In this study, the effect of two amylases (maltogenic amylase and maltotetraose-producing amylase) on the rheological properties of wheat flour as well as on the quality and staling of partially baked bread is investigated. The rheological measurements obtained from a Viscograph showed that both amylases reduced the peak viscosity, final viscosity, and setback viscosity of wheat flour, whereas maltotetraose-producing amylase significantly improved the specific volume of fresh bread. Furthermore, the addition of both types of amylases was able to reduce crumb firmness and amylopectin retrogradation, due to their ability to partially hydrolyze starch molecules and generate low molecular weight dextrin, which was confirmed by the analysis of the maltooligosaccharide composition of the breads. The results indicated that the effects of maltotetraose-producing amylase were more pronounced than those of maltogenic amylase in terms of slowing bread staling.

Immer wieder ertont in der Praxis und in der politischen Diskussion der Ruf nach einem «Integrativen Management». Schon die klassische Managementforschung, allen voran Peter Drucker, verlangt und verfolgt einen integrativen Ansatz. Denn die Integration verschiedener Funktionen, aber auch Stakeholder‐Interessen oder Entwicklungshorizonte scheint fur eine wirkungs‐ und verantwortungsvolle Unternehmensfuhrung ein unerlasslicher Erfolgsfaktor. Diese Integrationsleistung muss spatestens auf der Ebene des Top‐Managements geleistet werden. Umgekehrt ist heute ein grosser Teil der Management‐Forschung und auch der Management‐Ausbildung funktional (z.B. HR, Controlling, Marketing)und perspektivisch(z.B. Shareholder Value oder totale Kundenorientierung) ausgerichtet. Es fragt sich, was Managementforschung heute fur die Fuhrungspraxis, die integrativ «managen» muss, leisten kann, und wie Betriebswirtschaftslehre mit einem Anspruch auf integratives Management unterrichtet werden soll, und wie integratives Management definiert werden kann. Dieses Papier begrundet den Bedarf an integrativem Management, analysiert die heutige Entwicklung in Richtung disziplinarer/funktionaler Managementforschung, exploriert Zugange zu Integration insbesondere auf der Basis der St. Galler Managementforschung,sucht Anschlusspunkte in der internationalen Managementforschung und entwickelt Optionen fur die «Kunden» der Managementforschung, das Management und die Managementausbildung. Dabei wird integratives Management definiert als eine Gestaltung und Fuhrung von Organisationen als soziotechnische Systeme, die wesentliche Spannungsfelder und Zielkonflikte bewusst und verantwortungsvoll behandelt. Als solche Spannungsfelder werden aus der Theorie und einer qualitativen Befragung von Fuhrungskraften u.a. der Umgang mit den verschiedenen Stakeholder‐Interessen, die ubergreifende Koordination der verschiedenen Funktionen oder die Abstimmung zwischen kurzfristigen im Vergleich zu langfristigen Zielen identifiziert.

Der Tradition der St. Galler Management-Modelle folgend wird in diesem Lehrbuch Management als Funktion und Tätigkeit behandelt. Dabei werden zentrale Konzepte des Managements, der Entscheidungstheorie, der Strategie, der Führung, der Organisation und der Governance aufgegriffen. Im Vordergrund stehen zentrale Spannungsfelder des Managements und die Vermittlung modellhafter Überblicke.

Tuning the rheological properties of surfactant solutions by charge screening is a convenient formulation tool in cosmetic, household, oil recovery, drag-reduction, and thickening applications. Surfactants self-assemble in water, and upon charge screening and core shielding, they grow into long wormlike micelles (WLMs). These are valuable model systems for soft matter physics, and the most explored formulation is hexadecyl-trimethylammonium bromide (CTAB) and sodium salicylate (NaSal). Replacing NaSal with aromatic salts of altered hydrophobicity results in different penetration of the additive in the CTAB micellar core. This altered penetration depth will determine the anisotropic micellar growth that tailors the viscoelastic response. Sodium 4-methylsalicylate (mNaSal) is a higher hydrophobicity alternative to NaSal, requiring less additive to induce strong changes in the viscoelastic properties. Herein, we provide a comparative study of the mNaSal/CTAB system with the reference NaSal/CTAB over a range of temperatures and salt concentrations. The findings from the well-known NaSal/CTAB pair are transferred to the mNaSal/CTAB system, revealing the origins of the WLM solution's viscoelastic properties by discerning contributions from charge screening and micellar core shielding upon small differences in hydrophobicity.

Following the tradition of the St. Gallen management models, this textbook explores management as a function and as an activity. It covers the key concepts of management, decision theory, strategy, leadership, organization and governance. It focuses on the central fields of tension in management and includes various illustrative models.

Crust treatments, namely edible bread coatings, enzymatic crust modification and chemical crust modification, were introduced with the intention to minimize bread water loss during ambient storage. It was observed that compared to the treated bread, the untreated bread had significantly higher weight loss and crumb firmness after 14 days of ambient storage. A large array of materials was tested, among which hydrophobic coatings were shown to have the highest moisture barrier efficiency. In particular, the 20% candelilla wax coating (solution of 20% candelilla wax in sunflower oil), 20% beeswax coating (solution of 20% beeswax in sunflower oil) and HPMC oleogel coating (coating containing hydroxypropyl methyl cellulose oleogel) were proved to be most effective, thanks to their low affinity with water and low water vapor permeability. The application of the 20% candelilla wax coating resulted in reductions of the bread weight loss from about 30 to 13% and the crumb firmness from above 500 to 34 ​N after a storage period of 14 days. In addition, it was noted that the enzymatic and chemical crust modifications yielded moderately good results, but showed a significantly altered appearance of the bread crust.

Intermolecular interactions are responsible for the macroscopic properties of materials. Self-assembled micelles of ionic surfactants in the presence of salt are a result of the balance between hydrophobic-hydrophilic and ionic forces. For example, sodium salicylate (NaSal) undoubtedly offers a powerful means of increasing the viscoelasticity of hexadecyl trimethylammonium bromide (CTAB) solutions by orders of magnitude, which results from the formation of wormlike micelles (WLMs). The efficiency of this additive relies on its ability to integrate and alter the repulsive interactions governing CTAB micelles. Consequently, small modifications in the molecular structure of NaSal influences the nature of these interactions. Nevertheless, the full potential of formulation for tailoring the system’s viscoelasticity has yet to be unleashed. Herein, we investigate a series of structurally similar molecules varying in terms of geometry and size. The depth and molecular orientation of their insertion into the micellar core were monitored by proton nuclear magnetic resonance (1H-NMR) and correlated with the corresponding viscoelastic response. After detailed observation of the impact of molecular interactions on zero-shear viscosity η0, we discuss it in terms of the effective packing parameter (PPeff). All the investigated additives increased PPeff, triggering anisotropic micellar growth toward WLMs. The simplicity of our approach is attractive for predicting and controlling the viscoelastic properties of WLM solutions from an intermolecular level.

Chia seeds and their mucilage gels provide a nutritionally and functionally promising ingredient for the food and pharmaceutical industry. Application and utilization of the gel remain limited due to the tightly adhesion of the mucilage to the seeds, which affects the organoleptic properties, control of concentration and structuring possibilities. To exploit the full potential of chia mucilage gels as a functional ingredient calls for separation and purification of the gel. Herein, the gel was extracted by centrifugation and characterized rheologically and microscopically to link the viscoelastic properties to the structural properties. Subsequently, the gel was dried employing three different methods for facilitated storage and prolonged shelf life. The dried gels were readily soluble and its viscoelastic properties were fully regenerated upon rehydration demonstrating its potential to envisage industrial applications. The viscoelastic chia mucilage demonstrated shear-thinning behavior with complete relaxation upon stress removal. The gel's elasticity was enhanced with increasing mucilage concentration resulting in a highly tunable system. The extractable and rehydratable functional chia gel is a viable candidate as additive for the development of products requiring specific viscoelastic properties. Addition of the gel enhances the nutritional profile without interfering with the organoleptic properties.

Bicelles are tunable disk-like polymolecular assemblies formed from a large variety of lipid mixtures. Applications range from membrane protein structural studies by nuclear magnetic resonance (NMR) to nanotechnological developments including the formation of optically active and magnetically switchable gels. Such technologies require high control of the assembly size, magnetic response and thermal resistance. Mixtures of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and its lanthanide ion (Ln3+) chelating phospholipid conjugate, 1,2-dimyristoyl-sn-glycero-3-phospho-ethanolamine-diethylene triaminepentaacetate (DMPE-DTPA), assemble into highly magnetically responsive assemblies such as DMPC/DMPE-DTPA/Ln3+ (molar ratio 4:1:1) bicelles. Introduction of cholesterol (Chol-OH) and steroid derivatives in the bilayer results in another set of assemblies offering unique physico-chemical properties. For a given lipid composition, the magnetic alignability is proportional to the bicelle size. The complexation of Ln3+ results in unprecedented magnetic responses in terms of both magnitude and alignment direction. The thermo-reversible collapse of the disk-like structures into vesicles upon heating allows tailoring of the assemblies' dimensions by extrusion through membrane filters with defined pore sizes. The magnetically alignable bicelles are regenerated by cooling to 5 °C, resulting in assembly dimensions defined by the vesicle precursors. Herein, this fabrication procedure is explained and the magnetic alignability of the assemblies is quantified by birefringence measurements under a 5.5 T magnetic field. The birefringence signal, originating from the phospholipid bilayer, further enables monitoring of polymolecular changes occurring in the bilayer. This simple technique is complementary to NMR experiments that are commonly employed to characterize bicelles.

Enzymatic browning primarily affects fruits and vegetables but also occurs in wheat-based food. Herein, the browning behavior in wheat pastry dough was investigated aiming toward a targeted inhibitory treatment without influencing the pastry dough properties such as workability or taste. Dough discoloration is attributed to several subsequent enzyme-substrate reactions, which can selectively be inhibited by food additives. In most cases, an effective and lasting inhibition is only guaranteed by compounds acting upon multiple inhibition pathways. Despite their effectiveness, the unlimited use of commercial inhibitors is nondesirable due to necessary labeling, thus sustainable and natural inhibitors usually occurring as conventional food ingredients are of interest. It is shown that white wine combined with lemon juice revealed itself as an ideal combination for prevention of enzymatic browning in pastry dough.

The adsorption of protein layers at oil-water interfaces is critical to the formation and stability of various emulsions in, for example, technical applications as well as in biological lipid storage. Effects of ionic strength, pH, temperature, and pretreatments of the proteins are well-known. However, the oil phase has been regarded as exchangeable and its role in protein adsorption has been widely ignored. Herein, the influence of systematically selected oil interfaces of high purity on the formation and properties of β-lactoglobulin (β-lg) adsorption layers was evaluated. Droplet profile tensiometry and interfacial rheometry were employed to determine the adsorption kinetics and dilatational and interfacial shear moduli. We show that depending on the molecular size, flexibility, hydrophobicity, polarity, and polarizability of the oils, globular proteins adsorb distinctively. Stronger interactions of polar oils with the hydrophilic exterior of the native β-lg lead to decelerated protein unfolding. This results in lower surface pressures and slower formation of viscoelastic networks. In addition, polar oils interact stronger with the protein network by hydrophilic bonding and thereby act as softening agents. The observed effects of hydrophobic subphases on the adsorbed protein layers provide knowledge, which promotes higher reproducibility in rheological studies and precise tailoring of interfacial films for enhanced formation and stability of emulsions.

Cellulose nanocrystals (CNCs) are an emerging natural material with the ability to stabilize fluid/fluid interfaces. Native CNC is hydrophilic and does not change the interfacial tension of the stabilized emulsion or foam system. In this study, rodlike cellulose particles were isolated from hemp and chemically modified to alter their hydrophobicity, i.e., their surface activity, which was demonstrated by surface tension measurements of the particles at the air/water interface. The buildup and mechanical strength of the interfacial structure were investigated using interfacial shear and dilatational rheometry. In contrast to most particle or protein-based interfacial adsorption layers, we observe in shear flow a Maxwellian behavior instead of a glasslike frequency response. The slow and reversible buildup of the layer and its unique frequency dependence indicate a weakly aggregated system, which depends on the hydrophobicity and, thus, on the contact angle of the CNC particles at the air/water interface. Exposed to dilatational flow, the weakly aggregated particles cluster and form compact structures. The interfacial structure generated by the different flow fields is characterized by the contact angle, immersion depth, and layer roughness obtained by neutron reflectometry with contrast variation while the size and local structural arrangement of the CNC particles were investigated by AFM imaging.

We present a nonlinear rheological investigation of model rod-like particles at the air/water interface in dilatation and shear. Cellulose nanocrystals were modified to vary their surface hydrophobicity, creating a range of surface-active particles with varying contact angle. The interfacial rheological properties were studied using a series of frequency sweeps in small amplitude oscillatory shear as well as strain sweeps under large amplitude oscillatory shear (LAOS) and large amplitude oscillatory dilatation (LAOD) to include the nonlinear behavior. A multi-mode Maxwell model was used to fit the frequency sweeps that were obtained during formation of the interfacial layer. A shift toward longer relaxation times was found, more pronounced for particles with higher hydrophobicity. Lissajous plots in LAOS revealed strain stiffening, yielding, and unconstrained flow of the interfacial layers. Lissajous plots in LAOD revealed strain hardening in compression and strain softening in expansion, increasing with surface pressure and with particle hydrophobicity. While interfacial layers commonly show gel or solid-like behavior, our findings imply a weakly aggregated system. The rheological behavior indicates the formation of larger clusters for particles with high hydrophobicity compared to smaller clusters for particles with low hydrophobicity. The particle-particle interactions therefore vary with hydrophobicity, suggesting that capillary interactions are important for the formation of these microstructures. Published by AIP Publishing.

Hydrogels delivering on-demand tailorable optical properties are formidable smart materials with promising perspectives in numerous fields, including the development of modern sensors and switches, the essential quality criterion being a defined and readily measured response to environmental changes. Lanthanide ion (Ln3+)-chelating bicelles are interesting building blocks for such materials because of their magnetic responsive nature. Imbedding these phospholipid-based nanodiscs in a magnetically aligned state in gelatin permits an orientation-dependent retardation of polarized light. The resulting tailorable anisotropy gives the gel a well-defined optical signature observed as a birefringence signal. These phenomena were only reported for a single bicelle-gelatin pair and required high magnetic field strengths of 8 T. Herein, we demonstrate the versatility and enhance the viability of this technology with a new generation of aminocholesterol (Chol-NH2)-doped bicelles imbedded in two different types of gelatin. The highly magnetically responsive nature of the bicelles allowed to gel the anisotropy at commercially viable magnetic field strengths between 1 and 3 T. Thermoreversible gels with a unique optical signature were generated by exposing the system to various temperature conditions and external magnetic field strengths. The resulting optical properties were a signature of the gel's environmental history, effectively acting as a sensor. Solutions containing the bicelles simultaneously aligning parallel and perpendicular to the magnetic field directions were obtained by mixing samples chelating Tm3+ and Dy3+. These systems were successfully gelled, providing a material with two distinct temperature-dependent optical characteristics. The high degree of tunability in the magnetic response of the bicelles enables encryption of the gel's optical properties. The proposed gels are viable candidates for temperature tracking of sensitive goods and provide numerous perspectives for future development of tomorrow's smart materials and technologies.

The magnetic susceptibility of lanthanide-chelating bicelles was selectively enhanced by introducing 3β-amino-5-cholestene (aminocholesterol, Chol-NH2) in the bilayer. Unprecedented magnetic alignment of the bicelles was achieved without altering their size. An aminocholesterol conjugate (Chol-C2OC2-NH2), in combination with different lanthanide ions, offers the possibility of fine-tuning the bicelle's magnetic susceptibility.

Mixtures of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and its lanthanide ion (Ln3+) chelating phospholipid conjugate, 1,2-dimyristoyl-sn-glycero-3-phospho-ethanolamine-diethylene triaminepentaacetate (DMPE-DTPA), assemble into highly magnetically responsive polymolecular assemblies such as DMPC/DMPE-DTPA/Ln3+ (molar ratio 4:1:1) bicelles. Their geometry and magnetic alignability is enhanced by introducing cholesterol into the bilayer in DMPC/Cholesterol/DMPE-DTPA/Ln3+ (molar ratio 16:4:5:5). However, the reported fabrication procedures remain tedious and limit the generation of highly magnetically alignable species. Herein, a simplified procedure where freeze thawing cycles and extrusion are replaced by gentle heating and cooling cycles for the hydration of the dry lipid film was developed. Heating above the phase transition temperature Tm of the lipids composing the bilayer before cooling back below the Tm was essential to guarantee successful formation of the polymolecular assemblies composed of DMPC/DMPE-DTPA/Ln3+ (molar ratio 4:1:1). Planar polymolecular assemblies in the size range of hundreds of nanometers are achieved and deliver unprecedented gains in magnetic response. The proposed heating and cooling procedure further allowed to regenerate the highly magnetically alignable DMPC/Cholesterol/DMPE-DTPA/Ln3+ (molar ratio 16:4:5:5) species after storage for one month frozen at -18 °C. The simplicity and viability of the proposed fabrication procedure offers a new set of highly magnetically responsive lanthanide ion chelating phospholipid polymolecular assemblies as building blocks for the smart soft materials of tomorrow.

Wormlike micellar aggregates formed from the mixture of ionic surfactants with aromatic additives result in solutions with impressive viscoelastic properties. These properties are of high interest for numerous industrial applications and are often used as model systems for soft matter physics. However, robust and simple models for tailoring the viscoelastic response of the solution based on the molecular structure of the employed additive are required to fully exploit the potential of these systems. We address this shortcoming with a modified packing parameter based model, considering the additive-surfactant pair. The role of charge neutralization on anisotropic micellar growth was investigated with derivatives of sodium salicylate. The impact of the additives on the morphology of the micellar aggregates is explained from the molecular level to the macroscopic viscoelasticity. Changes in the micelle's volume, headgroup area and additive structure are explored to redefine the packing parameter. Uncharged additives penetrated deeper into the hydrophobic region of the micelle, whilst charged additives remained trapped in the polar region, as revealed by a combination of 1H-NMR, SAXS and rheological measurements. A deeper penetration of the additives densified the hydrophobic core of the micelle and induced anisotropic growth by increasing the effective volume of the additive-surfactant pair. This phenomenon largely influenced the viscosity of the solutions. Partially penetrating additives reduced the electrostatic repulsions between surfactant headgroups and neighboring micelles. The resulting increased network density governed the elasticity of the solutions. Considering a packing parameter composed of the additive-surfactant pair proved to be a facile means of engineering the viscoelastic response of surfactant solutions. The self-assembly of the wormlike micellar aggregates could be tailored to desired morphologies resulting in a specific and predictable rheological response.