Wechselwirkungen zwischen Aromastoffen und Lipiden 1. Mitteilung: Sorption einiger leichtflüchtiger Stoffe an reine Lipide

Interactions Between Aroma Substances and Lipids 1. Sorption of Some Volatile Substances in Pure Lipids Ethyl acetate, n-hexane, ethanol, and acetone are sorbed much better by liquid lipids than by solid ones. The sorption capacity of liquid lipids increases in the order triglyceride, free fatty acid, fatty acid methyl ester, and also with decreasing chain length of the fatty acid residues. Oleic acid derivatives sorb more than stearic acid ones. The sorbed amounts decrease in the order ethyl acetate, ethanol or hexane, acetone. This holds for the sorption of small amounts (some mmol/kg) measured by the retention volumes in gas chromatography, and for the sorption of greater amounts, which was measured by gravimetry. The sorption is a physical one. The sorption heats are 25–35 KJ/mol. Stronger binding is observed between phenol and esters and between n-butylamine or pyridine and free acids.     

Die Lipide der Stärken — ein Forschungsgebiet zwischen Kohlenhydraten und Lipiden

The Lipids of Starch — Research between Carbohydrates and Lipids The lipids of cereals are distinguished by a variety of polar lipids which have importance for the technological properties of cereal products. In this context the lipids of starch have a special role. They are present in the form of inclusion compounds of the amylose and they distinguish themselves from the usual lipids by the lysophosphatides which are rarely found in nature. The main compound, the lysolecithin, a lipid of strong hemolytic effect, is only to be found in form of the 1-acylisomer. Between amylose and lipids interaction exists; lipids as partners have to fullfil some conditions in constitution. Lipids as far as they are qualified for inclusion have already in low concentration a distinct influence on the viscosity of starch pastes and with it on the rheological properties of starch gels.     

Untersuchungen über die Zusammenhänge zwischen thermodynamischer Stabilität der Kakaobutter und der Lagerbeständigkeit der Schokolade

Investigations on the Relationship between the Thermodynamic Stability of Cocoabutter and Storage Stability of Chocolate In a previous work

1 H. Witzel u. K. Becker, Über die Kristallstruktur der Kakaobutter, Fette · Seifen · Anstrichmittel 71 , 507 [1969].

, the crystalline structures and molecular arrangements of unstable pre-β-form and stable β-form of cocoabutter could be elucidated. In the present work, attempts were made to determine quantitatively the amounts of pre-β-form and β-form of cocoabutter in chocolate by x-ray technique. Furthermore, the influence of the amount of unstable pre-β-form on the rate of formation of fat bloom was investigated. It was found that the quantitative determination of pre-β- and β-forms is not possible. However, from the intensity of some x-ray reflexes conclusions regarding the resistance of chocolate towards the formation of fat bloom can be drawn.     

Beiträge zur Schaumreinigung fester Oberflächen 2. Mitteilung: Schaumeigenschaften und Wirksamkeit

Foam Cleaning of Solid Surfaces 2. Foam Properties and Effectiveness Cleaning foams are very stable. Although the foam gives up almost the entire amount of liquid entrained in the lamella within 20 min, the original volume is retained. The highly alkaline solution released wets the soiled surface of the tile, swells the dried up protein rest and dissolves the same, which is subsequently removed by rinsing with water. The effectiveness of foam cleaning can be increased by up to 10% using longer periods of action of the foam on the soiled surface. Mechanical and heat treatment are of limited value in foam cleaning.     

Strukturaufklärung von ausgewählten nitro- und sulfonsäuresubstituierten 1,2-Naphthochinon-2-diaziden

Structure Determination of Selected Nitro and Sulfonic Acid Substituted 1,2-Naphthoquinone-2-diazides Selected nitro derivatives of 1,2-naphtoquinone-2-diazide 2 and 5 have been synthesized, the position of the NO₂-group has been unambigously determined by means of ¹H and ¹³C n.m.r. spectroscopy, and the structure of these compounds has been comprehensively determined in relation to unsubstituted 1 and sulfonic acid substituted derivatives 3 , 3a , 4 and 4a . Furthermore, the spectroscopical behaviour, especially in the uv/vis region, was examined in correlation to quantum chemical calculations.     

Simulation der auf van der Waals Wechselwirkungen beruhenden Haftkräfte zwischen rauen Partikeln und glatten Wänden in gasförmiger Umgebung

A computer program is presented that can be used to calculate adhesion force distributions of irregularly shaped particles. Basis is the calculation of the single interactions between the involved atoms respectively molecules of the contact partners and overlapping these to a resultant whole interaction. The example of roughness shows that extremely bimodal distributions can arise for identical particles.     

Untersuchungen über die Wechselwirkungen zwischen Proteinen und verschiedenen Schmelzmitteln der Schmelzkäse-Herstellung Viskositäts-Messungen mit dem Ubbelohde-Viskosimeter an Mischungen von Lösungen des αs-Caseins und von Phosphat-Oligomeren

Investigations on the Interaction between Proteins and Various Melting Agents Used in Manufacture of Molten Cheese: Viscosity Measurements on Mixtures Containing Solutions of α_s-Casein and Phosphate-Oligomers Using Ubbelohde-Viscometer Specific viscosities η_sp of mixtures containing solutions of α_s-casein and phosphate-oligomers (pyro-, tripoly-, trimeta- and tetrametaphosphate) were determined by Ubbelohde-viscometer at 20°C. Pyro- and tripolyphosphate show strong interaction with α_s-casein; the specific viscosities of these components were not additive. Also in mixtures containing solutions of α_s-casein and cyclic tetrametaphosphate, interaction to a small extent is detected. As against this, trimetaphosphate which is also a cyclic oligomer, hardly interacts with α_s-casein. Amongst the aforesaid phosphates, only trimetaphosphate does not yield homogeneous molten cheese. Determination of reduced viscosities η_sp/c led to same results.     

Über die Autoxydation von Linolsäure-methylester in Wasser, 2. Mitteilung: Isolierung und Identifizierung von 4-Hydroperoxy-nonen-2,3-al-1 und 8-Hydroperoxy-caprylsäure-methylester

About the Autoxidation of the Linoleic Acid Methyl Ester in Water II. Isolation and Identification of 4-Hydroperoxy-nonen-2, 3-al-1 and 8-Hydroperoxycaprylic Acid Methyl Ester From the water soluble complex reaction products, formed in the ‘water reaction’ of 9,12-linoleic acid methyl ester, two new, till now unknown, lipidhydroperoxides are chromatographically isolated and analysed with chemical and physical methods. The results show that they are hydroperoxycaprylic acid methyl ester and hydroperoxy-2,3-trans-nonenal-(1). For the ultimate analysis data, both the hydroperoxides were first reduced with SnCl₂ to the corresponding hydroxy compounds. The reduction product of the first hydroperoxide was found to be 4,4′-nitroazobenzoic acid ester and that of second as 2,4-dinitrophenylhydrazon.     

Elektrochemisches Verhalten von N-Aryl-Δ2-pyrazolinen. VIII. Zusammenhänge zwischen dem anodischen und kathodischen Verhalten und den Absorptions- und Fluoreszenz-eigenschaften von N-Aryl-Δ2-pyrazolinen

Electrochemical Behavior of N-Aryl-Δ²-pyrazolines. VIII. Relationships between the Anodic and Cathodic Behaviour and the Absorption and Fluorescence Properties of N-Aryl-Δ²-pyrazolines The anodic and cathodic half-wave potentials in acetonitrile and dimethylformamide (DMF) and the absorption and fluorescence spectra in DMF and cyclohexane of 61 N-aryl-Δ²-pyrazolines have been measured. The following correlation has been found between the difference of the half-wave potentials E–E of the first oxidation and reduction steps and the fluorescence maximum in DMF, h · ν: This confirms the charge-transfer character of the corresponding spectroscopical transition. The deviations of some compounds from this correlation are due to differences in the electrochemical behaviour as, e.g., the cathodic elimination of halogen from halogen substituted pyrazolines or the intramolecular hydrogen bond in 1, 5-diaryl-3-o-hydroxyphenyl-Δ²-pyrazolines.     

Untersuchungen an Fritierfetten; Zusammenhänge zwischen dem Gehalt an petroläther-unlöslichen oxidierten Fettsäuren und dem Gehalt an polaren Substanzen bzw. dem Gehalt an polymeren Triglyceriden

Investigation of Deep-Frying-Fats; Correlations Between the Content of Petroleum Ether-Insoluble Oxidised Fatty Acids and the Content of Polar Substances or the Content of Polymeric Triglycerides Respectively In 1973, the Deutsche Gesellschaft für Fettwissenschaft issued a recommendation of the assessment of used deep-frying fats in which special importance has been attached to the content of petroleum ether-insoluble oxidised fatty acids. However, the determination is time-consuming. Moreover, according to definition, only small amounts of the total oxidised fatty acids are determined. The results of other, less time-consuming methods of investigation which, in addition, may be carried out directly in the deep-frying fat without necessitating chemical attacks have been compared with those of the method ?petroleum ether-insoluble oxidised fatty acids”?. Samples of 4 types of fat which had been used for deep-frying in snack bars under different conditions were investigated by the following procedures:

• 1 Determination of the petroleum ether-insoluble oxidised fatty acids (ox FA)
• 2 Column chromatographic determination (CC) of the polar components
• 3 Liquid chromatographic determination (LC) of the sum of those substances which are more polar than unchanged triglycerides
• 4 Gel permeation chromatographic determination (GPC) of the polymeric triglycerides.

It was found that there are statistical relations between 1. and 2. resp. 3. resp. 4. The mean value of the distributions are laying approximately on parabolas. Thus, it is possible to replace the limit values for the content of petroleum ether-insoluble oxidised fatty acids of 0.7 or 1.0% recommended by DGF by corresponding values of the other methods.     

Kunststoffe in der Milchwirtschaft — eine kritische Studie,V. Mitteilung: Zur Reinigung und Desinfektion von Kunststoffoberflächen 2. Teil: Hygienische Beschaffenheit von Kunststoffoberflächen und ihre Folgen

Plastics in the Milk Industry — A Critical Study, V. Communication: Cleansing and Disinfection of Plastic Surfaces 2nd Part: Hygienic State of Plastic Surfaces and Their Consequences Plastic articles, meant for repeated use in direct contact with food-stuffs can permanently establish themselves, only if success is achieved in maintaining plastic appliances and parts clean and germ-free without much difficulty. Because in some respects the properties of the plastics deviate from those of hitherto employed materials of construction, the former set specific requirements on cleansing agents and cleansing processes. The cleansing solutions for the plastics must be physico-chemically more effective, in order to overcome the strong adhesion of fatty impurities. Since it is basically doubtful, whether polyolefines without adverse effects can at all be employed for repeated use in direct contact with fat-containing milk products, intensive trials should be made with plastics having lower affinity for fat.