The concept of emergence : a brief history and a philosophical analysis of an ontological regulative principle of organization

Emergence is it is a concept that should undergo more careful philosophical analysis. This paper aims to promote the idea that "emergence" should be taken as an ontological regulative principle (rather than a conceptual instrument able to provide a quick empirical answer to many concrete scientific problems). The usefulness of the proposed approach rests in the fact that it could work as an overarching theoretical framework for the ever-growing body of theories and empirical data provided by natural and social sciences; it could also help to overcome (at least partly) the extreme over-specialization that characterizes contemporary knowledge. Furthermore, it could work as a programmatic framework for comparing and combining data and theories belonging to very different fields - from the natural to the social sciences - but related to one single, very complicated entity, that is, Man. So, after a short history of the concept of emergence, an analysis of its ontological nature will follow; then some specific philosophical problems - like the metaphoric aspects of the emergentist approach, or the ontological unification of every kind of emergence - will be discussed. Afterward this paper will provide a few reasons for supporting a regulative approach to emergence and will illustrate its advantages - supplying an example/proposal taken from the debate about free will

Effect of ultrasounds and high pressure homogenization on the extraction of antioxidant polyphenols from lettuce waste

The possibility to exploit ultrasound (US) and high pressure homogenization (HPH) to obtain ethanolic antioxidant extracts from lettuce waste was studied. The application of US (400\u202fW, 24\u202fkHz) for 120\u202fs led to polyphenol extraction yield (81\u202f\u3bcg/mL) and antioxidant activity (101\u202f\u3bcg\u202fTE/mL) significantly higher than those obtained by traditional solid-liquid extraction at 50\u202f\ub0C for 15\u202fmin. Despite the intense cell rupture effect, the application of HPH pre-treatments resulted in 25% lower phenolic yields as compared to US solely, possibly due to the 40% activation of polyphenoloxidase (PPO) upon HPH treatment. Industrial relevance The waste generated by fresh-cut processing of lettuce poses environmental and economic issues to companies, leading to the need for alternative strategies for its management. US can be successfully exploited as time-saving extraction procedure for obtaining antioxidant extracts from lettuce waste

High-pressure homogenisation combined with blanching to turn lettuce waste into a physically stable juice

Lettuce waste was blanched, ground, pre-homogenised at 40\u202fMPa and subjected to high pressure homogenisation (HPH) at 80 (1 pass) and 150\u202fMPa (1, 10 passes) to obtain an ingredient intended for blended juice formulation. When lettuce was subjected to HPH without previous blanching, physically unstable juices were obtained. By contrast, the combination of HPH with a blanching pre-treatment allowed obtaining juices showing no physical separation and characterised by a bright green colour. This high stability was attributed to the modification of lettuce fibrous structure and to a 90% and 60% inactivation of polyphenoloxidase and pectin methylesterase, respectively. Juices presented a phenolic content of 3.5\u202f\ub1\u202f1.3\u202fmg GAE/100\u202fg and a microbial count at least 1 Log lower than that of corresponding not-blanched samples and below limits usually indicated for juice quality (4.7 Log CFU/g). During storage (4\u202f\ub0C), no phase separation was observed but microbial counts rapidly increased, suggesting the need for a further stabilization step. Industrial application Solid waste generated by fresh-cut processing of lettuce could be valorised by the application of blanching and HPH, leading to an innovative ingredient potentially exploitable in the formulation of healthy blended juices, smoothies and comminuted food. This effort is worth making considering that HPH is being increasingly introduced as processing operation in various industrial contexts, showing good feasibility and cost effectiveness, and could allow valorisation of different leaf discards

Exploring the potentialities of photoinduced glycation to steer protein functionalities: The study case of freeze-dried egg white proteins/carbohydrates mixtures

The capacity of UV-C light to induce glycation and modify functional properties of systems containing freeze-dried egg white proteins and carbohydrates with increasing molecular weight (i.e., glucose, maltose, trehalose and maltodextrin) was studied. Color changes induced by light exposure were taken as typical indicators of glycation. Samples were then analyzed for selected physical (critical concentration, particle size and viscosity), chemical (ovalbumin content) and technofunctional properties (gelling temperature and foaming capacity). The presence of sugars during exposure to UV-C light promoted intense browning and decreased ovalbumin content by circa 30%. Concomitantly, up to a 3-fold increase in critical concentration of the aqueous suspensions of the irradiated protein-carbohydrate powders and changes in particle size were detected. These modifications were consistent with the development of non-enzymatic browning reactions upon UV-C light irradiation. Photoinduced glycation was associated to a decrease in viscosity, a tendency to form gel at temperature lower by up to 8\u25e6C and a better capacity of foam stabilization. The intensity of these changes seems to be affected by the nature of the carbohydrates reacting with proteins, with longer carbohydrates able to produce systems with higher foam stability capacity

Application of different drying techniques to fresh-cut salad waste to obtain food ingredients rich in antioxidants and with high solvent loading capacity

Wastes from iceberg salad fresh-cut processing were submitted to air-drying, freeze-drying, and supercritical-CO2-drying with or without ethanol as co-solvent. Drying was combined with grinding to obtain flours. Samples were analysed for macro- and micro-appearance, particle size, dietary fibre, polyphenol content, antioxidant activity, water vapour sorption, water and oil holding capacity. Air-drying produced a collapsed brown material allowing a flour rich in fibre (>260 g/kg) and polyphenols (3.05 mg GAE/gdw) with antioxidant activity (6.04 OD 123/min/gdw) to be obtained. Freeze-drying maintained vegetable structure and colour while partly retaining polyphenols (1.23 mg GAE/gdw). Supercritical-CO2-drying with ethanol as co-solvent, produced an expanded material able to entrap huge amounts of water and oil (43.2 and 35.2 g of water and oil for g of dry sample). Air-dried salad waste derivatives could be used as functional food ingredients, while supercritical-CO2-dried ones can be exploited as bulking agents and absorbers of oil spills or edible oils. \ua9 2017 Elsevier Lt

Structure of oleogels from \u3ba-carrageenan templates as affected by supercritical-CO2-drying, freeze-drying and lettuce-filler addition

Templates intended for food-grade oleogel production were produced by supercritical-CO2-drying and freezedrying of \u3ba-carrageenan hydrogels (0.4 g/100 g). Supercritical-CO2-drying produced hard (61 N firmness) and shrunk oleogels, which presented 80% oil content and no oil release. Freeze-drying allowed obtaining soft (2 N) oleogels, with 97% oil content but presenting a high oil release (49%). Lettuce homogenate, used as water phase of the hydrogel, acted as inactive filler agent of template network. It allowed reducing shrinkage and firmness (10 N) of supercritical-CO2-dried oleogels, which presented 94% oil content and 5% oil release. In the case of freeze-dried templates, lettuce-filler increased firmness (4 N) but reduced oil release (34%). SEM image analysis highlighted that the physical properties of \u3ba-carrageenan oleogels can be explained based on the effect of drying technique and lettuce-filler addition on the porous microstructure of the dried templates

Innovative bioaerogel-like materials from fresh-cut salad waste via supercritical-CO2-drying

Fresh-cut salad waste was dried by means of supercritical carbon dioxide technology using ethanol as co-solvent. The obtained material was characterized by a white color and a brittle texture. Microscopic images revealed an aerated structure, with well-evident intra and inter-cellular spaces. Based on the high internal surface (> 100m2/g), the extremely low density ( 80%), supercritical-dried salad waste can be regarded as a bioaerogel-like material. One gram of this material absorbed 33 and 19 g of water and oil respectively. Industrial application: Fresh-cut processing of salad generates large amounts of solid waste which is not suitable for conversion into biogas or fertilizers. This waste poses management issues for producers and represents an environmental burden. Fresh-cut salad waste could be valorized to produce bioaerogel-like materials with enhanced solvent uptake ability, to be exploited as food ingredients, packaging, absorbents or innovative carriers for both lipophilic and hydrophilic compounds

Effect of Hyperbaric Storage at Room Temperature on the Activity of Polyphenoloxidase in Model Systems and Fresh Apple Juice

The effect of hyperbaric storage (HS) on polyphenoloxidase activity (PPO) was studied in model solutions and apple juice. Model solutions containing increasing amounts of mushroom (Agaricus bisporus) PPO (up to 26 U) were stored at room temperature at pressure up to 200 MPa. During HS, samples were assessed for residual PPO activity. The enzyme was completely inactivated according to a first-order kinetic model that was used to calculate PPO decimal reduction time (Dp) and pressure sensitivity (zp = 140.8 MPa) in diluted model solutions (2 U PPO). The increase in enzyme concentration (6–26 U) nullified the effect of HS, probably due to protein structure stabilization by self-crowding. The application of HS at 100 and 200 MPa to apple juice promoted a decrease in total bacteria, lactic acid bacteria, yeasts, and molds. These changes occurred in concomitance with the inactivation of PPO (zp = 227.3 MPa). At 200 MPa, PPO inactivation followed a biphasic first-order kinetic, suggesting the presence of PPO isozymes with different pressure sensitivity. The inactivation of PPO was observed to occur more rapidly with increasing storage pressure and led to the maintenance of the original bright juice color. This study proves the capability of HS to control enzyme-related quality decay in fruit juices and, potentially, in many other food matrices suffering enzymatic alteration

Controlling aerogel surface porosity to enhance functionality in foods

Aerogels based on biopolymers, such as proteins, are food-grade materials characterized by distinctive physical properties, which make them intriguing candidates for the development of new ingredients with unique functionalities. The aerogel typical aerated structure can be exploited to deliver health-protecting bioactives or reduce food calories by increasing air content. However, aerogel porosity is easily lost upon contact with liquid food ingredients (water and oil). This issue might be overcome by closing the pores at the aerogel surface. In this work, processing and formulation strategies were applied to increase the structural stability of whey protein aerogels obtained by traditional ethanol exchange and supercritical-CO2-drying. Aerogels characterized by different levels of surface collapse were obtained by subjecting alcolgels to a controlled ethanol evaporation procedure prior to supercritical-CO2-drying. Alternatively, aerogels were coated with hydrophilic (alginate, agar) or hydrophobic (ethylcellulose) polymers. Aerogel microstructure was studied by SEM. Water and oil absorption kinetics were then measured. Ethanol evaporation time, polymer concentration and gelation rate were identified as key parameters affecting aerogel surface structure, allowing to significantly decrease water and oil absorption kinetics in the aerogels. This study suggests that aerogel structure-driven functionalities could be maintained in complex food formulations by controlling aerogel surface porosity

La Rivincita del Professore Ludwig von Bertalanffy: Verso una nuova immagine dell'uomo

La tesi si propone di illustrare la vicenda intellettuale di Ludwig von Bertalanffy, con particolare riferimento allo sviluppo della sua antropologia filosofica e all'accoglienza (o meglio al fraintendimento) di quest'ultima da parte del movimento sistemico americano e della psicologia umanistica sviluppatasi negli Stati Uniti nel secondo dopoguerra