Zur Fettsäurezusammensetzung von Mandelöl

The Fatty Acid Composition of Almond Oil - A Critical Discussion The range of fatty acid compositions found in various almond oils traded internationally sometimes does not correspond to the published permissible range in pharmacopeias (e.g., DAB 9). In the literature, there have been various reports of adulteration, but also of greater variability of almond fatty acid composition depending on strain and geographical provenience. The problem is discussed and a series of recent analytical data is presented.     

Quantitative Bestimmung der apolaren dimeren Fettsäuren in Fetten und Ölen

Quantitative Determination of Unpolar Dimeric Fatty Acids in Fats and Oils Fatty acids obtained by saponification of fats followed by removal of unsaponifiables and petroleum ether insoluble oxidized fatty acids, were treated to give urea-adducts. The mixture of fatty acids which did not form adducts was esterified and separated by thin-layer chromatography. It was shown by mass-spectrometry that the methyl esters of unpolar dimeric fatty acids occupied a definite zone in the chromatogram. The methyl esters of unpolar dimeric fatty acids can be quantitatively estimated by charring the chromatogram under standardized conditions and densitometry of the above zone, whereby a test substance is co-chromatographed for comparison. The relative standard deviation in the chromatography and densitometric determination was approximately 10%. The lower limit of detection was at 0.005% of the methyl ester of unpolar dimeric fatty acid. Using dimeric fatty acids lebelled with radioactive carbon, it was proved that approximately up to 90% of the unpolar dimeric fatty acids can be detected by this method.     

Biochemische und molekularbiologische Ansätze zur Veränderung der Fettsäurezusammensetzung des Rapsöls

Biochemical and Molecular Biological Approaches for Changing the Fatty Acid Composition of Rape Seed Oil For the technical usability of rape seed oil and uniform esterification of all three positions of the glycerol backbone with erucic acid is desired, which is not found in the varieties examined so far. Our enzymatic investigations revealed that this is especially due to the characteristics of the acyltransferase catalyzing the acylation of the C-2 position of the glycerol backbone. This enzyme is unable to utilize erucic acid as a substrate. The corresponding enzyme activity of Limnanthes douglasii, however, posseses the ability to incorporate erucic acid. To transfer this property to rape seed the corresponding gene has to be isolated. A gene isolation using antibodies or oligonucleotides requires the purification of the protein encoded by the gene, which up to now has failed. In parallel to our further efforts to purify the protein we have started to establish alternative methods of gene isolation based on the functional expression of cDNAs in microorganisms.     

Änderungen im Öl-Gehalt und in der Fettsäurezusammensetzung von in Ungarn angebauten ausländischen Sojabohnensorten

Changes in Oil Content and Fatty Acid Composition of Foreign Soybean Varieties Grown in Hungary Cultivation studies carried out for a period of 3 years on 16 varieties of soybean have shown that oil content of the bean decreased in each year. This was found, especially, for the varieties Ford and Harasoy in which the oil content dropped by an average of 20%, whereas in all other varieties the oil content decreased by an average of 16%. Studies on the fatty acid composition of the oil revealed that the contents of saturated fatty acids and those of linoleic and linolenic acids as well as their correlation varied. Based on the results one might assume that a decrease in the content of linolenic acid occurs not only in the case of a negative correlation between linoleic and linolenic acids but also in the case of a positive correlation. These observations were made especially with the varieties Avea-111, Hark and Traverse. It has been claimed in the literature that in breeding soybean a lower level of linolenic acid can be accomplished by promoting a negative correlation between linoleic and linolenic acids. This statement must be modified, since, according to present findings, even a positive correlation between linoleic and linolenic acids seems to promote the decrease in linoleic acid, provided the positive correlation is accompanied by a decrease in content of both the acids. Based on the cultivation studies, certain varieties of soybean can be selected for breeding.     

Untersuchungen zur kontinuierlichen Hydrierung von Ölen und Fettsäuren III Kinetik der Härtung freier Fettsäuren des Sojaöls

Investigations of the Continuous Hydrogenation of Oils and Fatty Acids III: Kinetic of Free Fatty Acid Hardening of Soya Bean Oil The kinetic of continuous hardening of free fatty acids of soya bean oil was investigated in a reactor with solid porous catalyst using the trickling procedure. Under the given arrangement and continuous hydrogen excess (continuous phase) hydrogenation of fatty acids follows the kinetic I. order. Temperature influences are much stronger using Ni-catalyst in ihe phase of equalized properties than using fresh catalyst. Pressure influences the reaction rate in both cases in a positive way. Its effect however in connection with temperature rise is much stronger with catalyst in the phase of equalized properties, that is the catalyst with lower activity.     

Vergleichende gaschromatographische Untersuchungen über die Fettsäurezusammensetzung von Schweineschmalz und Gänseschmalz

Comparative Gas Chromatographic Studies on the Fatty Acid Composition of Lard and Goose Dripping Comparative gas chromatographic studies on the fatty acid composition of lard and goose dripping revealed differences, especially in the content of stearic and oleic acids. The ratio of stearic to oleic acid was 0.39–0.60 (average 0.49) for lard and 0.08–0.13 (average 0.11) for goose dripping. When 10% lard was added to goose dripping the aforesaid ratio was 0.15–0.18 (average 0.17). Therefore the ratio of stearic to oleic acid can be taken as a basis for the detection of about 10% and onwards of lard in goose dripping.     

Über die Fettsäurezusammensetzung der Lipoide einiger Gewürze

Fatty Acid Composition of Lipids of Some Spices Fatty acid composition of lipids of ten fruit spices (pepper, pimento, red pepper, chillies, cumin-seed, coriander, celery, dill, cardamon and vanilla), one seed spice (nutmeg), one flower spice (clove), three herb spices (sage, origano, thyme), one leaf spice (laurel), one bark spice (cinnamon) and ginger was determined by gas chromatography after transesterification and compared with the known values. In the lipids of cardamon, vanilla, cinnamon, ginger and laurel, which have not been examined so far, palmitic, oleic and linoleic acids were found to predominate. In the lipids of pimento and clove which belong to the family of myrtaceae, C₁₈ fatty acids were predominant. Spices belonging to the family of labiates are characterized by a high linolenic acid content.     

Einfluß der Fettzufuhr und der Fettsäurezusammensetzung auf Mast- und Schlachtleistung sowie auf Parameter des Protein- und Lipidstoffwechsels beim Schwein

Influence of Fat Intake and Fatty Acid Composition on Fattening, Carcass Performance, and Protein and Lipid Metabolism of the Pig The influence of fat intake and fatty acid composition on the digestibility of the crude nutrients, deposition of protein and fat, in vitro fat synthesis from glucose and on several blood parameters has been studied in four experiments using 108 piglets and in a fattening study. In piglet experiment 1 (5%, 18% and 35% crude fat) and in piglet experiments 2 and 3 (2-7% soybean oil or lard) and 4 (12% sunflower oil or coconut oil) attempt was made to achieve, within each experiment, the same intake of digestible protein (DP) and metabolizable energy (ME). In fattening studies 2 and 3, the feed was given ad libitum. Replacement of carbohydrate energy by fat energy caused in all experiments a reduction in feed requirement, a lower insuline level, a lower fat synthesis from glucose and a higher fat deposition, whereas the type of dietary fat distinctly affected the fatty acid composition of the back fat.     

Untersuchungen zur kontinuierlichen Hydrierung von Ölen und Fettsäuren I: Verlauf des Austausches der Rohstoffe

Investigations of the Continuous Hydrogenation of Oils and Fatty Acids I: Course of Raw Material Exchange The authors investigated the speed of exchange from one raw material to another during continuously hydrogenation in the system of trickling procedure of a continuous current reactor with solid catalyst layer. Pelletted Ni-catalyst with a Ni-content of 48.1% and a degree of reduction of 49% was used. The nearly complete exchange of sunflower oil for oleic acid and vice versa was reached by use of 2.5 to 3 fold acid or oil volume referred to catalyst layer volume.     

Gegenstrom-Fallfilm-Treibdampfdestillation mittels eines von außen aufgezwungenen Temperaturfeldes zur wirksamen Desodorierung von Fettsäuren und Speiseölen

Countercurrent Falling Film Steam Distillation Using Externally Applied Temperature Field for Efficient Deodorization of Fatty Acids and Edible Oils The impact of externally applied temperature field on steam deodorization in countercurrent film flow is discussed. Wavelike movement of a film flowing downwards vertically, in combination with additional film movement caused by lateral heat flow, leads to continuous renewal of the surface. Consequently, volatile impurities present in minute amounts which contribute to flavour and taste, have ample opportunity during flow of the film to reach the surface of the film and get in direct contact with the stripping steam. This transfer is facilitated by additional wave-like movement of the falling film. It is to be expected, that this countercurrent deodorization process enables favorable utilization of stripping steam at minimum pressure drop and maximum saturation with the volatile substances responsible for taste and flavor. This means low energy cost in fully continuous operation at minimum contact times, which result in minimum thermal stress on the material treated.     

Untersuchungen zur kontinuierlichen Hydrierung von Ölen und Fettsäuren IV: Stoffübergang bei kontinuierlicher Hydrierung

Investigations of Continuous Hydrogenation of Oils and Fatty Acids IV: Migration of Material During Continuous Hydrogenation Material migration takes place more or less in the velocity of the process in every heterogeneously catalyzed reaction. Above all hydrogenation of free fatty acids or fatty acids bound in triglycerides in the three phase system can make material migration valid. The effect of material migration on the reaction kinetic, especially by using high-active catalysts, was verified in a continuous hydrogenation system according to the trickling procedure. The effect of pressure increase up to 0.5 MPa is much higher than in the range of 1-2 MPa. The values of the material migration figure k_m were found in the range of 1.3 to 4.9 · 10⁴ cm · s^?1.     

Regioselektive C-H-Funktionalisierung von Fettsäuren und Fettsäuremethylestern

Regioselective C-H-Functionalization of Fatty Acids and their Methyl Esters Fatty acids and thier methyl esters can be chlorinated preferentially at the terminal methylene groups with N-alkylchloroamines in sulfuric acid. With capric acid and its methyl ester the optimal reaction conditions for the selective chlorination were elaborated and then transferred to longer fatty acids up to stearic acid. The influence of the solvent, the temperature and the nature of different chlorinating reagents on the selectivity was studies. The capillary GC/MS-analysis of the isomeric chlorinated fatty acids is described.     

Veränderungen der Fettsäurezusammensetzung von Lipidfraktionen aus Kartoffeln während der Lagerung

Alterations in Fatty Acid Composition of Lipid Fractions from Potatoes During Storage Fatty acid composition of total lipids of the lecithin and cephalin fractions were determind by gas chromatography in samples of fresh potatoes and those stored for 8 months in cold. Moreover, a method for isolation of the pure cephalin fraction is reported. In all the three fractions the percentage of linolenic acid increased during storage, whereas the content of linoleic acid decreased. Other fatty acids remained practically unchanged during the storage. An additional experiment in which powdered freeze-dried potatoes were stored under undesirable conditions showed, as expected, that the content of unsaturated fatty acids decreased strongly. The results are discussed.     

Untersuchungen zur kontinuierlichen Hydrierung von Ölen und Fettsäuren V: Grad der Ausnutzung der Ni-Katalysatoroberfläche bei der Hydrierung

Investigations of Continuous Hydrogenation of Oils and Fatty Acids V: Degree of Utilization of Ni-Catalyst Surface During Hydrogenation Hydrogenation of olive oil by Ni-catalyst according to the trickling process was investigated in a simplified reactor model. The tests were carried out by discontinuous proceeding on pelletted Ni-catalyst with elimination of the influences of the outer diffusion and by discontinuous proceeding with elimination of the outer and internal diffusion (powdery catalyst). The obtained values of the effective factor of the outer diffusion showed that the laminar film on the surface of the pellets causes a small resistance to mass transfer. The measurements of the effective factors of the internal diffusion showed that the degree of the exploit of the internal catalyst surface during hydrogenation of oils on pelletted Ni-catalyst is low.     

Hochdruckextraktion mit mehrstufiger fraktionierender Separation zur schonenden Gewinnung von Keimölen mit hochverdichtetem Kohlendioxid

High Pressure Extraction by Multi-Stage Fractionated Separation for Gentle Production of Corn Germ Oils with Highly Compressed Carbon Dioxide The supercritical extraction of conditioned corn germs with highly compressed carbon dioxide leads to extracts containing triglycerides and fatty accompanying substances. These are mainly water and free fatty acids but also tocopherols and sterols as well as dyestuff, flavors, and odorous substances. The quality of the corn germ oils extracted at gentle temperatures can be varied in a wide range by multi-stage separation. This is carried out either by a fractionation taking place in a multi-stage pressure cascade, or by a temporary fractionated separation, or by a combination of both processes. By means of a multi-stage high pressure extraction it is possible to yield oils nearly free from water and with a low content of free fatty acids as well as oils with a high content of tocopherols and sterols. The crude oils have the typical odor. They are light and absolutely clear and their colour ranges from a pale yellow up to a pale red. Furthermore, it is possible to fractionate the triglycerides. The process parameters pressure and temperature of the separators are of decisive importance for the fractionated separation.     

Untersuchungen zur kontinuierlichen Hydrierung von Ölen und Fettsäuren II Veränderungen Aktivität des Ni-Katalysators und ihre Beziehung zur Menge des gehärteten Rohstoffes

Investigations of the Continuous Hydrogenation of Oils and Fatly Acids II: Changes of Ni-Catalyst Activity and its Relation to the Amount of Hardened Raw Material It was the aim of the investigations to determine the influence of the raw material, which is to be hardened, on changes of activity of Ni-catalyst in trickle-bed reactor with solid bed. It could be established that the decrease of catalyst activity follows a hyperbolic function. The single parameters of this relation are proportional to reaction time, degree of catalyst reduction, storage period, temperature and pressure of hydrogenation. In the mentioned arrangement each NI-catalyst comes into a phase of equalized properties after a certain working period, which is characterized by fictious life span of 0.3–0.04g Ni/l raw material.     

Die Fettsäure-Zusammensetzung wirtschaftlich genutzter Brassica- und Sinapis-Öle

Fatty Acid Composition of Commercial Brassica and Sinapis Oils Oils of different brassica and sinapis varieties were analyzed in order to simplify the assessment of rapeseed oil and turnip rape oil. The results show that the fatty acid composition varies to a great extent, and therefore, rapeseed oil can no longer be defined on the basis of such a composition.     

Isolierung und Strukturaufklärung polyverzweigter Fettsäuren aus Fischöl

Isolation and Structure Determination of the Polybranched Fatty Acids from Fish Oil From a sample of sea fish oil, three saturated polymethyl branched fatty acids could be separated in pure state as methyl esters by using urea adduct, column chromatography and distillation methods. These could be identified as 4,8,12-trimethyl-tridecanoic acid, 2,6,10,14-tetramethyl-pentadecanoic acid and 3,7,11,15-tetramethyl-hexadecanoic acid, with the help of molecular weight determination, ultimate analysis, IR-, NMR- and mass-spectroscopy. The structures could be proved by synthesis. Many other branched chain fatty acids were synthesised for comparison. The synthesis and the infrared spectrums of these compounds are given in details.     

Kristallstrukturuntersuchungen an Fettalkoholen und Fettsäuren mit Elektronen- und Röntgenbeugung I

Studies on Crystal Structures of Fatty Alcohols and Fatty Acids Using Electron and X-Ray Diffraction I For the homologous series of even numbered saturated fatty alcohols from dodecanol (C₁₂H₂₅OH) up to hexacosanol (C₂₆H₅₃OH) the almost orthorhombic unit cells of the β₀₁-modifications could be shown by using electron and X-ray diffraction. Fouriersynthesis based on hkO-reflexes showed the presence of a β₀₂-form which has half the edge length c compared to the β₀₁-modification. Moreover, the eight γ₃- to γ₁₀-modifications of the various alcohols were detected. Unit cell parameters and the chain tilt were determined for all crystal structures. By X-ray diffraction, stearic acid was shown to exhibit five β_n-(n = 2, 4, 5, 8) and seven γ₂- to γ₈-forms. The β_n-forms consist of molecules tilted over the short subcell a_s-axis, whereas in γ_n-forms the molecular chains are tilted over the b_s-axis. All the modifications of alcohols and fatty acids studied have an orthorhombic subcell, while the neighbouring molecules in monomolecular layers are turned to each other at an angle of about 90°.