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These choices are provided new meanings and significance in the experience economy

Adding to this argument is the fact that organic food has provided an alternative to “conventional” food products. Its importance is thus two-fold, as it simultaneously presents itself as an alternative, while – by its mainstream presence and appropriation by consumers – questioning the legitimacy of “conventional” food, on the basis of different essential and previously unquestioned parameters: “Concern about animal welfare is more important for particular organic products and countries where intensive animal farming systems are commonly used. This includes chicken meat and eggs, pork products and, to a lesser extent, beef and dairy products” . This point is also reflected in a 2007 EC report: “The combined benefits of agriculture through the production of safe food, respect of environmental and animal welfare standards is more likely to be selected as important by respondents in most Member States, but particularly northern European countries” . Perceptions of individual health and safety are, still, considered the most important explanatory factors to the consumption of organic foods, which is even the more interesting as organic food products have no documented “extra” positive health effects on the individual’s health when compared to conventionally grown food products . Indeed, individual economic-choice-rationalities , have been shown to be after-rationalisations themselves. Some research suggests instead that the consumption of organic food for most consumers in Western Europe is actually, primarily, motivated by their belief in organic foods’ universal “goodness” . And then, secondly, these beliefs are dressed in the cloak of the “rational” economic optimizing consumer, as post-rationalizations, in order to present oneself as a critical and/or authentic consumer,macetas cultivo or true to ones own tastes . Instead, perceptions relating directly to the environment and overall societal sustainability might play an even larger role than previously assumed when determining what foods to eat or not.

This is perhaps especially true for organic foods, as the procurement of these is never done entirely on price. If this were the case, very few, if any, organic food products would probably be available outside of home gardening; instead organic food is highly dependent on the perceptions of the consumers choosing these: “Perceptions of organic food are affected by their beliefs about the safety and quality of conventional food production and subsequent attitudes to conventional versus organic products. Purchasing behaviour is affected by their perceptions, beliefs, attitudes and the ability to pay premiums for organic products” . The perceptions – not necessarily knowledge – consumers have of agricultural production and its effects on the environment, in general, exercise considerable influence over their final food choices. These issues of place and related values will be explored next. If we are to believe contemporary theory, we live in a “post-modern” “post-industrial” world with all the ontological insecurities this can cause, as already briefly mentioned . The values and meanings inherent in societies are, apparently, shaped not by the present as much as what came before, which probably, also, speaks to the ambiguity of using post-modernism as a “unique” historical category. Indeed, the initial experiences of early twentieth-century industrialization share thematic similarities with the early experience of the, arguably, post-modernist “knowledge” society in the twenty-first century. The alienating effects of urbanity witnessed by Engels and Marx comes into play in the post-modern societies, where the fear of loosing both industry and nature are prevalent. We live in a time where development/progress, be it technical or social, is moving faster than ever before, but also, it seems, is fuelled with more anxieties than before. It is perhaps not surprising if people participating in such societies are looking for authenticity, and associated/related events. Farmers markets, for instance, at once represent something old and something new. It is a re-imagination of the past, legitimized by the beliefs in its intrinsic and real capabilities to effect change in our contemporary food consumption and production. Interestingly, new food experiences and/or consumptive initiatives are, often, legitimized by narratives/perceptions imagined or replicated from the past – they are, in other words, deemed authentic. Authenticity does not have to adhere specifically to linear time, rather place and frequency are significant parameters.

Starbucks is older than New York’s Union Square Farmers Market for instance. But visitors might attach greater authenticity value to the latter than the former due to its “pre-modern” spatiality and perceived sociability. Though it could, reasonably, be argued that Starbucks is a more authentic representation of consumption than the farmers market. Perhaps therefore, or thereof, much attention for the last 10-15 years has been afforded to document the discursive and performative meanings of farmers markets , alternative food systems and outlets often coupled with notions of an emerging “creative countryside,” and not infrequently postulated as part of the perceived development of agriculture in most advanced countries, moving from a productivist to a post-productivist regime , though this concept is, rightly, not without its critics . The recognition and use of authenticity as a concept of meaning and therefore potential agent of change is widespread in contemporary literature, on food experiences , food services , in a tourist perspective , on hospitality , on governance and mediatisation , consumer culture , consumption and consumers , event studies , and within many more areas of research. Its critics are often quick to dismiss authenticity as a backward concept, or a form of left-wing conservatism or defensive localism, reducing ‘the search for authenticity’ to mere marketing strategies, or even a hoax as described by popular author Andrew Potter or in classical Marxist terms an advanced form of “commodity fetishism” or a commodifica-tion of culture – and sometimes rightly so, as authenticity can be utilized for monetary means . But, again, authenticity and its uses is not such a new thing. Outka , in her “Consuming Traditions,” shows how the concept of authenticity was used and misused by different manufacturers and retailers as early as the nineteenth century in order to increase sales and as a promotional tool. Importantly, in the case of Cadbury Outka also shows that the ideal of the authentic was at times, actually, translated into concrete better social conditions for its workers: ‘Wages were better, benefits were greater, the housing was better built’ . The point being, that though food is not something we can very easily ever establish as something completely authentic, its associated values and/or perceptions of authenticity still influence how we understand them and how we choose to consume, for instance. The attempts to bridge the two separate environments of food consumption and production also seem particular to recent times. The huge mainstream success of food writer Michael Pollan and his books is surely an indicator of such holistic interest, along with the mediatisation of “celebrity” alternative farmers like Joel Salatin in a US context. The sentiment guiding these attempts to re-connect food production with its end-consumers, if only on a perceptual level, is eloquently summed up by Vileisis: “Typically, the history of America’s remarkable food system has been recounted as a singularly progressive tale. Yet for many of us, the marvel of fresh leafy lettuce in the winter nests right aside the uneasiness that our children don’t know milk comes from cows” .

In a globalized world with increasing trade of food products, foods might appear to have become more homogenous and standardized as part of the McDonaldization of Society , which, in sentiment, mirrors the “mythic roots” of “massification” , which is often invoked to illustrate the perpetual decline of society. These are perceived developments that have instigated food movements – now themselves globally present – whose primary role is to support local alternatives to what they perceive as a threat to not just nutritional standards and traditional cuisine but also to local culture and communities, to which local food, both its production and consumption, is perceived to have a stabilizing and positive effect, which can counter the influences of the global markets. Again we find a dichotomous and oppositional interpretation of market and community, and the close alignments between global structures as market driven and local structures based and orientated in community. These perceptions of global homogenization and standardization might be influenced by the fact that the global food systems have not brought us less choice but much more, which in itself might trigger responses of insecurity and even anxiety – or the paradox of choice .We apparently live in an “Experience Economy” ,maceta de plastico cuadrada where services and experiences are replacing production as primary economic pursuits, or perhaps more correctly, because of increased productive capabilities and gained efficiencies, more time and money can be spent in the service and leisure industries. Significantly, only eight years should pass until an addition to Pine and Gilmore’s hugely successful book was apparently needed; it was titled “Authenticity: What consumers really want” . “The only thing constant is change” an old saying goes, and in contemporary society in the developed world where knowledge, communication, values and meaning are mediated and often interwoven, the planned event and or experience becomes simultaneously, and paradoxically, the symbol of authenticity and/or something “real” because it is requires a spatial reality and an accelerator/medium for further mediation, change and increased consumption of services and experiences . This call for spatiality could, also, partly, work as an explanatory factor contributing to the rise of food as a symbol and medium. “Food is not only a metaphor or vehicle of communication; a meal is a physical event” reads Mary Douglas’ cautionary warning when food is overtly loaded with cultural symbolism and discourses. Ironically it seems to be exactly the physicality of food that makes it such a potent symbol and/or medium in present society. It both transgresses boundaries and establishes them, and by its tropic nature is always in flux, changeable but stable, intimate to the extreme but part of the mundane features of everyday life. In other words food as medium and mediator is perfect in the experience economy exactly because of these qualities – imagined or otherwise. Food and related experiences can thus be perceived as the perfect “Levinisian” bridge to the “other,” or the closest one gets to an intimate, yet still impersonal, experience in public. Farmers markets, as already mentioned, could thus be perceived as, and actually work as, promoters of community in urban areas, promoting “gemeinschaft”/community but using the cloaks of “gesellschaft”/business for implementation – trying to bridge the dichotomous divide between “gemeinschaft” and “gesellschaft” according to the now classic divide described by Tönnies and Simmel .

This division can, also, reenforce withdrawal. Indeed, the making, of two separate spheres of public and private interaction is noted by Elias, as a “basic condition” of modern civilization: “[W]ith the advance of civilization the lives of human beings are increasingly split between an intimate and a public sphere”. This sentiment, again, carries with it some notions of the supposed decline of community values, or the urban realm as an anti-environment for community, due to its fragmented nature and general anonymity of its participants/inhabitants. It should be noted that Simmel did, also, see the anonymity of urban life as liberating for its participants, exactly due to its impersonal nature. This is a sentiment also found in more recent “urban” sociologist Richard Sennet’s work for whom the complexity and the many different roles afforded to those willing to accept the impersonal nature of urban public life is very rewarding, as it furnishes the self with the complexity of the surrounding objects and people: “[T]he experience of urban life can teach people to live with multiplicity within themselves. The experience of complexity is not just an external event, it reflects back on individuals’ sense of themselves” . Farmers markets, and other related food experiences like food festivals etc., could thus be seen as a contributing factor to the diversity and community of life as they, supposedly, differ from mainstream food outlets in both aesthetics and possible social interaction, as these are often viewed derisively as “non-places” and “Like going to the movies, shopping engaged them in a public culture – but in a private space of their own” . But farmers markets can also work as tools for urban gentrification and symbols of inequality, as participation in these markets often come with a costly prize tag compared to mainstream food outlets like supermarkets: “Their desire for alternative foods, both gourmet and organic, and for ‘middle class’ shopping areas encourages a dynamic of urban redevelopment that displaces working-class and ethnic minority consumers” . Again, the medium of food is shown not to be either inherently good or bad for community, but rather dependent on the context, implementation and aims of its instigators.

Capsules have been used to encapsulate a variety of hydrophobic agrochemicals

Amphiphilicity was invoked by partially functionalizing hydrophobic PSI to form hydrophilic units, allowing for the polymer toself-assemble with a core that sequestered the model water insoluble agricultural compounds: Nile Red, Coumarin, or naphthaleneacetic acid. Upon exposure to alkaline pH, the hydrophobic succinimide portion of the polymer hydrolyzed to water-soluble aspartic acids, and the hydrophobic cargo was released from the now fully hydrophilic polymers. Furthermore, the small size of the nanoparticles and negative surface charge enhanced their internalization into plant cells, demonstrating promise as a smart nanodelivery system for delivery of agrochemicals in plant phloem. Similarly, the Sawamoto and Maynard lab collaborated to create a self-folding, amphiphilic copolymer of trehalose monomer, fluorinated monomer, and PEG monomer.Here, the fluorinated hydrophobic segment enabled the capture of a fluorinated pesticide in water. However, efficient release of the pesticide from the nanoparticles was not demonstrated, so the use of these fluorous interactions for the delivery of agrochemicals needs to be explored further.Liposomes are vesicles with inner aqueous cores surrounded by a lipid bilayer that are stable in aqueous environments, making them effective carriers of hydrophilic cargo.While liposomes have been used for agricultural application, their combination with polymers has been minimally explored, despite promising results. Karny et al. created a 100 nm polymeric liposome and tested for its ability to penetrate and distribute throughout tomato plants. They loaded the system with europium or fluorescein so the bio-distribution of liposomes could be monitored and saw translocation from the plant leaves to the roots and adjacent leaves. In cells,macetas de 5 litros the liposomes were closely associated with the nuclei, and the internalized dye released, staining the entire cell body.

Finally, the liposomes were loaded with Mg or Fe and sprayed onto Mg- and Fe-deficient tomato plants. After two weeks, the tomato plants with these treatments demonstrated significantly improved recovery compared to the commercial control formulations, demonstrating that liposomes could be promising materials for intracellular delivery of plant nutrients.Lin et al. developed a polyelectrolyte complex through electrostatic interactions between a cationic feather keratin and anionic carboxymethyl cellulose to encapsulate hydrophobic insecticide, avermectin.The hydrophobic feather keratin and avermectin assembled in the core of the complexes while the carboxymethyl cellulose polymers assembled on the exterior. Notably, the study demonstrated that as the pH of the release buffer increased, the mechanism of release transitioned from Fick diffusion to non-Fick diffusion. The authors hypothesized that this was due to the negative charge on keratin at higher pHs, resulting in repulsion from chitosan and disassembly of the complex. Polymeric materials have also exploited host-guest chemistry where hydrophobic guest molecules are sequestered in the core of a host molecule with a hydrophobic core and hydrophilic exterior. Chitosan or alginate polymeric nanoparticles functionalized with b-cyclodextrin, a host molecule, have been utilized to form inclusion complexes with hydrophobic and volatile insecticides, carvacrol and/or linalool.While these systems do not rely on self-assembly of the nanoparticles, the addition of b-cyclodextrin to the hydrophilic polymers created an amphiphilic system that captured hydrophobic actives, and the system enhanced the water solubility while decreasing the volatility of these compounds. The system demonstrated high encapsulation efficiencies while being more active against mites than the free insecticides. Micro- and nano- capsules are carriers that are typically made with a hydrophilic, water permeating polymeric shell and lipophilic core which carries hydrophobic cargo.

Capsules with liquid cores are typically created by templating emulsions and traditionally have used toxic emulsifiers and organic solvents.For a more sustainable and green approach, Tang et al. used Pickering emulsions to create polydopamine microcapsules for the encapsulation of an essential oil, turpentine, and pesticide, 4-chloro-2-methylphenoxyacetic acid .Emulsions of turpentine and 2,4-D were stabilized by solid cinnamoyl chloride-modified cellulose nanocrystals and acted as a template to produce the PDA capsules. Both turpentine and 2,4-D were slowly released from the capsule as compared to the free pesticide controls. Another intriguing example of a capsule system utilized proteinoid polymers, produced by the step-growth polymerization of natural and unnatural amino acids, that self-assembled into a nanosized hollow nanoparticle to balance the hydrophobic and hydrophilic components within the proteinoid backbone.This system was implemented for the encapsulation of auxin plant hormones and was externally modified with dodecyl aldehyde or Cyanine3 dye to increase the particle hydrophobicity for better foliar application or allow tracking of the nanoparticles within a plant’s vascular system, respectively. Interestingly, a proteinoid backbone contained a conjugated amino acid herbicide was also tested and found to be toxic to plants without any internalized actives. Previous studies demonstrated that the amino acid is only active in its monomeric form, so the authors hypothesized that the free amino acid herbicide was releasing from the peptide chain via biodegradation. Although this idea was not further explored in this study, other conjugated actives have been explored in agricultural settings. In addition to formulations based on non-covalent interactions, agrochemicals have also benefited from chemically binding to small molecules or polymers which further optimize formulation physicochemical properties, selectivity, and biological activity . Amino acid or glucose conjugation of fungicides and insecticides have improved their plant phloem mobility,lipid-like amphiphilic-conjugates of agrochemicals have induced self-assembling behavior,and hydrophobic moiety conjugates of herbicides have enhanced their water and soil stability.

While some of these conjugation strategies are irreversible, others form reversible linkages which eventually convert to an active parent ingredient , thus improving their selectivity.Traditionally, propesticides are inactive and require a transformation event within the target organism or surrounding environment to release an active chemical. Studies have focused on the chemical linkage of a limited set of agrochemicals containing carboxylic acid, amine, or alcohol functional groups. These groups provide scaffolds to form hydrolytically- or enzymatically-reversible ester or amide linkages. While some of the systems discussed in this section exist in forms discussed in the previous section , these examples are specifically highlighted here for their chemical linkage and cleavage strategies. Agrochemicals with carboxylic acid moieties are hydrophilic in nature and are therefore susceptible to leaching and contaminating groundwater. To prevent these adverse effects, herbicides and plant growth hormones with carboxyl functional groups have been modified with polymers through ester or amide linkages. The herbicides 2-methyl-4-chlorophenoxyacetic acid or 2,4-D have been applied as an anionic initiator for ring opening polymerizations to form ester-linked, end-functionalized degradable polymers.Compared to the free herbicide, these polymers released lower concentrations of the herbicide over time while still effectively preventing weed growth. Additionally, the herbicide-polymer conjugate was incorporated into a biodegradable mulch film, demonstrating the potential functional versatility of polymeric formulations. Through amide or ester linkages, 2,4-D has also been incorporated as a pendant group of a degradable polymeric backbone. One study demonstrated pH-dependent hydrolysis of a combined ester-amide linkage with the herbicide releasing faster in alkaline versus acidic conditions.Another study used a cysteamine- modified 2,4-D, creating an amide linkage and free thiol that could react with PDA nanoparticles via Michael addition.This study compared the release of conjugated 2,4-D and the release of non-conjugated 2,4- D from PDA nanoparticles. They observed a significant difference in the release kinetics, where, over 190 hours, only 10 % of the amide conjugated herbicide released in various pH solutions as opposed to 30-60 % release of 2,4-D when only physically encapsulated. This direct comparison shows release kinetics can be tuned by conjugated agrochemicals. However, the conjugated nanoparticles did adhere less to leaves than their physical encapsulation counterparts, indicating that when some of the PDA catechols are substituted, their adhesive properties diminish.

While these examples focus on the hydrolytic response of the herbicide release and polymer degradation, other reports have demonstrated that herbicide conjugates with amide and ester linkages can also be cleaved when exposed to photochemical or biochemical stimuli. Yin and Yi reported the grafting of 2,4-D to PEG through an ester-linkage to a photo-labile onitrobenzyl group.Due to the amphiphilic nature of the hydrophilic PEG polymer with hydrophobic 2,4-D-modified end group, micelle formation in aqueous conditions was reported. The micelles were photo-responsive, demonstrating no herbicidal release without light irradiation and quantitative release over nine days with solar simulated irradiation. These types of systems also have the potential to increase the water solubility of the hydrophobic active ingredients they carry. Enzymatically-responsive amide-linked systems have also been prepared with gibberellin, plant growth regulator,macetas cultivo conjugated to amino groups on the biopolymer.118 While the conjugate slowly released gibberellin when subjected to hydrolysis, the response was much faster when subjected to amidase or amidohydrolases, enzymes abundant in plants. Moreover, the conjugate improved the solubility of gibberellin and protected it against thermal- and photo-degradation.Similarly, agrochemicals with hydroxyl groups have been conjugated to polymers through ester linkages. In particular, plant growth enhancing brass inosteroid synthetic analogues have been modified with carboxylic acid-containing PEG micelles,chitosan, hyaluronic acid and silk fibroin.Due to the hydrophobicity and quick metabolism in plants of brassinosteroids, their application in agriculture has been limited. However, when modified with PEG, the amphiphilic conjugate forms a micelle in aqueous solutions and establishes controlled release and extendedstabilization of the steroids. Moreover, bio-assays of radish seeds with the conjugate demonstrated increased biomass compared to the unconjugated control. The other polymeric conjugates with biopolymers, silk fibroin, chitosan, and hyaluronic acid, exhibited pH and/or temperature controlled release of the steroids in aqueous solutions. These systems show the modularity available in conjugate systems; various polymers can be utilized with the same agrochemicals as long as they contain a compatible functional groupAgrochemicals with amino groups have also been chemically grafted to carboxyl groups on polymers, forming amide linkages. Emamectin benzoate, a photochemically-labile insecticide with a free amine, was transformed into an acrylamide monomer and co-polymerized with butyl acrylate and methyl methacrylate monomers to form nanoparticles.The nanoparticles dramatically improved the stability of emamectin benzoate with approximately 30 % decomposed after three days under simulated sunlight, compared to 90 % decomposition of the control pesticide.

Additionally, the particles demonstrated enhanced toxicity against Helicorvapa armigera pests compared to free emamectin benzoate. Here, reversibility was not demonstrated, so it is unclear if the conjugate itself is active or if it is a proinsecticide. Another amide conjugate was synthesized through the amino group of kasugamycin, an antibiotic used for plant disease control, and the carboxyls of the biopolymer pectin.The conjugate was stable to UV irradiation and a range of pH and temperatures, but released upon incubation with a pathogenic bacteria that causes melon bacterial angular leaf spot, Pseudomonas syringae pv. lachrymans, due to its enzymatic response.Hydrogels are three-dimensional polymeric networks that hold large quantities of water and have been utilized in a myriad of applications due to their tunable properties. Natural or synthetic polymers can form these scaffolds where synthetic polymers offer more control over gel properties and less batch-to-batch variability than natural polymers.Depending on the functionality of the polymers and implemented cross-linking strategy, synthetic hydrogels have been used for diverse applications such as tissue engineering,drug-delivery,and soil amendments.In particular, they are attractive scaffolds for the encapsulation, stabilization, and controlled-release of water-soluble bio-macromolecules like proteins due to their porous structure and water content. The encapsulation of proteins can occur during hydrogel formation11 or via diffusion into the hydrogel’s pores post-synthesis.The latter method allows for the synthesis of bulk hydrogels, which can later be employed to immobilize a scope of proteins, including enzymes that are used for various industrial applications. In this work, trehalose hydrogels were prepared for the encapsulation of enzymes and subsequent protection to thermal stress, which is known to inactivate proteins often via changes in protein conformation and formation of insoluble aggregates.Trehalose is a disaccharide formed by a,a-1,1-linked glucopyranose units and is upregulated by organisms during prolonged terms of desiccation.The accumulation of trehalose protects proteins,allowing the survival of these organisms in extreme environments including high temperatures. We have previously developed trehalose-functionalized materials for thermostabilization of proteins,including a trehalose hydrogel.However, the yield , scalability, and sustainability of the hydrogel synthesis needed significant improvement to be useful. Herein, we report a scalable trehalose hydrogel synthesis with high yields that employs more environmentally benign solvents. Additionally, the ability of the gel to thermostabilize three major enzymes utilized in animal feed, as well as a relevant enzyme release rate, is described, supporting its potential usefulness for the livestock industry.We reported a straight-forward gel synthesis by first modifying trehalose via Williamson etherification using 4-vinylbenzyl chloride and sodium hydroxide in dimethylsulfoxide to produce mono- or multi-functional styrenyl-trehalose.After a precipitation step to remove DMSO and other impurities and to isolate the crude reaction mixture, the mixture was dried to a yellow powder prior to polymerization in water.