Stability and consumer acceptance of long-chain omega-3 fatty acids (eicosapentaenoic acid, 20:5, n-3 and docosahexaenoic acid, 22:6, n-3) in cream-filled sandwich cookies

ABSTRACT:  We formulated a filling for sandwich cookies containing 400 mg of eicosapentaenoic acid, 20:5, n-3 (EPA) + docosahexaenoic acid, 22:6, n-3 (DHA) encapsulated in a matrix of starch and gelatin. Cookies were stored at 2 different temperatures (18 °C and 35 °C) and under 2 different packaging conditions (atmospheric and vacuum packed) for 28 d. At regular intervals, cookies were analyzed for moisture, water activity, and concentrations of EPA, DHA, and dienes. Results showed that there were no significant losses of EPA and DHA during storage under the conditions of study. A maximum loss of 5% was observed after 28 d of storage. The concentration of dienes obtained under different conditions were low (< 25 mmol/kg) as compared to a salmon oil sample with appreciable signs of oxidation (600 mmol/kg). Sensory evaluation of cookies by an untrained panel of healthy consumers and ulcerative colitis patients revealed no aftertaste and high acceptability of the cookies. Our results demonstrated that it is possible to make shelf-stable fortified foods with high levels of long-chain ω3FA.     

CFD‐Simulation der Feststoffeinbindung in einen Sprühstrahl

Sound‐absorbing mats consisting of cross‐linked Polyurethane (PUR) foam and metal reinforcements, door panels and centre consoles for the interior of vehicles became important products for automotive component suppliers. The leading technology for the production of foam on the base of PUR with noise absorbing properties is the application of powder insertion (e.g. metal) in the PUR spray. The numerical simulation (CFD) of the spray including the particle‐droplet interaction is presented. The theoretical background of the implemented models is explained and the experimental results achieved with a pilot plant are compared with the numerical results. The presented simulation offers the possibility to suitably predict the metal powder distribution in a PUR spray.     

Fast kd‐tree‐based hierarchical radiosity for radiative heat transport problems

In this paper we present a new efficient approach for radiative heat transfer simulations for various applications in engineering, combining existing approaches from different fields of computer science and heat transfer. For these application fields we assume radiative exchange between gray, diffuse surfaces in a radiatively nonparticipating medium. To solve the complex space–time behavior of radiation in 3D domains we use the hierarchical radiosity method. Here, the basic idea is to hierarchically subdivide surfaces forming a quad‐tree structure until a refinement criterion is reached. The fundamental underlying operation of the radiosity method is visibility detection which can be solved efficiently by using a space partitioning approach for the input surfaces. For this reason we choose a kd‐tree which is the best known acceleration structure for visibility detection on irregularly distributed surfaces. These approaches dramatically decrease the complexity of the radiation problem from n³ to O((k² + n)logk), where k is the number of input surfaces and n is the number of refined surfaces. We validate the approach for several non‐trivial examples and demonstrate that the scheme is second‐order accurate. Copyright © 2011 John Wiley & Sons, Ltd.     

Fluorophore-Labeled Cyclic Nucleotides as Potent Agonists of Cyclic Nucleotide-Regulated Ion Channels

High-affinity fluorescent derivatives of cyclic adenosine and guanosine monophosphate are powerful tools for investigating their natural targets. Cyclic nucleotide-regulated ion channels belong to these targets and are vital for many signal transduction processes, such as vision and olfaction. The relation of ligand binding to activation gating is still challenging, and there is a need for fluorescent probes that enable the process to be broken down to the single-molecule level. This inspired us to prepare fluorophore-labeled cyclic nucleotides, which are composed of a bright dye and a nucleotide derivative with a thiophenol motif at position 8 that has already been shown to enable superior binding affinity. These bioconjugates were prepared by a novel cross-linking strategy that involves substitution of the nucleobase with a modified thiophenolate in good yield. Both fluorescent nucleotides are potent activators of different cyclic nucleotide-regulated ion channels with respect to the natural ligand and previously reported substances. Molecular docking of the probes excluding the fluorophore reveals that the high potency can be attributed to additional hydrophobic and cation-π interactions between the ligand and the protein. Moreover, the introduced substances have the potential to investigate related target proteins, such as cAMP- and cGMP-dependent protein kinases, exchange proteins directly activated by cAMP or phosphodiesterases.     

Simultaneous impact modified and chain extended glass fiber reinforced poly(lactic acid) composites: Mechanical,thermal, crystallization,and dynamic mechanical performance

Herein, glass fiber (GF) reinforced binary, ternary, and quaternary poly(lactic acid) (PLA) composites were prepared. Toughening, and chain extension of PLA was achieved through the incorporation of impact modifier and chain extender and their concurrent effects on the spectroscopic, crystallization, mechanical, thermal, and thermomechanical properties of the composites were investigated. High mechanical properties of GF influenced the mechanical performance of the composites. However, GF alone could not restrict the chain mobility of PLA due to poor interface and low crystallization activities in the PLA-GF composite. Incorporation of impact modifier and chain extender produced significantly enhanced interaction between GF and PLA. Significantly, the crystallinity, impact strength, and flexural modulus of PLA in the quaternary composite were increased by 58%, 63%, and 66%, respectively. In addition, damping and effectiveness coefficient of the PLA-GF composite were notably reduced by the simultaneous impact modification and chain extension of the reinforced composites.     

Pristine point of zero charge (p.p.z.c.) and zeta potentials of boehmite’s nanolayer and nanofiber surfaces

The pristine point of zero charge (p.p.z.c) and zeta potential as a function of pH of boehmite oxide/hydroxide (α-Al₂O₃·H₂O) have been determined for three filter media. The active component in the first two filter media is boehmite nanofibers, only 2 nm in diameter and about 300 nm long. Boehmite nanofibers create high zeta potential (ζ_true≥46 mV) in aqueous solutions in the pH range of 3–8. The p.p.z.c. values were determined to be 11.60 ± 0.15 for nanofibers grafted onto microglass fibers and 11.40 ± 0.15 for agglomerated nanofibers. In the third filter media, a boehmite nanolayer in the form of monocrystalline oxide/hydroxide with a thickness of approximately 1.2 nm is electroadhesively deposited onto siliceous support material with large surface area of about 50 m²/g, therefore forming a highly electropositive composite of boehmite nanolayer on the second highly electronegative solid. Boehmite’s oxide-hydroxide nanolayer surface creates high zeta potential (ζ_true≥50 mV) in aqueous solutions in the pH range of 3–8. The p.p.z.c. value was determined to be 11.38 ± 0.15. The reported values are within accuracy, but they are much higher than the values reported in the literature. X-ray powder diffraction data were supplemented by microscopy, infrared spectroscopy in order to characterize fully synthetic boehmite surfaces.