986 resultados para Food restriction


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This report derives from the EU funded research project “Key Factors Influencing Economic Relationships and Communication in European Food Chains” (FOODCOMM). The research consortium consisted of the following organisations: University of Bonn (UNI BONN), Department of Agricultural and Food Marketing Research (overall project co-ordination); Institute of Agricultural Development in Central and Eastern Europe (IAMO), Department for Agricultural Markets, Marketing and World Agricultural Trade, Halle (Saale), Germany; University of Helsinki, Ruralia Institute Seinäjoki Unit, Finland; Scottish Agricultural College (SAC), Food Marketing Research Team - Land Economy Research Group, Edinburgh and Aberdeen; Ashtown Food Research Centre (AFRC), Teagasc, Food Marketing Unit, Dublin; Institute of Agricultural & Food Economics (IAFE), Department of Market Analysis and Food Processing, Warsaw and Government of Aragon, Center for Agro-Food Research and Technology (CITA), Zaragoza, Spain. The aim of the FOODCOMM project was to examine the role (prevalence, necessity and significance) of economic relationships in selected European food chains and to identify the economic, social and cultural factors which influence co-ordination within these chains. The research project considered meat and cereal commodities in six different European countries (Finland, Germany, Ireland, Poland, Spain, UK/Scotland) and was commissioned against a background of changing European food markets. The research project as a whole consisted of seven different work packages. This report presents the results of qualitative research conducted for work package 5 (WP5) in the pig meat and rye bread chains in Finland. Ruralia Institute would like to give special thanks for all the individuals and companies that kindly gave up their time to take part in the study. Their input has been invaluable to the project. The contribution of research assistant Sanna-Helena Rantala was significant in the data gathering. FOODCOMM project was coordinated by the University of Bonn, Department of Agricultural and Food Market Research. Special thanks especially to Professor Monika Hartmann for acting as the project leader of FOODCOMM.

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The nutritional quality of the product as well as other quality attributes like microbiological and sensory quality are essential factors in baby food industry, and therefore different alternative sterilizing methods for conventional heating processes are of great interest in this food sector. This report gives an overview on different sterilization techniques for baby food. The report is a part of the work done in work package 3 ”QACCP Analysis Processing: Quality – driven distribution and processing chain analysis“ in the Core Organic ERANET project called Quality analysis of critical control points within the whole food chain and their impact on food quality, safety and health (QACCP). The overall objective of the project is to optimise organic production and processing in order to improve food safety as well as nutritional quality and increase health promoting aspects in consumer products. The approach will be a chain analysis approach which addresses the link between farm and fork and backwards from fork to farm. The objective is to improve product related quality management in farming (towards testing food authenticity) and processing (towards food authenticity and sustainable processes. The articles in this volume do not necessarily reflect the Core Organic ERANET’s views and in no way anticipate the Core Organic ERANET’s future policy in this area. The contents of the articles in this volume are the sole responsibility of the authors. The information contained here in, including any expression of opinion and any projection or forecast, has been obtained from sources believed by the authors to be reliable but is not guaranteed as to accuracy or completeness. The information is supplied without obligation and on the understanding that any person who acts upon it or otherwise changes his/her position in reliance thereon does so entirely at his/her own risk. The writers gratefully acknowledge the financial support from the Core Organic Funding Body: Ministry of Agriculture and Forestry, Finland, Swiss Federal Office for Agriculture, Switzerland and Federal Ministry of Consumer Protection, Food and Agriculture, Germany.

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The aim of this report is to discuss the role of the relationship type and communication in two Finnish food chains, namely the pig meat-to-sausage (pig meat chain) and the cereal-to-rye bread (rye chain) chains. Furthermore, the objective is to examine those factors influencing the choice of a relationship type and the sustainability of a business relationship. Altogether 1808 questionnaires were sent to producers, processors and retailers operating in these two chains of which 224 usable questionnaires were returned (the response rate being 12.4%). The great majority of the respondents (98.7%) were small businesses employing less than 50 people. Almost 70 per cent of the respondents were farmers. In both chains, formal contracts were stated to be the most important relationship type used with business partners. Although for many businesses written contracts are a common business practice, the essential role of the contracts was the security they provide regarding the demand/supply and quality issues. Relative to the choice of the relationship types, the main difference between the two chains emerged especially with the prevalence of spot markets and financial participation arrangements. The usage of spot markets was significantly more common in the rye chain when compared to the pig meat chain, while, on the other hand, financial participation arrangements were much more common among the businesses in the pig meat chain than in the rye chain. Furthermore, the analysis showed that most of the businesses in the pig meat chain claimed not to be free to choose the relationship type they use. Especially membership in a co-operative and practices of a business partner were mentioned as the reasons limiting this freedom of choice. The main business relations in both chains were described as having a long-term orientation and being based on formal written contracts. Typical for the main business relationships was also that they are not based on the existence of the key persons only; the relationship would remain even if the key people left the business. The quality of these relationships was satisfactory in both chains and across all the stakeholder groups, though the downstream processors and the retailers had a slightly more positive view on their main business partners than the farmers and the upstream processors. The businesses operating in the pig meat chain seemed also to be more dependent on their main business relations when compared to the businesses in the rye chain. Although the communication means were rather similar in both chains (the phone being the most important), there was some variation between the chains concerning the communication frequency necessary to maintain the relationship with the main business partner. In short, the businesses in the pig meat chain seemed to appreciate more frequent communication with their main business partners when compared to the businesses in the rye chain. Personal meetings with the main business partners were quite rare in both chains. All the respondent groups were, however, fairly satisfied with the communication frequency and information quality between them and the main business partner. The business cultures could be argued to be rather hegemonic among the businesses both in the pig meat and rye chains. Avoidance of uncertainty, appreciation of long-term orientation and independence were considered important factors in the business cultures. Furthermore, trust, commitment and satisfaction in business partners were thought to be essential elements of business operations in all the respondent groups. In order to investigate which factors have an effect on the choice of a relationship type, several hypotheses were tested by using binary and multinomial logit analyses. According to these analyses it could be argued that avoidance of uncertainty and risk has a certain effect on the relationship type chosen, i.e. the willingness to avoid uncertainty increases the probability to choose stable relationships, like repeated market transactions and formal written contracts, but not necessary those, which require high financial commitment (like financial participation arrangements). The probability of engaging in financial participation arrangements seemed to increase with long-term orientation. The hypotheses concerning the sustainability of the economic relations were tested by using structural equation model (SEM). In the model, five variables were found to have a positive and statistically significant impact on the sustainable economic relationship construct. Ordered relative to their importance, those factors are: (i) communication quality, (ii) personal bonds, (iii) equal power distribution, (iv) local embeddedness and (v) competition.

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Tämän pro gradu-tutkielman tavoitteena oli kartoittaa voittoa tavoittelemattoman Slow Food-organisaation brandiin liitettyjä mielikuvia ja niitä tekijöitä, joilla brandin tavoitekuvaa tulisi jatkossa rakentaa. Koska nykyisin brandi ei ole enää pelkkien liikeyritysten yksityisomaisuutta, tutkimuksen teoreettinen asemointi perustui yhtäältä organisaation tunnettuuden kasvattamiseen brandin rakentamisen avulla ja toisaalta voittoa tavoittelemattoman toimintaympäristön erityispiirteiden näkökulmaan. Case-osion avulla haluttiin tarkastella globalisaation ja elintarviketalouden keskittymiselle vaihtoehtoisen, paikallisuuteen perustuvan ruokajärjestelmän vaikutuksia, mahdollisuuksia ja haasteita. Tutkimuksen empiirinen osuus muodostui laadullisesta tapaustutkimuksesta, jonka kohteena oli Slow Food-organisaatio. Tutkimus suoritettiin haastattelemalla kahtatoista Slow Food-organisaation sidosryhmien edustajaa Italian Piemontessa henkilökohtaisin haastatteluin, joiden pohjana oli brandi identiteetin elementeistä luodut kaksi teemaa: mielleyhtymiin ja arvoväittämään liittyvät tekijät. Aineiston analysoinnissa käytettiin teemoittelua ja sisällönanalyysia. Tutkimuksen lähestymistapa oli abduktiivinen. Tulosten mukaan Slow Food-brandi identifioituu sidosryhmilleen ensisijaisesti luotettavan ruoan kautta, johon katsottiin kuuluvan aidot, puhtaat raaka-aineet ja paikallisesti tuotetun ja jalostamattoman ruoan hyvä jäljitettävyys. Myös tiettyyn paikkaan ja arvoihin sidottujen kokemusten ja odostusten täyttymisen kautta saatu sosiaalinen ja kulttuurinen jatkuvuus nimettiin brandin vahvuudeksi. Lisäksi vastuullisen tuottamisen ja kuluttamisen sekä aitojen makujen ja laadukkaan ruokavalion edistäminen korostuivat jonkin verran vastauksissa. Näillä perusvahvuuksilla toivottiin brandin identiteettiä rakennettavan myös tulevaisuudessa. Haastateltavien mielestä Slow Food-organisaatio erilaistaa itsensä muista ensisijaisesti lupaamalla yksilölle korkealuokkaisia, aitoja tuotteita ja palveluja, joilla on henkilökohtaisten hyötyjen lisäksi positiivisia seuraamuksia myös oman alueen työllisyyden ja talouden kehitykseen. Organisaation tulisi myös jatkossa luoda uskottavuutta toimintaansa eritoten sen kautta, että brandi lunastaa lupauksensa laadusta ja aitoudesta. Toisaalta erottautuakseen muista lähi- ja luomuruokabrandeista Slow Food-brandin arvoväittämässä tulisi tulevaisuudessa selkeämmin korostua myös toiminnan voittoa tavoittelemattomuus ja brandiin liittyvä elämyksellisyys. Sidosryhmien kiinnostusta ja brandin lupauksen tehoa alentaviksi tekijöiksi nimettiin yleinen ruoan arvostuksen väheneminen sekä Slow Food-tuotteiden ja -palvelujen korkea hinta, huono saatavuus ja näkyvyys. Keskeisimpinä ratkaisuina pidettiin kuluttajien informatiivisen tiedon lisäämisen ohella pientuottajien verkostoitumista ja uusia yhteistyön muotoja kuten tuottajien yhteisiä jakeluketjuja ja paikallismyymälöitä. Näiden lisäksi brandin tunnistettavuuden parantaminen ja aktiivisempi tarjonta kyltityksin, tuotteiden pysyvän läsnäolon ja vähittäiskaupan mukaantulon kautta sekä eräät muut markkinoinnin osa-alueet kuten sosiaalinen media, Internet ja kansainväliset ruoka-alan tapahtumat nimettiin brandin lupausta kirkastaviksi elementeiksi. Pientuotannon lisääminen verotuksen kohdentumisen muutoksilla nähtiin keinoksi pudottaa paikallisen ruoan hintaa.Toisaalta korkeaa hintaa perusteltiin laadukkaaseen imagoon liittyvien argumenttien lisäksi luonnollisen kysynnän kasvulla, jota arveltiin saatavan tulevaisuudessa suurista ikäluokista, yhä kasvavasta koulutus- ja tulotasosta sekä valveutuneemmista kuluttajista.

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The reported incidence of human campylobacteriosis in Finland is higher than in most other European countries. A high annual percentage of sporadic infections is of foreign origin, although a notable proportion of summer infections is domestically acquired. While chickens appear to be a major source of campylobacters for humans in most countries, the prevalence of campylobacters is very low in chicken slaughter batches in Finland. Data on other potential animal reservoirs of human pathogenic campylobacters in Finland are scarce. Consequently, this study aimed to investigate the status of Finnish cattle as a potential source of thermophilic Campylobacter spp. and antibiotic-resistant Campylobacter jejuni for human sporadic campylobacter infections of domestic origin. A survey of the prevalence of thermophilic Campylobacter spp. in Finnish cattle studied bovine rectal faecal samples (n=952) and carcass surface samples (n=948) from twelve Finnish slaughterhouses from January to December 2003. The total prevalence of Campylobacter spp. in faecal samples was 31.1%, and in carcass samples 3.5%. Campylobacter jejuni, the most common species, was present in 19.5% of faecal samples and in 3.1% of carcasses. In addition to thermophilic Campylobacter spp., C. hyointestinalis ssp. hyointestinalis was present in bovine samples. The prevalence of campylobacters was higher among beef cattle than among dairy cattle. Using the enrichment method, the number of positive faecal samples was 7.5 times higher than that obtained by direct plating. The predominant serotypes of faecal C. jejuni, determined by serotyping with a set of 25 commercial antisera for heat-stable antigens (Penner), were Pen2 and Pen4-complex, which covered 52% of the samples. Genotyping with pulsed-field gel electrophoresis (PFGE) using SmaI restriction yielded a high diversity of C. jejuni subtypes in cattle. Determining the minimum inhibitory concentrations of ampicillin, enrofloxacin, erythromycin, gentamicin, nalidixic acid, and oxytetracycline among bovine C. jejuni isolates using a commercial broth microdilution method yielded 9% of isolates resistant to at least one of the antimicrobials examined. No multiresistant isolates were found among the bovine C. jejuni strains. The study of the shedding patterns of Campylobacter spp. among three Finnish dairy cattle herds included the examination of fresh faecal samples and tank milk samples taken five times, as well as samples from drinking troughs taken once during the one-year study. The semiquantitative enrichment method detected C. jejuni in 169 of the 340 faecal samples, mostly at low levels. In addition, C. jejuni was present in one drinking trough sample. The prevalence between herds and sampling occasions varied widely. PFGE, using SmaI as restriction enzyme, identified only a few subtypes in each herd. In two 2 of the herds, two subtypes persisted throughout the sampling. Individual animals presented various shedding patterns during the study. Comparison of C. jejuni isolates from humans, chickens and cattle included the design of primers for four new genetic markers selected from completely sequenced C. jejuni genomes 81-176, RM1221 and NCTC 11168, and the PCR examination of domestic human isolates from southern Finland in 1996, 2002 and 2003 (n=309), chicken isolates from 2003, 2006 and 2007 (n=205), and bovine isolates from 2003 (n=131). The results revealed that bovine isolates differed significantly from human and chicken isolates. In particular, the - glutamyl transpeptidase gene was uncommon among bovine isolates. The PFGE genotyping of C. jejuni isolates, using SmaI and KpnI restriction enzymes, included a geographically representative collection of isolates from domestic sporadic human infections, chicken slaughter batches, and cattle faeces and carcasses during the seasonal peak of campylobacteriosis in the summer of 2003. The study determined that 55.4% of human isolates were indistinguishable from those of chickens and cattle. Temporal association between isolates from humans and chickens was possible in 31.4% of human infections. Approximately 19% of the human infections may have been associated with cattle. However, isolates from bovine carcasses and human cases represented different PFGE subtypes. In conclusion, this study suggests that Finnish cattle is a notable reservoir of C. jejuni, the most important Campylobacter sp. in human enteric infections. Although the concentration of these organisms in bovine faeces appeared to be low, excretion can be persistent. The genetic diversity and presence or absence of marker genes support previous suggestions of host-adapted C. jejuni strains, and may indicate variations in virulence between strains from different hosts. In addition to chickens, Finnish cattle appeared to be an important reservoir and possible source of C. jejuni in domestic sporadic human infections. However, sources of campylobacters may differ between rural and urban areas in Finland, and in general, the transmission of C. jejuni of bovine origin probably occurs via other routes than food.

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Herbivorous insects, their host plants and natural enemies form the largest and most species-rich communities on earth. But what forces structure such communities? Do they represent random collections of species, or are they assembled by given rules? To address these questions, food webs offer excellent tools. As a result of their versatile information content, such webs have become the focus of intensive research over the last few decades. In this thesis, I study herbivore-parasitoid food webs from a new perspective: I construct multiple, quantitative food webs in a spatially explicit setting, at two different scales. Focusing on food webs consisting of specialist herbivores and their natural enemies on the pedunculate oak, Quercus robur, I examine consistency in food web structure across space and time, and how landscape context affects this structure. As an important methodological development, I use DNA barcoding to resolve potential cryptic species in the food webs, and to examine their effect on food web structure. I find that DNA barcoding changes our perception of species identity for as many as a third of the individuals, by reducing misidentifications and by resolving several cryptic species. In terms of the variation detected in food web structure, I find surprising consistency in both space and time. From a spatial perspective, landscape context leaves no detectable imprint on food web structure, while species richness declines significantly with decreasing connectivity. From a temporal perspective, food web structure remains predictable from year to year, despite considerable species turnover in local communities. The rate of such turnover varies between guilds and species within guilds. The factors best explaining these observations are abundant and common species, which have a quantitatively dominant imprint on overall structure, and suffer the lowest turnover. By contrast, rare species with little impact on food web structure exhibit the highest turnover rates. These patterns reveal important limitations of modern metrics of quantitative food web structure. While they accurately describe the overall topology of the web and its most significant interactions, they are disproportionately affected by species with given traits, and insensitive to the specific identity of species. As rare species have been shown to be important for food web stability, metrics depicting quantitative food web structure should then not be used as the sole descriptors of communities in a changing world. To detect and resolve the versatile imprint of global environmental change, one should rather use these metrics as one tool among several.

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The modern food system and sustainable development form a conceptual combination that suggests sustainability deficits in environmental impacts and nutritional status of western populations. This study explores actors orientations towards sustainability by probing into social dynamics for sustainability within primary production and public consumption. If actors within these two worlds were to express converging orientations for sustainability, the system dynamics of the market would enable more sustainable growth in terms of production dictated by consumption. The study is based on a constructivist research approach with qualitative text analyses. The findings were validated by internal and external food system actors and are suggested to represent current social dynamics within Finnish food system. The key findings included primary producers social skilfulness, which enabled networking with other actors in very different paths of life, learning in order to promote one s trade, and trusting reflectively in partners in order to expand business. These activities extended the supply chain in a spiral fashion by horizontal and vertical forward integration, until large retailers were met for negotiations on a more equal basis. This mode of chain level coordination, typically building around the core of social and partnership relations, was coined as a socially overlaid network, and seen as sustainable coordination mode for endogenous growth. The caterers exhibited more or less committed professional identity for sustainability within their reach. The facilitating approaches for professional identities dealt successfully with local and organic food in addition to domestic food, and also imported food. The co-operation with supply chains created innovative solutions and savings for the business parties to be shared. There were also more complicated identities as juggling, critical and delimited approaches for sustainability, with less productive efforts due to restrictions such as absence of organisational sustainability strategy, weak presence of local and organic suppliers, limited understanding about sustainability and no organisational resources for informed choices for sustainability. The convergence between producers and caterers existed to an extent allowing suggestion that increased clarity about sustainable consumption and production by actors could be constructed using advanced tools. The study looks for introduction of more profound environmental and socio-economic knowledge through participatory research with supply chain actors. Learning in the workplace about food system reality in terms of supply chain co-operation may prove to be a change engine that leads to advanced network operations and a more sustainable food system.

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Abstract The modern food system and sustainable development form a conceptual combination that suggests sustainability deficits in the ways we deal with food consumption and production - in terms of economic relations, environmental impacts and nutritional status of western population. This study explores actors’ orientations towards sustainability by taking into account actors’ embedded positions within structures of the food system, actors’ economic relations and views about sustainability as well as their possibilities for progressive activities. The study looks particularly at social dynamics for sustainability within primary production and public consumption. If actors within these two worlds were to express converging orientations for sustainability, the system dynamics of the market would enable more sustainable growth in terms of production dictated by consumption. The study is based on a constructivist research approach with qualitative text analyses. The data consisted of three text corpora, the ‘local food corpus’, the ‘catering corpus’ and the ‘mixed corpus’. The local food actors were interviewed about their economic exchange relations. The caterers’ interviews dealt with their professional identity for sustainability. Finally, the mixed corpus assembled a dialogue as a participatory research approach, which was applied in order to enable researcher and caterer learning about the use of organic milk in public catering. The data were analysed for theoretically conceptualised relations, expressing behavioural patterns in actors’ everyday work as interpreted by the researcher. The findings were corroborated by the internal and external communities of food system actors. The interpretations have some validity, although they only present abstractions of everyday life and its rich, even opaque, fabric of meanings and aims. The key findings included primary producers’ social skilfulness, which enabled networking with other actors in very different paths of life, learning in order to promote one’s trade, and trusting reflectively in partners in order to extend business. These activities expanded the supply chain in a spiral fashion by horizontal and vertical forward integration, until large retailers were met for negotiations on a more equal or ‘other regarding’ basis. This kind of chain level coordination, typically building around the core of social and partnership relations, was coined as a socially overlaid network. It supported market access of local farmers, rooted in their farms, who were able to draw on local capital and labour in promotion of competitive business; the growth was endogenous. These kinds of chains – one conventional and one organic – were different from the strategic chain, which was more profit based and while highly competitive, presented exogenous growth as it depended on imported capital and local employees. However, the strategic chain offered learning opportunities and support for the local economy. The caterers exhibited more or less committed professional identity for sustainability within their reach. The facilitating and balanced approaches for professional identities dealt successfully with local and organic food in addition to domestic food, and also imported food. The co-operation with supply chains created innovative solutions and savings for the business parties to be shared. The rule-abiding approach for sustainability only made choices among organic supply chains without extending into co-operation with actors. There were also more complicated and troubled identities as juggling, critical and delimited approaches for sustainability, with less productive efforts due to restrictions such as absence of organisational sustainability strategy, weak presence of local and organic suppliers, limited understanding about sustainability and no organisational resources to develop changes towards a sustainable food system. Learning in the workplace about food system reality in terms of supply chain co-operation may prove to be a change engine that leads to advanced network operations and a more sustainable food system. The convergence between primary producers and caterers existed to an extent allowing suggestion that increased clarity about sustainable consumption and production by actors could be approached using advanced tools. The study looks for introduction of more profound environmental and socio-economic knowledge through participatory research with supply chain actors in order to promote more sustainable food systems. Summary of original publications and the authors’ contribution I Mikkola, M. & Seppänen, L. 2006. Farmers’ new participation in food chains: making horizontal and vertical progress by networking. In: Langeveld, H. & Röling N. (Eds.). Changing European farming systems for a better future. New visions for rural areas. Wageningen, The Netherlands. Wageningen Academic Publishers: 267–271. II Mikkola, M. 2008. Coordinative structures and development of food supply chains. British Food Journal 110 (2): 189–205. III Mikkola, M. 2009. Shaping professional identity for sustainability. Evidence in Finnish public catering. Appetite 53 (1): 56–65. IV Mikkola, M. 2009. Catering for sustainability: building a dialogue on organic milk. Agronomy Research 7 (Special issue 2): 668–676. Minna Mikkola has been responsible for developing the generic research frame, particular research questions, the planning and collection of the data, their qualitative analysis and writing the articles I, II, III and IV. Dr Laura Seppänen has contributed to the development of the generic research frame and article I by introducing the author to the basic concepts of economic sociology and by supporting the writing of article II with her critical comments. Articles are printed with permission from the publishers.

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Enzymes offer many advantages in industrial processes, such as high specificity, mild treatment conditions and low energy requirements. Therefore, the industry has exploited them in many sectors including food processing. Enzymes can modify food properties by acting on small molecules or on polymers such as carbohydrates or proteins. Crosslinking enzymes such as tyrosinases and sulfhydryl oxidases catalyse the formation of novel covalent bonds between specific residues in proteins and/or peptides, thus forming or modifying the protein network of food. In this study, novel secreted fungal proteins with sequence features typical of tyrosinases and sulfhydryl oxidases were iden-tified through a genome mining study. Representatives of both of these enzyme families were selected for heterologous produc-tion in the filamentous fungus Trichoderma reesei and biochemical characterisation. Firstly, a novel family of putative tyrosinases carrying a shorter sequence than the previously characterised tyrosinases was discovered. These proteins lacked the whole linker and C-terminal domain that possibly play a role in cofactor incorporation, folding or protein activity. One of these proteins, AoCO4 from Aspergillus oryzae, was produced in T. reesei with a production level of about 1.5 g/l. The enzyme AoCO4 was correctly folded and bound the copper cofactors with a type-3 copper centre. However, the enzyme had only a low level of activity with the phenolic substrates tested. Highest activity was obtained with 4-tert-butylcatechol. Since tyrosine was not a substrate for AoCO4, the enzyme was classified as catechol oxidase. Secondly, the genome analysis for secreted proteins with sequence features typical of flavin-dependent sulfhydryl oxidases pinpointed two previously uncharacterised proteins AoSOX1 and AoSOX2 from A. oryzae. These two novel sulfhydryl oxidases were produced in T. reesei with production levels of 70 and 180 mg/l, respectively, in shake flask cultivations. AoSOX1 and AoSOX2 were FAD-dependent enzymes with a dimeric tertiary structure and they both showed activity on small sulfhydryl compounds such as glutathione and dithiothreitol, and were drastically inhibited by zinc sulphate. AoSOX2 showed good stabil-ity to thermal and chemical denaturation, being superior to AoSOX1 in this respect. Thirdly, the suitability of AoSOX1 as a possible baking improver was elucidated. The effect of AoSOX1, alone and in combi-nation with the widely used improver ascorbic acid was tested on yeasted wheat dough, both fresh and frozen, and on fresh water-flour dough. In all cases, AoSOX1 had no effect on the fermentation properties of fresh yeasted dough. AoSOX1 nega-tively affected the fermentation properties of frozen doughs and accelerated the damaging effects of the frozen storage, i.e. giving a softer dough with poorer gas retention abilities than the control. In combination with ascorbic acid, AoSOX1 gave harder doughs. In accordance, rheological studies in yeast-free dough showed that the presence of only AoSOX1 resulted in weaker and more extensible dough whereas a dough with opposite properties was obtained if ascorbic acid was also used. Doughs containing ascorbic acid and increasing amounts of AoSOX1 were harder in a dose-dependent manner. Sulfhydryl oxidase AoSOX1 had an enhancing effect on the dough hardening mechanism of ascorbic acid. This was ascribed mainly to the produc-tion of hydrogen peroxide in the SOX reaction which is able to convert the ascorbic acid to the actual improver dehydroascorbic acid. In addition, AoSOX1 could possibly oxidise the free glutathione in the dough and thus prevent the loss of dough strength caused by the spontaneous reduction of the disulfide bonds constituting the dough protein network. Sulfhydryl oxidase AoSOX1 is therefore able to enhance the action of ascorbic acid in wheat dough and could potentially be applied in wheat dough baking.

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This research investigates the impacts of agricultural market liberalization on food security in developing countries and it evaluates the supply perspective of food security. This research theme is applied on the agricultural sector in Kenya and in Zambia by studying the role policies played in the maize sub-sector. An evaluation of selected policies introduced at the beginning of the 1980s is made, as well as an assessment of whether those policies influenced maize output. A theoretical model of agricultural production is then formulated to reflect cereal production in a developing country setting. This study begins with a review of the general framework and the aims of the structural adjustment programs and proceeds to their application in the maize sector in Kenya and Zambia. A literature review of the supply and demand synthesis of food security is presented with examples from various developing countries. Contrary to previous studies on food security, this study assesses two countries with divergent economic orientations. Agricultural sector response to economic and institutional policies in different settings is also evaluated. Finally, a dynamic time series econometric model is applied to assess the effects of policy on maize output. The empirical findings suggest a weak policy influence on maize output, but the precipitation and acreage variables stand out as core determinants of maize output. The policy dimension of acreage and how markets influence it is not discussed at length in this study. Due to weak land rights and tenure structures in these countries, the direct impact of policy change on land markets cannot be precisely measured. Recurring government intervention during the structural policy implementation period impeded efficient functioning of input and output markets, particularly in Zambia. Input and output prices of maize and fertilizer responded more strongly in Kenya than in Zambia, where the state often ceded to public pressure by revoking pertinent policy measures. These policy interpretations are based on the response of policy variables which are more responsive in Kenya than in Zambia. According the obtained regression results, agricultural markets in general, and the maize sub-sector in particular, responded more positively to implemented policies in Kenya, than in Zambia, which supported a more socialist economic system. It is observed in these results that in order for policies to be effective, sector and regional dimensions need to be considered. The regional and sector dimensions were not taken into account in the formulation and implementation of structural adjustment policies in the 1980s. It can be noted that countries with vibrant economic structures and institutions fared better than those which had a firm, socially founded system.

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C. jejuni constitutes the majority of Campylobacter strains isolated from patients in Finland, and C. coli strains are also reported. To improve the species identification, a combination of phenotype- and genotype-based methods was applied. Standardising the cell suspension turbidity in the hippurate hydrolysis test enabled the reliable identification of hippurate-positive Campylobacter strains as C. jejuni. The detection of species-specific genes by PCR showed that about 30% of the hippurate-negative strains were C. jejuni. Three typing methods, serotyping, PCR-RFLP analysis of LOS biosynthesis genes and pulsed-field gel electrophoresis (PFGE) were evaluated as epidemiological typing tools for C. jejuni. The high number of non-typeable strains lowered the discriminatory ability of serotyping. PCR-RFLP typing offered high discrimination for both serotypeable and non-typeable strains, but the correlation between serotypes and RFLP-types was not high enough to enable its use for molecular serotyping of non-typeable strains. PFGE was a highly discriminative typing method. Although the use of two restriction enzymes generally increases the discriminatory ability, KpnI alone offered almost as high discrimination as the use of SmaI and KpnI. The characteristic seasonal distribution of Campylobacter infections with a peak in summer and low incidence in winter was mainly due to domestically acquired infections. Of the C. jejuni strains, 41% were of domestic origin compared to only 17% of the C. coli strains. Serotypes Pen 12, Pen 6,7 and Pen 27 were significantly associated with domestic C. jejuni infections, Pen 1,44, Pen 3 and Pen 37 with travel-related infections. Pen 2 and Pen 4-complex were common both in domestic and travel-related infections. Serotype Pen 2 was less common among patients 60 years or older than in younger patients, more prevalent in Western Finland than in other parts of the country and more prevalent than other serotypes in winter. The source of Pen 2 infections may be related to cattle, since Pen 2 is the most common serotype in isolates from Finnish cattle. PFGE subtypes among isolates from patients and chickens during the summer 2003 and from cattle during the whole year were compared. The analysis of indistinguishable SmaI/KpnI subtypes suggested that up to 31% of the human infections may have been mediated by chickens and 19% by cattle. Human strains isolated during two one-year sampling periods were studied by PFGE. Of the domestic strains, 69% belonged to SmaI subtypes found during both sampling periods. Four SmaI subtypes accounted for 45% of the domestic strains, further typing of these subtypes by KpnI revealed six temporally persistent SmaI/KpnI subtypes. They were only occasionally identified in travel-related strains, and therefore, can be considered to be national subtypes. Each subtype was associated with a serotype: Pen 2, Pen 12, Pen 27, Pen 4-complex, Pen 41, and Pen 57. Five of these subtypes were identified in cattle (S5/K27, S7/K1, S7/K2, S7/K5 and S64/K19), and two in chickens (S7/K1 and S64/K19) with a temporal association with human infections in 2003. Cattle are more likely potential sources of these persistent subtypes, since long-term excretion of Campylobacter strains by cattle has been reported.

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A typical feature of type II restriction endonucleases (REases) is their obligate sequence specificity and requirement for Mg2+ during catalysis. R.KpnI is an exception. Unlike most other type II REases, the active site of this enzyme can accommodate Mg2+, Mn2+, Ca2+, or Zn2+ and cleave DNA. The enzyme belongs to the HNH superfamily of nucleases and is characterized by the presence of a beta beta alpha-Me finger motif. Residues D148, H149, and Q175 together form the HNH active site and are essential for Mg2+ binding and catalysis. The unique ability of the enzyme to cleave DNA in the presence of different metal ions is exploited to generate mutants that are specific to one particular metal ion. We describe the generation of a Mn2+-dependent sequence specific endonuclease, defective in DNA cleavage with Mg2+ and other divalent metal ions. In the engineered mutant, only Mn2+ is selectively bound at the active site, imparting Mn2+-mediated cleavage. The mutant is impaired in concerted double-stranded DNA cleavage, leading to accumulation of nicked intermediates. The nicking activity of the mutant enzyme is further enhanced by altered reaction conditions. The active site fluidity of R Eases allowing flexible accommodation of catalytic cofactors thus forms a basis for engineering selective metal ion-dependent REase additionally possessing nicking activity.

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Campylobacter, mainly Campylobacter jejuni and C. coli, are worldwide recognized as a major cause of bacterial food-borne gastroenteritis (World Health Organization 2010). Epidemiological studies have shown handling or eating of poultry to be significant risk factors for human infections. Campylobacter contamination can occur at all stages of a poultry meat production cycle. In summer 1999, every broiler flock from all three major Finnish poultry slaughterhouses was studied during a five month period. Caecal samples were taken in the slaughterhouses from five birds per flock. A total of 1 132 broiler flocks were tested and 33 (2.9%) of those were Campylobacter-positive. Thirty-one isolates were identified as C. jejuni and two isolates were C. coli. The isolates were serotyped for heat-stable antigens (HS) and genotyped by pulsed-field gel electrophoresis (PFGE). The most common serotypes found were HS 6,7, 12 and 4-complex. Using a combination of SmaI and KpnI patterns, 18 different PFGE types were identified. Thirty-five Finnish C. jejuni strains with five SmaI/SacII PFGE types selected among human and chicken isolates from 1997 and 1998 were used for comparison of their PFGE patterns, amplified fragment length polymorphism (AFLP) patterns, HaeIII ribotypes, and HS serotypes. The discriminatory power of PFGE, AFLP and ribotyping with HaeIII were shown to be at the same level for this selected set of strains, and these methods assigned the strains into the same groups. The PFGE and AFLP patterns within a genotype were highly similar, indicating genetic relatedness. An HS serotype was distributed among different genotypes, and different serotypes were identified within one genotype. From one turkey parent flock, the hatchery, six different commercial turkey farms (together 12 flocks) and from 11 stages at the slaughterhouse a total of 456 samples were collected during one and the half year. For the detection of Campylobacter both conventional culture and a PCR method were used. No Campylobacter were detected in either of the samples from the turkey parent flock or from the hatchery samples using the culture method. Instead PCR detected DNA of Campylobacter in five faecal samples from the turkey parent flock and in one fluff and an eggshell sample. Six out of 12 commercial turkey flocks were found negative at the farm level but only two of those were negative at slaughter. Campylobacter-positive samples within the flock at slaughter were detected between 0% and 94%, with evisceration and chilling water being the most critical stages for contamination. All of a total of 121 Campylobacter isolates were shown to be C. jejuni using a multiplex PCR assay. PFGE analysis of all isolates with KpnI restriction enzyme resulted in 11 PFGE types (I-XI) and flaA-SVR typing yielded nine flaA-SVR alleles. Three Campylobacter-positive turkey flocks were colonized by a limited number of Campylobacter genotypes both at the farm and slaughter level.In conclusion, in our first study in 1999 a low prevalence of Campylobacter in Finnish broiler flocks was detected and it has remained at a low level during the study period until the present. In the turkey meat production, we found that flocks which were negative at the farm became contaminated with Campylobacter at the slaughter process. These results suggest that proper and efficient cleaning and disinfection of slaughter and processing premises are needed to avoid cross-contamination. Prevention of colonization at the farm by a high level of biosecurity control and hygiene may be one of the most efficient ways to reduce the amount of Campylobacter-positive poultry meat in Finland. In Finland, with a persistent low level of Campylobacter-positive flocks, it could be speculated that the use of logistic slaughtering, according to Campylobacter status at farm, might have be advantageous in reducing Campylobacter contamination of retail poultry products. However, the significance of the domestic poultry meat for human campylobacteriosis in Finland should be evaluated.