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1.
The lipid fraction of the deep water fish species orange roughy (Hoplostetbus atlanticus), black oreo (Allocyttus sp.) and small spined oreo (Pseudocyttus maculatus) had wax esters with even carbon numbers over the range C30 to C46 as the major components. The component acids and alcohols of the wax ester fraction were analyzed by gas liquid chromatography and compared with those of jojoba and sperm whale oils. Orange roughy oil was refined and deodorized and its chemical, physical and mechanical properties were determined. Hydrogenation of orange roughy oil produced a range of white crystalline waxes with melting points between 34 and 66 C. The characteristics of these waxes were very similar to those of hydrogenated jojoba oil and spermaceti. Lubricant tests performed on sulfurized orange roughy oil indicated it is comparable to sulfurized jojoba and sperm whale oils as an extreme-pressure additive in lubricants. The results show a sound technical basis on which to consider an industry based on orange roughy oil and the oreo oils as replacements for sperm whale oil and as substitutes for jojoba oil. Applications for the oil could be in the cosmetic and high-grade lubricant fields, the waxes in the polish, textile, cosmetic and pharmaceutical industries and the sulfurized derivative of orange roughy oil in the lubricant industry.  相似文献   

2.
Laboratory and simulated in-use lubricant tests were performed on sulfurized jojoba oil and on reference sulfurized sperm whale oil. Data from these comprehensive tests indicated sulfurized jojoba oil prepared from heat-treated filtered oil to be comparable or superior to sulfurized sperm whale oil as an extreme-pressure additive for motor oils, gear lubricants, and automotive transmission fluids.  相似文献   

3.
Summary The Korpaczy modification of the Stamm reaction for detecting rancidity in fats has been applied to a variety of fats and oils, including hog and beet fat, cottonseed oil, a number of other vegetable and seed oils, and a group of marine oils. This reaction has been shown to be generally inapplicable to vegetable, seed and marine oils but applicable to lard and beef fat.  相似文献   

4.
The influence of water on the interactions between fat and sugar crystals dispersed in triglyceride (vegetable) oils was qualitatively estimated from sedimentation and rheological experiments. The experiments were performed both with and without food emulsifiers (monoglycerides and lecithins) present in the oil. The effects of minor natural oil components (nontriglycerides) on the interactions and on emulsifier adsorption to the crystals were examined by comparing a commercial refined oil and a chromatographically purified oil. The results show that water generally increases the adhesion between fat and sugar crystals in oils and also increases the surface activity of the oil-soluble food emulsifiers. Minor oil components give a small increase in the adhesion between fat and sugar crystals in oils, but do not influence the adsorption of food emulsifiers in any systematic way.  相似文献   

5.
Vegetable oils that are important to the chemical industry include both edible and industrial oils, which contribute 24% and 13.5%, respectively, compared to 55% for tallow, to the preparation of surfactants, coatings, plasticizers, and other products based on fats and oils. Not only the oils themselves but also the fatty acids recovered from soapstock represent a several billion pound resource. Coconut oil is imported to the extent of 700-1,000 million pounds per year. Its uses are divided about equally between edible and industrial applications. Safflower oil has a relatively small production, but 15–25% of the oil goes into industrial products. Soybean oil, the major edible oil of the world, is produced in the United States at the rate of 11,000 million pounds per year with more than 500 million pounds going into industrial uses, representing 5% of the total production. Castor oil is imported to the extent of about 100 million pounds per year. Linseed oil production has declined drastically over the last 25 years but still amounts to about 100 million pounds per year. Oiticica and tung oils are imported in lesser amounts than castor and linseed oils. New crops that have industrial potential, as well as the traditional vegetable oil crops, include seed oils from crambe,Limnanthes, Lesquerella, Dimorphotheca, Vernonia, andCuphea plants. Crambe oil contains up to 65% erucic acid. Oil fromLimnanthes contains more than 95% of fatty acids above C18.Lesquerella oil contains hydroxy unsaturated acids resembling ricinoleic acid from castor oil.Dimorphotheca oil contains a conjugated dienol system.Vernonia oils contain as much as 80% epoxy acids. TheCuphea oils contain a number of short chain fatty acids. Of these, crambe,Limnanthes, andVernonia are probably the most developed agronomically. Competition between vegetable oils and petrochemicals for the traditional fats and oil markets has been marked over the past 25 years, but prices for petrochemicals have accelerated at a greater rate than those for vegetable oils; and, it is now appropriate to reexamine the old as well as the new markets for fatty acids.  相似文献   

6.
Oxidative Stability Index (OSI) of carbohydrate fatty acid polyesters, fat substitutes and vegetable oils were measured with the Omnion Oxidative Stability Instrument according to the new AOCS Standard Method Cd 12 B-92 (The Official Methods and Recommended Practices of the American Oil Chemists' Society, edited by D. Firestone, AOCS, Champaign, 1991). The stability of crude and refined, bleached and deodorized (RBD) vegetable oils (soybean, hydrogenated soybean and peanut) were determined at 110°C. In addition, OSI times for sucrose polyesters of soybean oil, butterfat, oleate:stearate and methyl glucoside polyester of soybean oil were determined in the absence and in the presence of 0.02 wt% antioxidants, [Tenox TBHQ (tertiary butylhydroquinone, Tenox GT-2 (from Eastman Chemical Products (Kingsport, TN); and vitamin E (from BASF, Wyandotte, MI)], and the results were compared with those of vegetable oils. Crude oils were most stable (20.4–25.9 h), followed by RBD oils (9.3–10.4 h) for soybean and peanut oils, respectively, and fat substitutes (3.8–6.8 h). Overall, Tenox TBHQ was the best antioxidant for improving the oxidative stability of both vegetable oils and fat substitutes. The sucrose polyester made with oleic and stearic acid was more stable than fat substitutes containing more polyunsaturated fatty acids, such as those from soybean oil, or from short-chain fatty acids, such as from butterfat. Antioxidants enhanced the stability of RBD oils (222% increase) and synthetic fat substitutes (421–424% increase) more than that of crude oils (33% increase). The shapes of the induction curves, not the actual OSI times for fat substitutes and vegetable oils, were similar and sharply defined.  相似文献   

7.
选用椰子油、棕榈油、橄榄油、山茶油、乳木果油、甜杏仁油、美藤果油和霍霍巴油8种植物油脂为原料,采用冷制工艺制作成3组不同含油量的植物油脂手工皂,研究了不同植物油脂对冷制皂入皂特性的影响,并对植物油脂复配制作的冷制皂进行肤感感官评价。结果表明,植物油脂的种类和含量对冷制皂的p H值影响不大,对其他入皂特性均有影响。椰子油冷制皂硬度高、起泡性强且泡沫丰富、Trace time短,与不饱和植物油脂复配入皂有助于缩短制作冷制皂的Trace time,提高冷制皂的硬度和起泡能力;山茶油、甜杏仁油和橄榄油入皂有助于起泡;橄榄油入皂有助于提高冷制皂的泡沫稳定性;乳木果油和霍霍巴油入皂起泡能力较差;美藤果油入皂滋润度高、泡沫细腻、洗感舒适、肤感评价最佳。  相似文献   

8.
The predominating molecular species in jojoba oil iscis-13-docosenylcis-11-eicosenoate (erucyl jojobenoate), ranging from 31% to 45% of the extracted seed oil. Other alcohol/acid combinations contribute to the C42 molecular chain length so that this fraction constitutes a low of 41% to a high of 57% of the total wax esters. The positions of the exclusivelycis ethylenic bonds in the alcohol and acid moieties of the wax esters are 99% ω-9 and 1% ω-7. Only 2% of the alcohol and acid moieties were saturated when analyzed after saponification of the oil. Triglycerides were detected by gas chromatography in all of the more than 200 natural jojoba oil samples tested, a few of which had substantially more than the normal 1%. Among the many uses of jojoba oil cited here, the two most promising are the sulfurized oil as extreme-pressure/extreme-temperature lubricant additive and the natural or refined oil formulated into cosmetic products.  相似文献   

9.
Vegetable oils are a renewable and an environmentally friendly alternative to petroleum-based oils in lubrication and other important application areas. Vegetable oils fall into two broad chemical categories: triesters (or TG) and monoesters. Most vegetable oils are triesters of glycerol with FA, whose characteristics are dependent on the chemistry and composition of the FA residues. A small percentage of vegetable oils are monoesters of long-chain FA and fatty alcohols of varying chemistries. In this work, the free energy of adsorption (ΔG ads) of safflower (SA), high-oleic safflower (HOSA), and jojoba (JO), methyl oleate (MO), and methyl palmitate (MP) on steel were investigated. SA and HOSA are TG of vegetable oils with FA residues of radically different degrees of unsaturation. JO is a monoester vegetable oil. ΔG ads is one of the major factors affecting the boundary friction properties of lubricant ingredients. ΔG ads was found to increase in the order: HOSA≤SA<JO<MO≤MP. The results are consistent with the degree of functionality and other chemical properties of the oils studied.  相似文献   

10.
A high performance liquid chromatographic (HPLC) method has been developed to analyze oxidative and polymerized decomposition products in commercial vegetable oils and heated fats. The oil was passed through a SEP-PAK where the minor constituents were concentrated. The SEP-PAK was eluted with hexane-ether 1:1 (v/v), and 2-propanol. The first eluate contained unsaponifiables and neutral lipids, and the second eluate contained the more polar oxidative and polymerized decomposition products. The second eluate was analyzed by normal phase HPLC. Five commercial vegetable oils were analyzed, and similarities and differences were observed. Four soybean oil samples from different manufacturers also showed differences. Soybean oil heated at 185°C was collected periodically and analyzed. As the heating time increased, the oxidation and polymerization products also increased. Used frying fat samples from a commercial fried chicken manufacturer were analyzed. The frying oil quality reached an equilibrium during three days of operation, because the oil lost in frying was replenished daily with fresh shortening.  相似文献   

11.
Recently, bio-derived materials such as vegetable oils are significantly employed in lubricating oil formulations due to its high flash point, high lubricity, low evaporation loss, renewability, biodegradability, and eco-friendliness when compared to mineral oil. We investigated the performance of seven poly(alkyl lactate acrylate)s as viscosity modifiers in two vegetable oils, namely, coconut oil and sunflower oil, which differ in the percentage of polar compounds and degree of unsaturation. Poly(alkyl lactate acrylate)s having alkyl as hexyl to dodecyl group in different concentrations between 1 and 2 wt% were added to coconut and sunflower oil and parameters such as thickening power or Q factor, kinematic viscosity (μ), and viscosity index (VI) were calculated. The μ values at 40°C and 100°C of vegetable oils studied were lower than commercially available SAE20W40 engine oil, but the VI of coconut and sunflower oil was higher by about 22%. Value of Q factor higher than 1, indicated that these poly(alkyl lactate acrylate)s were VI improvers. VI increased with increase in the polymer concentration in both the vegetable oils. The length of the alkyl side chain of these polymers and the polarity of vegetable oil had predominant effect in determining the values of VI of vegetable oils. By using these polymer additives, VI was improved by 85.5% in coconut oil and by 61.7% in sunflower oil. Varying the concentration and alkyl group of these additives, one can largely modify the viscosity ranges enabling them to be used in different lubricating applications.  相似文献   

12.
The addition of 0.02% ascorbyl palmitate (AP) reduced color development of frying fat (animal fat/vegetable oil [A-V] shortening) and vegetable oil (partially hydrogenated soybean [V-S] oil) in simulation studies. It also reduced peroxide values, development of conjugated diene hydroperoxides (CDHP) and their subsequent degradation to volatile compounds, such as decanal and 2,-4 decadienal, indicating that AP has the ability to inhibit thermal oxidation/degradation of frying fats and oils. A commercial french fry fat had lower CDHP values compared to A-V fat in simulated studies, and fried chicken oil had lower CDHP values than the V-S oil. Peanut oil had higher thermal stability than the other fats and oils.  相似文献   

13.
Biodiesel is a promising alternative diesel fuel obtained from vegetable oils, animal fats, or waste oils by transesterifying the oil or fat with an alcohol such as methanol. In an extension of previous work, fiber-optic near infrared spectroscopy was used to quantitatively monitor the transesterification reaction (6-L scale) of a vegetable oil (soybean oil) to methyl soyate. The results were correlated with 1H nuclear magnetic resonance spectroscopy. The method described here can be applied to the transesterification of other vegetable oils.  相似文献   

14.
The ability of mycelium-bound lipase of a locally isolated Aspergillus flavus to modify the triglyceride structure of vegetables oils was studied. The catalysis involved the acidolysis of vegetable oils, such as palm olein, coconut oil, cotton-seed oil, rapeseed oil, corn oil and soybean oil, with selected fatty acids (FA). The reactions were followed against time, and the percentages of FA incorporated were determined by gas chromatography. Percentage of FA incorporated after 20-h reaction was in the range of 13 to 18%. Reaction between cottonseed oil with lauric acid gave the highest percentage of incorporation (18%), followed by soybean oil with lauric acid (16%) and coconut oil with oleic acid (16%). The results indicated that the hydrolytic affinity of A. flavus lipase demonstrates an acyl group specificity toward short-chain FA (C8–C10). Changes in triglyceride profiles of each oil were also monitored by reverse-phase high-pressure liquid chromatography. In all products, there were increases in the concentrations of several existing triglycerides and formation of new triglycerides. The melting points of all acidolyzed vegetable oils were determined by differential scanning calorimetry, and significant changes in melting profiles were noted.  相似文献   

15.
The factice gelation time for meadowfoam oil, along with hardness, color, acetone extract and free sulfur content of the gelled products were compared with gelation time and product properties of factice prepared from seed oils of rapeseed, crambe, soybean, castor,Lesquerella and jojoba. The effect of additives, specifically zinc oxide, magnesium oxide, triethylamine, dicyclohexylamine, 2-mercaptobenzothiazole and iodine, was also investigated. Both white and brown factices could be prepared from meadowfoam oil and their properties were equivalent to or better than those from high erucic acid rapeseed oil used commercially for the highest quality factice. Presented at the Association for the Advancement of Industrial Crops 1st Annual Conference in Peoria, Illinois, October 2–6, 1989.  相似文献   

16.
Fat blends, formulated by mixing a highly saturated fat (palm stearin or fully hydrogenated soybean oil) with a native vegetable oil (soybean oil) in different ratios from 10:90 to 75:25 (wt%), were subjected to chemical interesterification reactions on laboratory scale (0.2% sodium methoxide catalyst, time=90 min, temperature=90°C). Starting and interesterified blends were investigated for triglyceride composition, solid fat content, free fatty acid content, and trans fatty acid (TFA) levels. Obtained values were compared to those of low- and high-trans commercial food fats. The interesterified blends with 30–50% of hard stock had plasticity curves in the range of commercial shortenings and stick-type margarines, while interesterified blends with 20% hard stock were suitable for use in soft tubtype margarines. Confectionery fat basestocks could be prepared from interesterified fat blends with 40% palm stearin or 25% fully hydrogenated soybean oil. TFA levels of interesterified blends were low (0.1%) compared to 1.3–12.1% in commercial food fats. Presented at the 88th AOCS Annual Meeting and Expo, May 11–14, 1997, Seattle, Washington.  相似文献   

17.
A review is presented of edible vegetable oil purity criteria developed at the Leatherhead Food Research Association. Most of the work involved accurate determination, by modern GLC techniques, of the fatty acid compositions of oils extracted in the laboratory from oilseeds of known origin and history. All of the main production areas throughout the world were represented in the collection of over 600 samples of commercial oilseeds. No botanial curiosities or hand picked specimens were included as the work related to commercially available edible oils. The fatty acid compositions of the major vegetable oils are reviewed, and the influence this had on the revision of Codex Alimentarius Fats and Oils Specifications is discussed. The development of purity criteria based on the composition of fatty acids at the triglyceride 2-position, triglyceride compositions by high temperature GLC, sterol compositions and tocopherol concentrations are also reviewed. In the case of maize oil a significant new development is the authentication of the oil by stable carbon isotope ratio measurement. The possibilities of this exciting new technique are reviewed in the light of 40 results on maize oils of various origins, together with over 60 results on a selection of other oils and fats.  相似文献   

18.
Dialkyl phosphonates of vegetable oils were synthesized by reacting soybean (Soy) and high oleic sunflower (HOSuO) oils with dialkyl phosphites. Dimethyl, diethyl, and di-n-butyl phosphites were used in the synthesis and the resulting phosphonates were obtained in good yields and thoroughly characterized. All six phosphonates displayed poor solubility in polyalphaolefin-6; and four displayed adequate solubility (> 20% w/w) in HOSuO. Evaluation as anti-wear (AW) additives in HOSuO base oil blends showed the biobased phosphonates have similar coefficient of friction and similar or better wear scar diameter than zinc dialkyl dithio phosphates (ZDDP). It is concluded that vegetable oil phosphonates provide a promising biobased alternative to ZDDP and other commercial petroleum-based AW additives currently used in lubricant formulations.  相似文献   

19.
Objectives of this study were (i) to incorporate short-chain fatty acids (SCFA) in vegetable oils to obtain a bland product that could be used as a milk fat substitute in cheese making and (ii) to improve the methods for fatty acid analysis of vegetable oils modified with SCFA. Short-chain triglycerides (SCTG) were synthesized by esterifying SCFA with glycerol, and using a toluene azeotrope to remove the water of esterification. SCFA from two sources were used: (i) commercial acids and (ii) acids isolated by double distillation of milk fat methyl esters. The SCTG had a bitter, unacceptable flavor, but after interesterification with high-oleic sunflower oil (HOSO) and deodorization, the flavor was quite acceptable. SCTG were incorporated into HOSO at 100 and 120% of the levels found in the milk fat, by sodium methoxide-catalyzed interesterification. For fatty acid analysis, milk fat and simulated milk fat were converted to their decyl ester derivatives and analyzed by gas chromatography without further purification. The method was accurate and rapid for fatty acid analysis of fats containing a wide range of fatty acid chain lengths. All modified HOSO gave bland and acceptable flavors and had a SCFA composition close to that of milk fat. Results from using the modified HOSO in cheese making are reported in a later paper.  相似文献   

20.
Determination of oxidative stability of different edible oils, fats, and typical fat products was made using the Rancimat method and the active oxygen method. Induction periods (IP) were recorded under controlled conditions at 110, 120, and 130 ± 0.1°C for all products and over a range of 100–160°C for selected fats. A general oil stability evaluation industrial shortenings and vanaspati to be the most stable fats, with IP ranging from 10.00 to 15.47 h. Margarine and butter samples (IP, 4.98–6.04 h) were also found to show fair oxidative stability. Among the extracted and open-market salad-grade cooking oils, rapeseed oil (IP, 4.10 h) and soybean oil (IP, 4.00 h) showed the highest oxidative stability, whereas Salicornia bigelovii oil (IP, 1.40 h) was the least stable. The induction periods of typical fat products ranged from 2.59 to 9.20 h. CV for four determinations were <5.2% for shortening and vanaspati products and <4.3% for various vegetable oils, margarine, butter, and typical fat products. Rancimat IP values obtained at 110, 120, and 130°C were 40–46, 20–25, and 9–13% of active oxygen method values, respectively, corresponding to a decrease in Rancimat IP by a factor of 1.99 with each 10°C increase in temperature. Similarly, in the temperature range 100–160°C, an increase of 10°C decreased the Rancimat IP by a factor of 1.99  相似文献   

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