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Ham yağlar istenmeyen maddelerin uzaklaştırılması için tüketimden önce rafine edilir ve deodorizasyon genellikle rafinasyonun son aşaması olarak kullanılır. Laboratuvar tipi cam deodorizatörde, yapışkan maddelerinden uzaklaştırılmış, asitliği alınmış ve ağartılmış Sclerocarya birrea (SCO), darı böceği (SBO), su ile ekstrakte edilmiş kavun böceği (MBOH2O) ve solvent ile ekstrakte edilmiş kavun böceği yağları (MBOSOL) farklı sürelerde (0.5; 1 ve 2 saat) ve farklı sıcaklıklarda (190, 210, ve 250 °C) deodorize edilmiştir. Kalite değişimleri (serbest asitlik, peroksit değeri, tokoferoller, steroller ve fosfatidler ) belirlenmiş, yağ asitleri dağılımının yanında, ransimat ile oksidatif stabilite tespit edilmiştir. Deodorizasyon sıcaklığı ve süresi fosfatidleri etkilemezken, peroksit ve serbest asitler bütün örneklerde deodorizasyon sıcaklığı arttıkça önemli düzeyde azalmış (P

The behavior of crude Sclerocarya birrea kernel oil (SCO) and Sorghum bug (Agonoscelis pubescens) oil (SBO) during deep-frying of par-fried potatoes was studied with regard to chemical, physical, and sensory parameters, such as content of FFA, tocopherols, polar compounds, oligomer TG, volatile compounds, oxidative stability, and total oxidation (TOTOX) value. Palm olein was used for comparison. Whereas potatoes fried in SCO that had been used for 24 h of deep-frying at 175°C were still suitable for human consumption, potatoes prepared in SBO that had been used for 6 to 12 h were not, considering the sensory evaluation. In looking at the chemical and physical parameters, SBO exceeded the limits, after no later than 18 h of use, for the amount of polar compounds, oligomer TG, and FFA recommended by the German Society of Fat Sciences (DGF) as criteria for the rejection of used frying oils. In contrast to SBO, SCO oil did not exceed the limits for the content of polar compounds and oligomer TG during the frying experiment. Only the amount of FFA was exceeded; this was because the amount of FFA at the beginning of the experiment was higher than for refined oils. The results showed that both oils were suitable for deep-frying of potatoes, but remarkable differences in the time during which both oils produced palatable products were found.

Improvement of the oxidative stability of sunflower kernel oil (SKO) by blending with highly stable unconventional edible Sudanese oils was investigated. Blends (9 : 1, 8 : 2, 7 : 3, 6 : 4, w/w) of sunflower oil with Sclerocarya (Sclerocarya birrea) oil (SCO) and melon bug (Aspongopus viduatus) oil (MBO), respectively, were studied with respect to the fatty acid composition, the oxidative stability (Rancimat 120C) and stability at 70C using peroxide value. By increasing the proportion of SCO and MBO in SKO, the linoleic acid content decreased from 46.3 to 31.2% (SCO) and 30.1% (MBO), respectively, while the oleic acid content increased from 41.3 to 51.0% (SCO) and 43.9% (MBO), respectively. As a result of blending SKO with SCO and MBO, respectively, the oxidative stability in the Rancimat test was improved from 47 to 147% in (SCO) and from 5 to 68% (MBO) compared to the SKO as control, with increasing parts of SCO and MBO, respectively. Storage of the blends at 70C showed that the increase of the peroxide value as a measure of oxidation was remarkably lower for the mixtures of MBO and SCO with SKO than for pure SKO. This study demonstrated a means for improving the stability of sunflower oil by blending with SCO and MBO.

Three unusual oils, obtained from Sclerocarya birrea (Marula), Aspongopus viduatus (melon bug) and Agonoscelis pubescens (sorghum bug), collected in Sudan from Abu Gibaiha, Ghibaish and Rahad agricultural areas, respectively, were investigated. In addition to the oil content, the fatty acid as well as sterol composition was determined by capillary gas chromatography and the tocopherols were evaluated by high-performance liquid chromatography. Oxidative stability of the oils was investigated by the Rancimat method. The oil content of seeds from S. birrea amounted to 53.5%, whereas bugs of A. viduatus and A. pubescens came to 45 and 60%, respectively. The oils contained 67.2, 46.5 and 40.9% oleic acid, 5.9, 3.4 and 34.5% linoleic acid, 14.1, 44.2 and 12.1% palmitic acid and traces of linolenic acid, respectively. The tocopherol content of these oils amounted to 13.7, 0.3 and 34.0 mg/100 g oil, respectively. Gamma-tocopherol was the predominant tocopherol in the oil of S. birrea and A. pubescens. The total content of sterols in the three oils was 287, 17 and 450 mg/100 g oil, respectively, whereas β-sitosterol was determined as the main compound in all oils with about 60% of the total sterols. In the oil of S. birrea higher amounts of 5-avenasterol (4.8 mg/100 g) were found. The oxidative stability of the oils, as measured by the Rancimat test at 120C, was 43, 38 and 5.1 h, respectively.

During the processing of meat mutagenic imidazoquinolines and -quinoxalines (“IQ compounds”) may be formed by the Maillard reaction of reducing sugars, amino acids, and creatine/creatinine. For analytical determination, the IQ compounds were extracted with methanol, fractionated, separated by reversed phase HPLC and identified by gas chromatography/mass spectrometry. Although IQ compounds are already formed at moderate temperatures, increasing temperature causes a large increase in the rate of formation; a decrease of water activity further promotes the formation of IQ compounds.

Only by the use of scanning electron microscope in investigations concerning the metal-porcelain interface of ceramic masses upon metal frames (approx. 160 crowns since 1967), essential differences in the reason of mistakes have been revealed recently. Primarily, methodic mistakes are to be declared relevant. Independent of their veneering origin, they contribute to fractures within the ceramic layer or to crack-offs of the fired ceramic masses from the metal frame. Obviously, the systemic causes for mistakes in metal ceramics revealed to be dependent on the groups of veneers. Veneering involves non-manageable reasons for mistakes. These qualities in the material are the coefficient of thermal expansion or the share of palladium in the veneer. Very often, palladium is responsible for the formation of bubbles in the ceramic layer, and thus it is the reason for the development of cracks. The so-called pure titanium is quite extraordinary, when covered with ceramic mass, because the so-called alpha case layer cannot be bridged, despite 10 years of permanent research in that field. The clinical critical examination of systemic mistakes, however, proves to be mild. Clinical reasons for mistakes in metal ceramics remain disregarded in this paper.

In the view of the patients, Galvano-Inlays fulfil esthetic requirements in contrast to cast restaurations. However, it was decided to evaluate the fine gold margins. The marginal seal of Galvano-Inlays in different stages of production was evaluated by means of light microscopy, and scanning electron microscopy. In addition Galvano-Inlays which had been in the mouth for two years, were evaluated in the same way. Besides good contact of the fine gold to the tooth, marginal discrepancies in the range of 60 to 160 microns were found which can hardly be improved by means of burnishing. After all, the insufficiency results from the inevitable gap of cementation or from breaking failure of the polished and thus hardened margin of the fine gold.

The influences of processing conditions and composition on chemical changes during thermal processing of tomatoes were investigated. During the Cold and Hot Break process pectin is degraded to different extents. Due to the thermal impact at first cyclization of glutamine to pyroglutamic acid takes place. At higher dry weight contents and during drying processes Amadori compounds and browning can be detected. The reaction products formed during thermal processing can be analysed by amino acid analysis and-after proper derivatization-by capillary gas chromatography.

Radiation-induced oxidation of fatty foods was detected by a chemiluminescence method. Hazelnuts, peanuts and poultry were used as foodstuff samples. Additional investigations were performed with a model system and sunflower oil. The irradiation of the samples was carried out in a x-ray-fluorescence-apparatus. Thereby it is to note that the G-value of the x-ray-radiation is much higher than the G-value of a cobalt-60-source normally used for irradiation of food. A dependence of the integral of the light curve on the irradiation doses could be proved. Investigations with model systems which contained different amounts of alpha-tocopherol showed a decreasing chemiluminescence signal at low irradiation doses in presence of alpha-tocopherol. At higher doses the chemiluminescence signal enlarges with increasing amounts of alpha-tocopherol because irradiation products of alpha-tocopherol overlay its antioxidative effect. Irradiated poultry samples differ significantly from unirradiated samples after a deep-freeze storage of 26 weeks. A quantification of the doses is not possible without knowledge of the storage time, because the integrals decrease differently after irradiation during storage. In any case the chemiluminescence method is useful as a "screening method" for the detection of irradiation of foodstuffs with the possibility of automation and high sensitivity.

Examining 230 edentulous patients, a significant degree of atrophy in the maxilla and mandible relatively often has been found. Atrophy could be detected more often in the mandible of female patients. For these forms of manifestation, among others, systemic causes: osteoporosis, diabetes and periodontal disease could be found. The results and their classification may help to draw the attention in the course of treatment to strong dissimilarities or similarities of the edentulous mouth. The degree of atrophy observed on both jaw-bones--among other factors--is significant for the planning and prognosis when indicating total prosthetic treatment.

During meat processing mutagenic imidazoquinolines and imidazoquinoxalines ("IQ-compounds") may be formed by Maillard reaction of reducing sugars, amino acids, and creatine/creatinine. IQ-compounds isolated from low-moisture model systems and meat extract by liquid-liquid-distribution were fractionated on a cation exchanger and separated on an RP phase. After acetylation the separated compounds were identified by gas chromatography/mass spectrometry based on their characteristic mass fragment ions. During heating the model systems at 100 degrees C the formation of IQ-compounds begins and greatly increases by further raising the temperature. In different amounts IQ-compounds could also be detected in commercially available meat extracts.

Out of the great number of very important investigations on metal ceramics, only a small section can be represented. Those precious metal alloys which were developed for metal ceramics 25 years ago, were able to create and body confidence in the new ceramic proceedings of production for crowns and bridges. The number of failure caused by cracking and bursting was of a minor kind. The necessity of having cheaper alloys at one's disposal, e.g. gold-reduced alloys, palladium-alloys and non-precious metal alloys, involved that investigations for locating mistakes in the ceramics were carried through. Afterwards, changes of working methods had to be tested, in order to eliminate bubbles and cracks. The demonstrated results are designed to achieve better crowns and bridges. Allbountiful instructions are not possible, however, each alloy and each ceramic mass requires a special method of handling. If this happens, metal ceramics should continue to be a valuable clinically practicable method.

The groups A1 to C3 of the "group classification of partially edentulous arches" by Eichner are characterized by the number of teeth and the topography of the natural dentition. This could be demonstrated in a clinical study on 1000 patients prepared by Blume-Gréger. The result shows a percentage of 49.5 in the groups A, 22.4% in the B-groups and 28.1% in the C-groups. Furthermore, these groups represent the course of tooth loss also regarding the functional value of the natural dentition. Thus, this classification provides a standard for the degree of morbidity of the dentition and is suitable for application in studies on morbidity statistics. When used for documentation files there is an error possibility of 1.9%.

Amadori-Verbindungen werden im Gegensatz zur Braunung ohne Induktionsperiode und bevor sensorische Veranderungen auftreten, gebildet, sie konnen daher fur die Fruherkennung durch Maillard-Reaktionen hervorgerufener Qualitatsveranderungen herangezogen werden. Die Geschwindigkeiten, mit der Amadori-Verbindungen gebildet werden, hangen von den Herstellungs- und/oder Lagerungsbedingungen ab; Amadori-Verbindungen nehmen — ebenso wie die Geschwindigkeiten ihres Abbaus — mit steigendem Wassergehalt und ansteigender Temperatur zu. Die Temperaturkoeffizienten (Q10-Werte) der Bildung dieser Braunungszwischenstufen sind hoher als diejenigen der Braunung.

Die drei Monohydroxypyridine werden von Peroxydase und Wasserstoffperoxid nicht oxydiert. Von den sechs isomeren Dihydroxypyridinen wurde nur das 4-Hydroxy-pyridon-(2) nicht angegriffen, wahrend das 5- und das 6-Hydropyridon-(2) besonders leicht oxydierbar sind, wobei intermediar intensiv gefarbte Verbindungen entstehen. Zwei Zwischenprodukte der Oxydation des 5-Hydroxypyridons-(2) wurden isoliert und als 2,2′,5,5′-Tetrahydroxy-dipyridyl-(6,6′) und 2,2′,5,5′-Tetrahydroxy-3,3′-diaza-diphenochinon-(4,4′) oder seine tautomeren Formen identifiziert. Oxidation of Hydroxy Pyridines, specially 2,5-Dihydroxypyridine The three monohydroxypyridines are not oxidized by peroxidase and hydrogen peroxide. Further, the six isomeric dihydroxypyridines were investigated: 4-hydroxy-pyridone-(2) is not attacked by peroxidase; on the other hand 5-hydroxy-pyridone-(2) and 6-hydroxypyridone-(2) are very easily oxidized forming intensively coloured intermediary compounds. From the oxidation of 5-hydroxy-pyridone-(2), two intermediates were isolated and identified as 2,2′,5,5′-tetrahydroxy-dipyridyl-(6,6′) and 2,2′,5,5′-tetrahydroxy-3,3′-diaza-diphenoquinone-(4,4′) or its tautomeric forms.

Solubility tests of eight dental cements showed that the rate of solubility can be fitted to a mathematical expression that indicates that solubility decreases exponentially in time. Solubility was increased by continually presenting fresh liquid, unsaturated with solute, to the cement-water interface. A liquid absorption test was developed to give an additional criterion for the life of dental cements.

Die Packstoffauswahl fur sauerstoff-empfindliche Lebensmittel erfolgt bisher fast ausschlieslich empirisch. Um dieses aufwendige und gleichzeitig unsichere Verfahren zu rationalisieren, liegt es nahe, eine geeignete Berechnungsmethode zu entwickeln. Hierzu war es notwendig, die Sauerstoff-Toleranzen und die Haltbarkeitszeiten sowie die Sauerstoff-Verbrauchskurve in Abhangigkeit vom Sauerstoff-Partialdruck von zu verpackenden Lebensmitteln zu bestimmen, denn diese experimentellen Daten sind die Voraussetzung fur eine Berechnungsmethode, mit der das Lagerverhalten eines verpackten, sauerstoff-empfindlichen Lebensmittels simuliert, die Haltbarkeitszeit vorausberechnet und die Packstoffgrosen dimensioniert werden konnen. Es wurde eine Apparatur zur Messung des Sauerstoff-Verbrauchs von Lebensmitteln entwickelt. Damit wurden dann die Sauerstoff-Toleranzen und die Haltbarkeitszeiten von drei Lebensmitteln bestimmt. Es ergab sich, das die Sauerstoff-Toleranzen nicht konstant sind, sondern vom Sauerstoff-Partialdruck und der Zeit abhangen. Mit einem iterativen Computerprogramm konnten die Forderungen nach gezielter Packstoffauswahl und Vorausberechnung der Haltbarkeit eines verpackten, sauerstoffempfindlichen Lebensmittels erfullt werden. Die Richtigkeit der Berechnungsmethode wurde durch Lagerversuche in sauerstoff-durchlassigen Behaltern bestatigt.