from 24.11 to 26.32 %. The refractive indices and relative densities of the oils fell within the narrow ranges of 1.464–1.468 and 0.857–0.907 g/cm3, respectively. The saponification value ranged from 158.48 to 179.52 mg KOH/g, unsaponifiable matter was between 0.749 and 0.937 %, and the peroxide values were lower than Codex values for vegetable oils. The principal fatty acids were linoleic (62.1–67.9 %), oleic (11.54–15.46 %), palmitic (12.13–14.03 %), and stearic (6.71–7.71 %) acids. Low linolenic acid levels were also observed (<1 %) within the range of 0.32–0.44 %. The major essential amino acids were arginine (2.04–3.77 g/100 g), leucine (1.245–1.726 g/100 g), phenylalanine (0.803–1.396 g/100 g), and lysine (0.921–1.383 g/100 g). The non‐essential amino acids were glutamic acid (2.5–4.37 g/100 g), aspartic acid (1.39–2.36 g/100 g), serine (0.69–1.19 g/100 g), glycine (0.79–1.37 g/100 g), alanine (0.72–1.37 g/100 g), and proline (0.63–1.02 g/100 g). Nine minerals (Na, Ca, Mg, K, Cu, Fe, Mn, Zn, and P) were determined with significant (p < 0.05) differences. The studied oils showed promising results and can be used in the food, cosmetics, and pharmaceutical industries. This is the first study on the eight L. siceraria seed varieties grown in Sudan, opening the way for further studies on these seeds.  相似文献   

12.
We investigated organogel formation in dispersions of CW in safflower oil (SFO). Candelilla wax (CW) has as its main component hentriacontane (78.9%), a n-alkane with self assembly properties in organic solvents (i.e., vegetable oils). Results showed that, independent of the cooling rate (i.e., 1 °C/min and 10 °C/min) and gel setting temperature (T set), the CW organogels observed a thermoreversible behavior. This was evaluated by the behavior of thermal parameters that characterized organogel formation (gelation temperature, T g; heat of gelation, ΔHg) and melting (melting temperature, T p; heat of melting, ΔHM) after two heating-cooling cycles. For a given CW concentration (i.e., 0.5, 1.0, and 3%), the magnitude of ΔHM and T p and the structural organization of the organogel, depended on the cooling rate, the thermodynamic drive force for gelation, and the annealing process occurring at high Tset (i.e., 25 °C). At T set of 25 °C the microplatelet units that formed the organogel aggregated as a function of storage time, a process that resulted in an increase in organogel hardness. In contrast, at T set of 5 °C annealing occurred in a limited extent, but gels had higher solid fat content and microplatelet units of a smaller size than the gels obtained at 25 °C. The result was a three-dimensional network with greater hardness than the one obtained at 25 °C. The 3% CW organogels showed no phase separation up to 3 months at room temperature, with textures of potential use by the food industry.  相似文献   

13.
The performance of solid lipid nanoparticles is often modified by the addition of small amounts of liquid oil. The effects of added liquid lipid (tetradecane, C14) on the distribution and reactivity of the spin probe 4-phenyl-2,2,5,5-tetramethyl-3-imidazoline-1-oxyl nitroxide (PTMIO) in solid lipid nanoparticles (eicosane, C20) were investigated as a function of storage time and temperature. Emulsions prepared with blends of C14:C20 (100 % C14, 90 % C20, 99 % C20, and 100 % C20) and stabilized by sodium caseinate (1 wt%) were stored at 21.5 °C or 5 °C for 5 or 24 h prior to EPR analyses. In the liquid C14 droplets the PTMIO partitioned between the droplet and aqueous phases (70 and 30 %, respectively) independent of storage conditions. However, the proportion of probe in droplets decreased with increasing crystalline C20 concentration. The fraction of PTMIO in droplets containing C20 decreased in the following sequence: 5 h at room temperature >24 h at room temperature >24 h at refrigerated temperature and was lower in droplets with a higher proportion of C20. The residual PTMIO in semicrystalline droplets has higher polarity and lower mobility than PTMIO in liquid oil droplets suggesting it is in a layer surrounding the crystalline lipid core, and partly immobilized by interaction with the surface layer. The model of PTMIO distribution was consistent with the kinetics of PTMIO reduction by aqueous ascorbate ions.  相似文献   

14.
Flaxseeds were roasted at 1150 W/m2 radiation intensity with short and medium wave infrared (IR) emitters for specific durations, which provided good visual and sensory quality. The effects of IR roasting on color properties, hydrogen cyanide (HCN) content, tocopherols and fatty acid composition of the flaxseed and flaxseed oil were investigated. Further, flaxseeds were stored for 6 months and free fatty acid content and peroxide values were followed at 1-month intervals to understand the effect of IR treatment on hydrolytic and oxidative stability. HCN content of the flaxseeds was reduced up to 59% with IR roasting. Tocopherol content of the IR roasted flaxseed oil was higher than that of the control. No notable variation was observed in fatty acid composition with regard to IR treatment. Free fatty acid content of IR roasted flaxseeds did not increase during storage, while peroxide value of the seeds significantly increased up to 95 mEq O2/kg oil.  相似文献   

15.
The need for novel and diverse sources of protein to feed the growing world population is urgent and stark. At the same time, peoples’ eating habits and values are also changing, with more consumers considering alternatives to traditional sources of protein. Novel protein sources not only need to provide essential amino acids and nutrition, but also cater to taste, convenience, cost economics, and personal needs. They also need to be ethically produced, with a smaller environmental footprint, and when feasible, closer to consumer. Insect protein has been researched intensively in recent years with promises to best fulfill these needs. As the insect protein field and industry are expanding and getting more mature at this stage, this review summarizes their properties and applications within the context of the food and feed industry. The important functional properties that make insect proteins useful are also discussed.  相似文献   

16.
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18.
The oxidation of vegetable oils is generally treated as an apparent first order kinetic reaction. This study investigated the deterioration of crude palm oil (CPO), refined canola oil (RCO) and their blend (CPO:RCO 1:1 w/w) during 20 h of successive deep‐fat frying at 170, 180 and 190 °C. Kinetics of changes in oil quality indices, namely, free fatty acid (FFA), peroxide value (PV), anisidine value (p‐AV), total polar compounds (TPC) and color index (CI) were monitored. The results showed that FFA and PV accumulation followed the kinetic first order model, while p‐AV, TPC and CI followed the kinetic zero order model. The concentration and deterioration rate constants k, increased with increasing temperatures. This effect of temperature was modeled by the Arrhenius equation. The results showed that PV had the least activation energies Ea (kJ/mol) values of 5.4 ± 1 (RCO), 6.6 ± 0.7 (CPO) and 11.4 ± 1 (blend). The highest Ea requirement was exhibited by FFA with a range of 31.7 ± 3–76.5 ± 7 kJ/mol for the three oils. The overall Ea values showed that the stability of the blend was superior and not just intermediate of CPO and RCO. The correlation of the other oil quality indices with TPC indicated a positive linear correlation. The p‐AV displayed the strongest correlation, with mean correlation coefficient rs of 0.998 ± 0.00, 0.994 ± 0.00 and 0.999 ± 0.00 for CPO, RCO and blend, respectively.  相似文献   

19.
植物精油的研究开发新进展   总被引:2,自引:0,他引:2  
张东峰 《河北化工》2008,31(2):10-12,40
植物精油是一类纯天然的植物提取混合物,化学组成比较复杂.迄今为止,其在食品、医药、果蔬保鲜、日常用品、人体保健等方面得到了广泛的开发和利用.概述了植物精油及其单组分的研究利用新进展.预计不久的将来植物精油在人类生活中必将具有广阔的应用前景.  相似文献   

20.
An optimized one-step extraction and methylation method (OSE) for the determination of n-3 fatty acid levels in microencapsulated fish oil products has been described. Validation of the method for the food ingredient powder MEG-3® (a commercial microencapsulated fish oil product manufactured by Ocean Nutrition Canada Ltd, with a gelatin shell matrix) has been demonstrated and compared to a method that combines enzymatic digestion of the shell material, gravimetric determination of released oil payload and an official method of fish oil analysis. Excellent agreement between the two methods was also achieved using a microencapsulated standard of pure ethyl palmitate. The OSE method was applied to an infant formula containing microencapsulated fish oil powder and is shown to be a valid method for such dry powdered foods.  相似文献   

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