Einfluß der Struktur und der Morphologie von Bleicherden auf die Bleichwirkung bei Ölen und Fetten

Influence of the Structure and Morphology of Bleaching Earths on Their Bleaching Action on Oils and Fats In the manufacture of highly active bleaching earths from bentonite, the acid activation causes alterations in the chemical composition and structural as well as morphological properties of bentonite, depending on the concentration of acid, temperature, time etc. This has been demonstrated by changes in specific surface, volume of the micropores, particle size distribution and proportion of soluble silicic acid, and the impact of these alterations on the bleaching of vegetable oils is discussed. The results are supported by electron optical and X-ray investigations. Studies on repeated removal of silicic acid formed by acid treatment of bentonite as well as repeated acid activation indicate that the bleaching action of these earths depends not only on specific surface, but also, to a considerable extent, on the volume of micropores.     

Mischungen von Fetten und Ölen im internationalen Lebensmittelrecht und Einfluß der Harmonisierung in der EWG auf bundesdeutsches Recht

Blends of Fats and Oils in International Food Legislation and the Influence of EEC Harmonisation on German Federal Law Blends of fats and oils are of particular interest in terms of food legislation when milk fat is incorporated. In contrast to the existing standards of the Codex Alimentarius, the national legislation of each EEC member state contains far-reaching restrictions on this point which, however, are being or have been given up under the influence of the Cassis de Dijon judgement of the European Court of Justice. In 1988 France was the first EEC country to change its laws, the Federal Republic of Germany followed suit in 1990. At EEC level, the umbrella organisations of the dairy industry and the margarine industry have put forward suggestions for structuring the market for yellow fat spreads, which is to form a basis for EC legislation. In anticipation of EF legislation of this kind, Germany now permits, by virtue of an Order concerning margarine and mixed fat products of 31.8.1990, the production of mixed fat products consisting of fats fit for human consumption and a proportion of milk fat. The total fat content of these products must be 20–62% or at least 80%. The milk fat content must be between 15 and 25%, 45 and 55%, or 65 and 75% of the total fat content, but must account for at least 8% of the product weight.     

Veränderung der Sterine durch industrielle Verarbeitungsprozesse von Fetten und Ölen I: Einfluß der Raffinationsbedingungen auf den Steringehalt und die Sterinzusammensetzung

Alteration of Sterols by Industrial Processing of Fats and Oils I: Influence of Refining Conditions on the Sterol Content and Sterol Composition Action of bleaching earths on cholesterol was studied, both as solution in a neutral synthetic triglyceride and in hexan. The influence of reaction conditions on the amount and qualitative composition of the derivatives formed was investigated. The acidity of both the bleaching earth and the substrate are significant for the reaction. Furthermore, the type and amount of steryl esters as well as the concentration of bleaching earth and sterol in the fat play a role. By gas chromatography and thin-layer chromatography of the sterol derivatives formed it was found that the artefacts formed are qualitatively always the same although their proportions vary.     

Einfluß der Prozeßparameter auf die Tocopherolbilanz bei der Gewinnung von pflanzlichen Ölen

Effect of Process Parameters on the Balance of Tocopherols in the Production of Vegetable Oils. The influence of process parameters on the balance of tocopherols is investigated in five plants for the production of rapeseed oil with mechanical and extractive deoiling of the seed followed by physical or chemical refining. The state of the seed has an unexpectedly strong effect on the concentration of tocopherols in mechanically pressed oil. Warm pressing of the press cake results in twice as high concentration of tocopherols in the oil as cold pressing of the whole seed corn. With respect to the balance of tocopherols deodorizing is the most important refining step. Tocopherols are partly transferred into deodorizer condensates by distillation. Mathematical modelling of the continuous deodorizing shows the effect of temperature in good correspondence with measured results at a production plant. Enrichment of tocopherols from deodorizer condensates by means of high pressure extraction with supercritical carbon dioxide results in high concentration of more than 90% and high yield of about 70%.     

Die kontinuierliche Hydrierung von Ölen und Fetten

Continuous Hydrogenation of Oils and Fats The processes described till now for the continuous hydrogenation of glycerides are reviewed. The various systems are classified from the viewpoint of the reactor involved and their advantages and disadvantages are discussed. As an example of a modern plant for continuous hydrogenation, the reactor of BUSS AG, Basel, is described in details and its operational characteristics in the selective hydrogenation of fish oil are reported. The effect of pressure, temperature and catalyst concentration on the dilatation properties of the products at various temperatures and iodine values is given. Pressure was found to be the most important factor governing the selectivity. Finally, the consumption figures of a 150 to and a 250 to per day plant are presented.     

Der Futterwert von Fetten und Ölen aus Verarbeitungsprozessen bei Geflügel

Feeding Value of Fats and Oils from Finishing Processes for Poultry Altogether two trials with 22 different fats/oils have been carried out. In the first trial the interesterification and the digestibility of the fatty acids of seven fats and oils from the finishing processes with different contents of polymeres have been determined with broilers, aged 2–3 and 5–6 weeks as well as adult cocks. The age of the animals and the shares of the fatty acids were of high influence on the feeding value. In the second trial the fattening performance of broilers that had got ratios of 13 different frying oils, bleaching earth oils or distillation residues, was determined. The results with frying oils were successful, those with bleaching earth oils were moderate and with distillation residues extremely bad. A dependence between the content of polymeres and the feeding value of fat and oils could not be found out.     

Säulen-chromatographische Bewertung der Oxydationsstufe von Fetten und Ölen

Column Chromatographic Estimation of the Extent of Oxidation of Fats and Oils Oxidized fats and oils can be separated into oxidized and unoxidized fractions by column chromatography with aluminium oxide as adsorbent and benzene and ethanol-diethyl ether mixture as eluting solvents. The method is suitable for the evaluation of advanced oxidation where chemical methods can lead to false results.     

Einfluß der Glycerid-Verteilung auf die rheologischen Eigenschaften von Fetten

Effect of Glyceride Distribution on the Rheological Properties of Fats Investigations on suppository bases showed that the glyceride distribution influences the rheological properties of fats strongly. The authors presume that the viscosity behaviour is related to the random distribution of glycerides.     

Bestimmung von Schwermetallen in Ölen,Fetten und Futtermitteln

Determination of Heavy Metal Traces in Oils, Fats and Feeding-Stuffs Atomic absorption spectroscopy has proved to be the best method for the determination of lead, cadmium and mercury in fats, oils and feeding-stuffs, whereas colorimetry is best for the determination of arsenic. For each substrate the most suitable digestion method is described. Recoveries and detection limits of the determination methods are shown.     

Über die destillative Entsäuerung von Fetten und Ölen

Distillative Deacidification of Fats and Oils Based on the general principles of steam distillation, a method and diagrams for calculating the consumption of stripping steam in the distillative deacidification of various types of fats and oils are given. With the example of distillative deacidification of palm oil, it is shown as to how the minimum consumption of stripping steam is obtained in a two-step process. Subsequently, the corresponding determinations for palm kernel, coconut, peanut and rapeseed oils are shown. The operational scheme of a continuous plant for distillative deacidification and deodorization as well as photos of the fittings of the distilling cylinder are also included.     

Bestimmung von Tocopherolen in Ölen und Fetten: Einfluß des Tocopherol-Gehaltes von Erdnuß- und Sojaöl auf den Oxydationsverlauf dieser Öle beim Erhitzen I

Determination of Tocopherols in Oils and Fats: Influence of the Tocopherol Content of Ground-nut and Soybean Oils on the Course of Oxidation of these Oils on Heating I A sensitive method for the quantitative determination of α, γ and δ tocopherols in edible oils and fats was worked out. The tocopherols are isolated from unsaponifiable matter by thinlayer chromatography and ultimately each of them was determined photometrically from the red colour formed with iron chloride and bathophenanthroline. The effect of reduction in tocopherol content, resulting from the heating of oils, on the course of the oxidation of oil was followed, among others, with the help of 4-hexylresorcin. The blue dyestuff formed by this reaction was synthesized and identified as trimethin dye.     

Schnelle atomabsorptionsspektrometrische Bestimmungen von Spurenelementen in Ölen und Fetten

Fast Atomic Absorption Measurements of Trace Elements in Oils and Fats by Reduced Sample Preparation Atomic absorption measurements of trace elements in oils and fats can be performed either in aqueous solutions after wet digestion or directly inorganic solutions of the samples. But wet digestions are time-consuming and may cause contamination. Direct measurements are fast but are influenced in uncontrolled manner by the matrix or the state of the trace elements in the sample. Such possible errors can be widely reduced if the samples are treated with concentrated formic acid before being measured directly in an organic solution. With formic acid the organic standards can also be prepared from aqueous solutions.     

Erfahrungen bei der Hydrierung von einigen Ölen und Fetten mit einem Kupferkatalysator

Experiences on the Hydrogenation of Fats with a Copper Catalyst Soybean oil, rapeseed oil and lard were hydrogenated using a copper catalyst. The products of hydrogenation were refined after the removal of copper following a new technique. The aforesaid oils were also hydrogenated with a nickel catalyst to the same iodine value and then refined. The products of hydrogenation using copper showed a better stability towards oxidation than those obtained with nickel.     

Der Einfluß der EWG-Gesetzgebung und -Rechtsprechung auf Verwendung und Einsatz von Fetten aus lebensmittelrechtlicher Sicht

The Influence of EEC Legislation and Court Decisions on the Use of Fats under Food Law EEC product legislation to date takes hardly any account of the significance of fat as an important food. In the field of horizontal legislation, the labelling Directive regulates the use of oil and fat as category names in the list of ingredients. The Directive on dietetic foods stipulates that the total fat content of a dietetic food must be stated in the list of nutrients. For other foods a standardisation of voluntary statements of food values is being prepared. The ?Cassis”? judgement of the European Court of Justice was and still is of considerable influence. As the result of a judgement passed on Belgian law, the German legislature has repealed the regulations concerning the shape of margarine packs and has now, finally, given clearance to the ?butter shape''. The raising of the prohibition of milk substitute products for import trade will also have consequences for German producers, at least in some sectors. The EC umbrella organisations of the dairy and margarine industries propose structuring the market for yellow spreading fats at EEC level. Consideration is also being given to the use of vegetable fat in the manufacture of ice cream. The prohibition relating to the addition of extraneous fat to chocolate could become the subject of further proceedings before the European Court of Justice. In the case of other food products, e. g. bakery goods, sauce hollandaise and sausage, the effects of incorporating vegetable fat on the product name is the subject of disputes before national courts, during which the influence of European law is becoming ever stronger.     

Schnellmethode zur Isolierung der Sterine aus Fetten und Ölen

Rapid Method for Isolation of Sterols from Fats and Oils Isolation of sterols from fats and oils mostly takes place by the very time-consuming solvent extraction of the unsaponifiable from the soap solution. The time required can be reduced to about 1 hour by a new developed procedure which makes possible to separate soaps and polar components of the fats from the saponified sample by aluminium oxide columns. The use of 250 mg of fat is sufficient for a following sterol examination by gas chromatography.     

Separation von Feststoffen aus Fetten und Ölen durch Elektrophorese

Separation of Solids from Fats and Oils by Electrophoresis The development of PETRECOR ELECTROFILTER^TM SEPARATOR provides the food industry with plants that enable the separation of solid particles, including those in the submicron region (< 0.5 μm), from fats and oils with the aid of high-voltage electrical field. The most important commercial application is the removal of bleaching earth and nickel catalyst; a final polishing filtration becomes unnecessary. Results of pilot plant operation show, for example in the removal of nickel catalyst from hydrogenated soybean oil, a continuous reduction of nickel from 500 ppm to < 0.15 ppm. These plants are completely closed systems under slight pressure with a definite precalculated capacity for solids; the latter can be removed by a simple regeneration process involving rinsing with the product to be treated. This regenerating liquid is a pumpable suspension containing ca. 5% solids; it is subjected to further treatment. Plants of various sizes with respect to maximum flow rate and capacity are available. The layout is always done for the specific application.