Analytische Methoden zur Beurteilung der Frische und Haltbarkeit tierischer Fette

Analytical Methods for the Assay of Freshness and Stability of Animal Fats It is evident from the theory of autoxidation that the characteristic values alone are not suitable criteria for the assessment of freshness of animal fats. Organoleptic evaluation of taste and flavor are absolutely essential. Since the stability of fats is proportional to the induction period during autoxidation, measurement of the latter provides the basis for evaluation of storage stability of animal fats. Determination of characteristic values or measurement of the rate of oxidation are not suitable for this purpose, since they do not account for the action of prooxidants and antioxidants. Automatic version of SWIFT-test as described by the author earlier (FSA 74 , 366 [1972]) enables the determination of induction period with little effort.     

Fortschritte in der Gewinnung und Verarbeitung von Pflanzenlecithinen

Progress in Production and Processing of Vegetable Lecithines Production and processing of vegetable lecithines, won as secondary products of edible oil production, have only very seldom been the subject of publications in German literature during the last decades. Since 1950 remarkable improvements have been achieved in this field. In detail they concern the hydratation methods, the fractionation procedures which are worked out to separate neutral lipids, unwelcome phosphatides and oligosaccharides as well chemical and enzymatical reactions by which the emulsifiability and the dispersing power of the lecithine preparations can be improved. The present report bases on scientific publications and patent literature. It considers beyond that the results obtained in the author's laboratory.     

Die Entsäuerung von Pflanzenölen mit Ammoniak Eine umweltfreundliche Raffinationsmethode

Deacidification of Vegetable Oils with Ammonia – An Environmentally Safe Refining Method Compared to conventional deacidification of vegetable oils using sodium hydroxide, neutralization with aqueous ammonia has the advantage of being safe to environment, because the deacidification agent can be repeatedly reused. Oils, especially soybean oil with low degree of oxidation, can be fully deacidified only with the help of ammonia. A post-refining with 0.5 N sodium hydroxide at 95-100° C reduces the residual phosphorus content to 1-4 ppm. The same effect can be frequently achieved by a preliminary desliming with 5% formic acid or citric acid. Deodorization at 210° C of oils that have been deacidified with ammonia and washed with water yields bland and pale edible oils having good keepability.     

50 Jahre Technologie pflanzlicher Öle und Fette - ein Erfahrungsbericht

50 Years Technology of Vegetable Oils and Fats - a Report of Experiences In a survey about the development of the technology of vegetable oils and fats between 1932 and 1982 above all those areas are dealt, in which the author could contribute to the optimization of technological process steps and to the quality improvement of final products. It is described in detail: influence of solvent composition on benzine losts and on hydrocarbon retention in the oil seed extraction, improvement of the lecithin removal process, the entire desliming of extracted oils and its influence on raffinate quality, methods for determination of refining lost and for estimation of quality of raw and refined oils, comparison between various alkali-neutralization methods, relations between bleaching earth activity and oxidation stability of the oils, recovery of oil from used bleaching earth, distillative neutralization and determination of optimal deodorising conditions. The report is finished with hints on the importance of special fats for the fat processing industry obtained by hydrogenation, interesterification or fractionation.     

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Tools in metabonomics: an integrated validation approach for LC-MS metabolic profiling of mercapturic acids in human urine

While for 1H NMR techniques there already exist common analytical and reporting standards, this does not apply to LC-MS metabolic profiling approaches. These standards are the more recommended when applying metabonomics to human biofluids, particularly urine samples, due to the high degree of biological variation compared to animals. A control study was performed, and urine samples of 30 healthy male and female human subjects were collected at intervals of 8 h twice a day for three consecutive days. Using selective multiple reaction monitoring in combination with a column-switching tool for the analysis of the mercapturate pattern, samples were screened for time and gender differences, the most common confounders. Data preprocessing parameters, alignment, scaling to internal standards, and normalization techniques were optimized by PCA, PLS-DA, and OPLS models. Great care was taken in the validation process of both analytical and chemometric protocols. Additionally, a problem of LC-MS, the combination of "different-batch" data to "one-batch" data could be solved by a batchwise scaling procedure. Based on these results, the use of metabolic profiling via mercapturates will be feasible for the detection of disease or toxicity markers in the future since mercapturates are important biomarkers of reactive metabolites known to be involved in many toxic processes.     

Survival and growth of epidemically successful and nonsuccessful Salmonella enterica clones after freezing and dehydration

The spread of epidemically successful nontyphoidal Salmonella clones has been suggested as the most important cause of salmonellosis in industrialized countries. Factors leading to the emergence of success clones are largely unknown, but their ability to survive and grow after physical stress may contribute. During epidemiological studies, a mathematical model was developed that allowed estimation of a factor (q) accounting for the relative ability of Salmonella serovars with different antimicrobial resistances to survive in the food chain and cause human disease. Based on this q-factor, 26 Salmonella isolates were characterized as successful or nonsuccessful. We studied the survival and growth of stationary- and exponential-phase cells of these isolates after freezing for up to 336 days in minced meat. We also investigated survival and growth after dehydration at 10°C and 82% relative humidity (RH) and 25°C and 49% RH for 112 days. Stationary-phase cells were reduced by less than 1 log unit during 1 year of freezing, and growth was initiated with an average lag phase of 1.7 h. Survival was lower in exponentialphase cells, but lag phases tended to be shorter. High humidity and low temperature were less harmful to Salmonella than were low humidity and high temperature. Tolerance to adverse conditions was highest for Salmonella Infantis and one Salmonella Typhimurium U292 isolate and lowest for Salmonella Derby and one Salmonella Typhimurium DT170 isolate. Dehydration, in contrast to freezing, was differently tolerated by the Salmonella strains in this study, but tolerance to freezing and dehydration does not appear to contribute to the emergence of successful Salmonella clones.