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Emilia Janiszewska Dorota Witrowa‐Rajchert 《International Journal of Food Science & Technology》2009,44(12):2438-2444
The influence of particle morphology of spray dried powders obtained by using different carriers on the efficiency of microencapsulation of rosemary aroma is shown in the present research. It was found that the type of the carrier influenced the size but not the shape of rosemary aroma capsules and all the capsules were spherical with cracks. The biggest particles, d50 = 55 μm, were obtained with 25% maltodextrin (MD) as a carrier, and the smallest, d50 = 29 μm with 30% gum arabic (GA). The efficiency of encapsulating aroma inside of the capsules depended on the particles size and apparent density. An increase in the quantity of microencapsulated aroma from 10% for 25% MD to about 60% for 30% GA as the carrier was seen, which co‐related with a decrease in the average diameter of the powder particles. Similarly, an increase in the efficiency of aroma retention was followed by an increase of apparent density of powders from 796 (25% MD) to 1156 kg m?3 (30% GA). 相似文献
64.
Rare earth complexes with trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (DCTA) of the Ln(dcta)- ype exhibited an unusual sequence of affinity on the polystyrene anion exchangers: pm3 >Nd3 >Sm3 >pr3 >Ce3 >Eu3 >Gd3 >La3 >Sc3 >Tb3 >Dy3 >Ho3 >y3 >Er3 >Tm3 >yb3 >Lu3 [1]. Taking into account the position of Y3 , Sm3 , and Nd3 in this affinity series, for the monodispersive polystyrene anion exchangers, Lewafit MonoPlus M 500, Lewatit MonoPlus M 600, Lewatit MonoPlus MP 500, Lewatit MonoPlus MP 64,and for the heterodispersive anion exchanger, Lewatit MP 62, the weight (Dg,) and bed (Dv) distribution coefficients of these complexes and working ion exchange capacities (Cw) were determined. Based on these values, purifications of Y3 from Nd3 and y3 from Sm3 in the macro-micro component system on these anion exchangers were studied. The application potential of this method was highlighted for the separation of yz3 in the presence of Nd3 and Sm3 . With 1 L of monodispersive and strongly basic polystyrene gel anion exchanger Lewatit MonoPlus M 500 in the acetate form, it is possible to obtain approximately 79 g Y2O3 purified from Nd2O3 and 70 g Y2O3 purified from Sm2O3 in the same process condition. 相似文献
65.
Flammability, smoke evolution, thermal, and thermomechanical properties of low-density rigid polyurethane foams obtained from different aromatic polyols were investigated. The foams were prepared according to a standard formulation ensuring the same foam phosphorus content. Cellular polyurethanes with the best fire resistance were obtained from polyols containing disubstituted naphthalene and biphenyl rings. A linear equation was proposed to describe the influence of various structural units of the polyurethane (the content of cyclic structures Cc, nitrogen content CN, and crosslinking equivalent Mc) upon its flammability, expressed in terms of its oxygen index (OI) Thermal stability of crosslinked polyurethanes was not found to influence significantly their thermomechanical properties, while crosslink density and the type and quantity of cyclic structures additionally introduced did have a pronounced effect upon these properties. 相似文献
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The antioxidant properties of alcoholic extracts from the leaves, berries and flowers of Sambucus nigra L. are estimated by means of DPPH and β-carotene/linoleic acid methods, and considered in relation to the extraction temperature (in the range 20-200 °C) and to the level of flavonoids most representative for this plant. The extracts of S. nigra act as antioxidants neutralizing the activities of free radicals and inhibiting the co-oxidation reactions of linoleic acid and β-carotene. There is no direct correlation between the level of flavonoids in the extracts and their antioxidant activity. The data presented show that the extraction temperature strongly influences the antioxidant properties of the extracts, especially in the case of leaves. 相似文献
68.
Kaczyński Łukasz K. Cais-Sokolińska Dorota Szwengiel Artur 《Food science and biotechnology》2019,28(5):1529-1534
Food Science and Biotechnology - The aim of this work was the analysis of galactooligosaccharides (GOS) formation in a model mixture of goat’s milk and its permeate from microfiltration and... 相似文献
69.
Dominika Porbska ukasz Orze Dorota Rutkowska-Zbik Grayna Stochel Rudi van Eldik 《International journal of molecular sciences》2021,22(15)
Besides the well-known functions performed by vitamin B12 (CblCN) in biochemical processes of the human body, an increasing interest has been raised by the possibility of its use as a transmembrane drug carrier, capable, among others, of enhancing the accumulation of inorganic cytostatics in cancer cells. The present study was aimed at determining the possibility of the formation of CblCN conjugates with Pd(II) complexes. A key aspect was their stability, which we attempted to tune by appropriate choice of ligands. Syntheses, spectroscopic analysis of postreaction systems and kinetic investigations of conjugate formation reactions, have been complemented by DFT modelling. The obtained results showed that ligand charge, geometry and electron affinity may have a significant impact on carrier binding and release leading to the activation of the Pd(II) complex. This provides a rationale to expect that with appropriate composition of the coordination sphere, it will be possible to extend the spectrum of less toxic inorganic chemotherapeutics. 相似文献
70.
Joanna Oracz Dorota Zyzelewicz Ewa Nebesny 《Critical reviews in food science and nutrition》2015,55(9):1176-1192
Polyphenols form the largest group of compounds among natural antioxidants, which largely affect the overall antioxidant and antifree radical activity of cocoa beans. The qualitative and quantitative composition of individual fractions of polyphenolic compounds, even within one species, is very diverse and depends on many factors, mainly on the area of cocoa trees cultivation, bean maturity, climatic conditions during growth, and the harvest season and storage time after harvest. Thermal processing of cocoa beans and cocoa derivative products at relatively high temperatures may in addition to favorable physicochemical, microbiological, and organoleptic changes result in a decrease of polyphenols concentration. Technological processing of cocoa beans negatively affects the content of polyphenolic compounds. 相似文献