摘要:

AbstractDie Methylester der ungesättigten Fettsäuren 10‐Undecensäure, Ölsäure und (E)‐10‐Eicosendisäure wurden in einer thermischen En Reaktion bei 190°C mit Maleinsäureanhydrid umgesetzt. Die Monoadditionsprodukte wurden isoliert und ihre Stereochemie mittels1HNMR‐ und13C‐NMR‐Spektroskopie e

ISSN:0931-5985    

DOI:10.1002/lipi.19940960901

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractMilk fat from 440 butter samples obtained from more than 20 Northern German milk collection areas was extracted and the solid fat content (SFC) determined at 7 temperatures between 0 and 30°C using nuclear magnetic resonance spectrometry. Further, all milk fats were analyzed gas chromatographically for their triglyceride composition. Using a multiple regression analysis triglyceride formulae have been computed which enable the SFC‐values to be theoretically calculated at all 7 measuring temperatures. The standard deviations between experimental and theoretical SFC‐values at temperatures between 0, 5…, 30°C ranged between 0.88 and 0.38% (r = 0.99990 and 0.99682). Also between the fatty acids C18:1 (oleic acid with isomers), C16 (palmitic acid) resp. C16/C18:1 and the SFC‐values measured at 0°C relationships have been established (r = ‐0.95, 0.93 and 0.93, respectively). Since the expenditure in time necessary for gas chromatographic triglyceride analysis by using simultaneously 2 columns can be reduced to 4 ‐ 5 min and, in addition, extrelut columns allow a very fast isolation of fat from milk for gas chromatographic analyses, rapid characterization of milk fat regarding solid fat contents or also milk fat hardness is feasible by means of triglyceride analysis. Besides the SFC‐values a number of other milk fat parameters, such as iodine number, melting point, refraction index etc. can be determined using the same trigl

ISSN:0931-5985    

DOI:10.1002/lipi.19940960902

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractThe mass spectrometrical fragmentation patterns of the 4,4‐dimethyloxazoline derivatives (DMOX) of the studied oxo fatty acids are easily to understand. The oxo group positions can be assigned unequivocally. The spectra are similar to those of the corresponding pyrrolidide derivatives. Since DMOX derivatization proofed to be good for the GC‐MS analysis of epoxy fatty acids as well, the method could be interesting for studies on oxidized fatty acids, as w

ISSN:0931-5985    

DOI:10.1002/lipi.19940960903

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractLife Cycle Analysis (LCA) of Renewable Raw Materials Using “Palm Oil” as an ExampleRenewable raw materials provide ecological advantages such as renewability, protection of limited resources, unlimited availability, ease of decomposition of end‐products, as well as reintegration of material. In the public discussion the above‐mentioned characteristics are increasingly examined from an ecological point of view. Do they require too much fertilizer and pesticides? Are there any impacts on the ecological system such as emissions to the groundwater and damages by erosion? Within certain limits ‐ as the social‐economic sector is not taken into account ‐ the LCA‐method proves to be a means of investigation whereby ecological processes can be evaluated in a comprehensive way from “cradle to grave”. It is, however, stressed that LCA is not always carried out uniformly. Especially the LCA of renewable raw material shows considerable deviations resulting from the different evaluation of agricultural residue. The term “waste” in agricultural and industrial systems is discussed. By using the example of the Malaysian agricultural production of oil palms in plantations and palm oil in oil mills it is demonstrated that there exists an almost closed recycling system of all the agricultural residue and by‐products. Furthermore, the paper deals with the closed CO2loo

ISSN:0931-5985    

DOI:10.1002/lipi.19940960904

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractEdible oils are desterolized in order to render them “undetectable” when admixed to other oils. Such frauds remain, however, detectable by the olefinic degradation products of the sterols: the degradation products approximately have the composition of the sterols they originate from. Presence of campestatriene (degraded brassicasterol) reveals the presence of desterolized rapeseed oil. The ratio of the degradation products of sitosterol and campesterol is a sensitive indicator for desterolized sunflower, soybean, palm, or grapeseed oil in oils of low campesterol content, such as olive and walnut oil. Analyses were performed by on‐line coupled

ISSN:0931-5985    

DOI:10.1002/lipi.19940960905

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractComparing the phase diagrams of three binary soap systems (soap: K‐laurate = KC12) KC12/glycerol, KC12/ethylene glycol and KC12/butylene glycol we found alterations in the types of phase diagrams that depend on the protic solvents. A different polymorphism in the binary systems were observed which was dependent on the solvent. In the system KC12/glycerol: C ↔ G ↔ H ↔ L ↔ S (C = crystalline phase, G = gel phase, H = hexagonal phase, L = lamellar phase, S = isotropic solution), in the binary system KC12/E: C ↔ G ↔ L ↔ S, in the binary system KC12/B: C ↔ G ↔ L ↔ S. The differences in number, position, extension and sequence of occurring mesophases are a function of the composition in the binary systems and of the temperatures. We came to the conclusion that the influence, which the solution medium exerts on the formation of structures in the binary systems, is very di

ISSN:0931-5985    

DOI:10.1002/lipi.19940960906

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractHighly significant correlations were found to exist between the refractive index of fish oils and their content of eicosapentaenoic acid, the sum of eicosapentaenoic and docosahexaenoic acid and the total polyunsaturated fatty acids. The refractive index of a fish oil can be used therefore as an indicator of the content of the abovementioned fatty acids.

ISSN:0931-5985    

DOI:10.1002/lipi.19940960907

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

摘要:

AbstractStoffeigenschaften sowie deren Temperaturabhängigkeit spielen in technischen Prozessen eine wichtige Rolle. So werden in dieser Arbeit die Temperaturabhängigkeiten der Stoffeigenschaften Dichte und Viskosität sowie die Temperaturabhängigkeit des Fließverhaltens von Sojaöl und epoxidiertem Sojaöl untersucht. Außerdem wird der Einfluß der Zusammensetzung auf diese Größen in Mischphasen b

ISSN:0931-5985    

DOI:10.1002/lipi.19940960908

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY