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(2018)Many food products such as butter, salad dressings and ice-cream consist of water-in-oil (W/O) or oil-in-water (O/W) emulsions. Emulsions are thermodynamically unstable and this is the reason why food industry uses different kinds of emulsifiers and stabilizers which extend the shelf-life of the products and also improves their quality. The consumers’ interest towards plan-based and sustainable ingredients has increased, but at the moment the number of Finnish plant-based stabilizers is limited. Forest industry is also under pressure to find new use for its by-products.. Some studies on the glucuronoxylan and galactoglucomannan extracted from spruce and birch saw meal have been made and the results have been promising. Xylan has been extracted by different methods and from birch sawdust the yield has been approximately 50 wt%. The use of birch GX in food products has not yet been authorized, but the food industry is already using some of the byproducts of woodworking industry such as xylitol. The aim of this study was to find the suitable mixture ratio of oil, water and birch glucuronoxylan in emulsions as well as the factors affecting the physical state of the emulsions. The results of this study can be used to support the findings of other studies so that domestic plant based emulsion stabilizers can be used in the food-industry in the future. In this study seven different emulsions were produced by varying the ratio of oil and glucuronoxylan. By studying the physical properties of the freshly prepared emulsions together with the varying storage conditions (+4 °C, +21 °C and +40 °C) the study aimed to find the optimal mixture ratio. The droplet size of dispersed phase was studied by using static light scattering and the possible flocculation was viewed by optical microscopy. The height of the creamed phase and the turbidity/ other changes in appearance were visually investigated by photographing the samples. A sample of emulsion was taken apart and centrifuged to find out the amount of xylan on the oil droplet interface and in the continuous phase. In addition, the monosaccharide composition of xylan on oil droplet interface and continuous phase were determined by gas chromatography mass spectrometry (GC-MS). All the seven emulsions investigated were polydispersions according to the droplet size distribution. There were two peaks on almost every droplet size distributions since the first measuring. The droplet size distributions were stable for the whole 67 days investigation period when the emulsions were stored in +4 °C temperature excluding two emulsions. In +21 °C and +40 °C temperatures the droplet size of all the investigated emulsion grew. The greatest part of the carbohydrates was in the continuous phase of emulsions. The size difference between the polysaccharides from the surface of the oil droplets and the continuous phase was not big. About 80 % of the monosaccharides in the emulsions was xylose. According to the findings of this study, there was more methyl glucuronic acid, which is a component of xylan, in the water than in the interfacial oil phase of the emulsions (0.65 – 5.7 μg/g).
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(2019)Gluteeniton kauraleivonta on teknologisesti haastavaa, sillä viskoelastisen gluteeniverkoston puuttuessa kaurataikinoita on hankalaa työstää ja kauraleivät jäävät usein tiiviiksi, kosteiksi ja tahmeiksi. Hyväksyttävän rakenteen aikaansaanti on vaikeaa ja gluteenittomille leiville on tyypillistä, että ne vanhenevat nopeasti. Leivän vanhenemiseen johtavina tekijöinä pidetään tärkkelyksen uudelleenkiteytymistä ja veden liikkumista leivässä säilytyksen aikana. Tutkimuksen tavoitteena oli parantaa gluteenittoman kauraleivän säilyvyyttä käyttämällä taikinassa esiliisteröityä tärkkelystä. Tutkimuksen hypoteesina oli, että velliksi esiliisteröidyn kaurajauhon käytöllä vesi saadaan sidottua tiukemmin tärkkelysgeeliin, jolloin säilytyksen aikana tapahtuva veden liikkuminen leivässä hidastuu. Kun rakennetta pehmentävä vesi puristuu hitaammin ulos tärkkelysgeelistä ja liisteröityneisiin, amorfisiin tärkkelysalueisiin on sitoutunut enemmän vettä, on leivän rakennetta kovettavien tärkkelyskiteiden muodostuminen hitaampaa. Lisäksi tutkimuksessa vertailtiin kauravellin hapatusta mikrobiologisella ja kemiallisella menetelmällä. Mikrobiologisen hapatuksen aikana jauhopartikkelit ehtivät vettyä ja liueta edelleen, ja tällä oletettiin olevan rakennetta pehmentävä vaikutus. Tutkimuksen kokeellisessa osassa kauraleipien rakenteen kovettumista tutkittiin kaksivaiheisella puristustestillä aineenkoestuslaitteella ja tärkkelyksen uudelleenkiteytymistä seurattiin DSC-kalorimetrillä. Taikinoiden ominaisuuksia havainnollistettiin erilaisin geelitestein. Tutkimuksessa havaittiin, että esiliisteröity kauravelli lisäsi kaurataikinan kaasunpidätyskykyä ja kasvatti kauraleivän ominaistilavuutta. Kemiallisesti hapatettua velliä sisältäneessä kauraleivässä rakenteen kovettuminen oli hitainta ja leipä oli tilastollisesti pehmein kuudenteen säilytyspäivään asti. Mikrobiologisesti hapatetun vellin käyttö taas nopeutti kauraleivän rakenteen vanhenemista. Esiliisteröidyn vellin käyttö pehmensi gluteenittoman kauraleivän rakennetta liisteröimällä enemmän tärkkelystä amorfiseen muotoon ja hidastamalla veden liikkumista leivässä säilytyksen aikana. Kauravellin kemiallinen hapatus pehmensi kauraleivän rakennetta edelleen, ja rakenne oli vellitöntä leipää pehmeämpi vielä kuudentena säilytyspäivänä. Tutkimuksessa onnistuttiin pidentämään gluteenittoman kauraleivän pehmeää aikaa käyttämällä taikinassa kemiallisesti hapatettua, esiliisteröityä velliä.
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(2021)Tutkimuksen tarkoituksena oli kartoittaa optimaalinen hydrokolloidiyhdistelmä, joka parantaa gluteenittoman leivän rakennetta ja tuoreena säilymistä. Hypoteesina oli, että löytyisi tietty kahden hydrokolloidin yhdistelmä koesuunnitelmaa käyttämällä. Tutkimuksessa käytettiin kolmea eri hydrokolloidia ja niiden määrät vaihtelivat kolmella eri tasolla. Hydrokolloidien vesiliuosten reologisia ominaisuuksia tutkittiin viskositeetti- ja oskillaatiomittauksilla. Leivistä mitattiin tilavuus, rakenne ja rakenteen säilyminen seitsemän vuorokauden säilytyksessä ja raskista mitattiin pH ja happoluku. Leivistä tehtiin myös aistinvarainen asiantuntija-arviointi. Raskien pH-arvojen keskiarvo oli 4,49 ±0,01 ja happoluvun keskiarvo 12,9 ±0,2. Hydrokolloidien vesiliuosseosten, GM + MNS1 ja GM + MNS2, viskositeettien mittauksissa virtauskäyrissä ei ollut eroa mutta GM:n (galaktomannaanista muodostunut kasvikumi, joka on peräisin palkokasvista) viskositeetti oli selvästi matalampi kuin seosten. Oskillaatiomittauksessa GM:n huomattiin myös erottuvan seoksista huomattavan paljon pienemmällä viskositeetilla sekä varasto- ja häviömoduulilla. GM muodostaa yksin ollessaan heikon geelirakenteen, mutta seoksilla on vahvempi geelirakenne. Modde-ohjelmiston vastepintaohjelman avulla saaduista tuloksista voitiin nähdä vain kimmoisuuden ja joustavuuden mallintuvan yhden päivän säilytyksen jälkeen. Tehtyjen analyysien perusteella päivä leivonnan jälkeen modifioitu neutraali selluloosa 1 (MNS1) ja modifioitu neutraali selluloosa 2 (MNS2) paransivat leivän joustavuutta. MNS2 lisäsi myös leipien kimmoisuutta, kun taas MNS1:llä ei ollut vaikutusta ja GM pienensi leipien kimmoisuutta. Myös seitsemännen säilytyspäivän jälkeen MNS1 piti leivän rakennetta joustavampana muihin saman ikäisiin leipiin verrattuna. Käytetyillä hydrokolloideilla ei ollut tilastollista eroa leivän kovuudessa, pureskeltavuudessa eikä murtumisherkkyydessä. Selkeitä eroja leivissä näkyi aistinvaraisesti arvioituna vain huokosjakaumassa. Huokosjakaumalta epätasaisimpia olivat leivät, joissa oli käytetty MNS1 tai MNS2 tasolla 3. Leipien säilönnän aikana oli kuitenkin huomattavissa selkeää kuivumista ja kovettumista. Leivonnasta seitsemännen päivän kohdalla lähes kaikki leivät olivat todella kovia ja sisus oli kuiva. Leipien maku oli myös heikentynyt aiempiin päiviin verrattuna. Tutkittujen hydrokolloidien vaikutusta leivän pehmeyteen ja nautittavuuteen ei voida todentaa tehtyjen tutkimusten perusteella, aistinvaraisesti arvioituna leivät eivät olleet selkeästi pehmeämpiä hydrokolloidilisäysten myötä.
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(2019)Gluten free baking differentiates from traditional wheat baking by the lack of structure stabilizing gluten network. The gluten in wheat flour mixed with water creates a visco-elastic dough that makes a good quality bread. In gluten free baking the structure of bread is improved with starches and hydrocolloids. Celiac decease, gluten yliherkkyys and wheat allergy are health related reasons to avoid gluten from wheat, barley and rye. There is no method for gluten free flours to predict the quality of the baked product like there is the farinograph water absorption method for wheat flour. These topics are discussed in the literature part of this work. The aim of this research was to look into the connection between gluten free dough consistency and the quality of baked bread. In the experimental part three different dough yields were selected: 190, 200 and 210. All dough yields were used with three different mixtures in consistency measurements: 100% buckwheat, 70 % buckwheat and 30 % tapioca and addition of 1 % psyllium to the latter mixture. Two different methods were tested (forward and backward extrusion) with Texture Analyser with all different dough variations. The principle in both methods are the same: the tests measure the compression force required for a piston to extrude the dough in a sample container. The doughs consistency and behavior were studied with farinograph to see if the results were consistent. Baking test was done with different dough yields with buckwheat, tapioca and psyllium mixture. Volume, baking loss and color were determined. Texture Profiler Analysis (TPA) was done 24h and 48h after baking. A sensory analysis conducted by professional panelists was done where porosity, softness, dryness, sponginess and intensity of buckwheat taste were assessed. Backward extrusion was found to be a better method for measuring consistency of the doughs. The results showed how the increasing water amount decreased consistency and same results were obtained with farinograph. Differences between breads were found with the sensory analysis as well. Intensity of flavor and porosity increased in bread with lower water amount whereas softness and moistness increased with increasing water amount when also the bread remained softer for longer. As a conclusion it can be stated that the backward extrusion is a suitable and reproducible method for buckwheat dough consistency measurements. Water absorption, bread structure and shelf life can be predicted and optimized based on consistency.
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(2021)The beneficial nutritional quality of oats and the recognition as a naturally gluten-free grain has increased its popularity. In the baking of wholemeal oat bread, the absence of gluten complicates the handling of the dough, and the oat cultivars differ in their baking quality a lot. For now, test baking is the only way to optimize whole oat baking. The aim of this study was to define how oat cultivars differ in their baking quality and how to adjust the dough yield for optimal baking result. The hypothesis was that oat varieties grown in different fields bake differently and by optimizing the dough consistency with dough yield, baking result can be improved. The work examined three oat cultivars and a total of five oat flour samples in the baking of palabread i.e. flat, yeast proofed bread. Moisture content, beta-glucan, and protein contents, pasting curves, particle sizes of flour and water binding were determined from the samples according to standard methods. All flour samples were baked first with dough yield of 215. The consistencies of doughs were measured with backward extrusion method by Texture Analyzer device. Based on the oat bread that proved to be the best in test baking, the optimal level of consistency was determined, to which dough yields were adjusted for the following baking tests. Breads baked with dough yields of 215 and breads obtained from optimized consistencies were compared sensorially and bread staling was measured by the hardness of the crumb for three days after baking. Oat cultivars differed in beta-glucan and protein contents. High beta-glucan and protein content of oat flour resulted in higher water-binding capacity and higher dough consistency. The low water-binding capacity of oat flour was associated with greater drying of the breads and faster aging. Moisture was bound better to the bread when the water-binding capacity of the oat was higher. The consistencies of the dough varieties of oat cultivars differed significantly with the same dough result, and the consistencies obtained from different flour samples of the same cultivars also differed from each other. There were no major sensory differences in the oat breads of the study, but breads baked from different oat flours differed in hardness and aging rates, even though the breads were baked with the same dough consistencies. The optimization of the consistency evened out the quality differences between the oat samples and improved the work-ability of the dough. The optimization was found to be successful in modifying handling of the dough and the structure of the baked bread in desired direction.
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(2015)The glycolytic potential of muscles is a representation of the energy reserve of a muscle and takes into account all compounds that are present in the muscle, which can be converted into lactic acid. A total of 219 breast muscle samples from five hybrids of male broiler chickens were used in this study. All from fast growing lines, they hybrids used are Ross 508, Cobb, Hubbard H1, Ross 308 and Rowan. The birds were reared under the same conditions, and slaughtered randomly at different ages. The pH, initial and ultimate, glycogen and lactic acid were assessed in all the samples. The glycolytic potential was calculated using results from the lactate and glycogen analysis. Older birds were associated with low glycogen concentrations. Wooden Breast muscles showed a very high significant difference with pHu (P<0.0001) and high significant difference with glycolytic potential (P = 0.0004). Affected breast muscles were associated with high pHu values and low glycolytic potential, where there was strong positive correlation between pHu and Wooden Breast presentation (P<0.0001, r = 0.414), and a weak negative correlation between the glycolytic potential and the presentation of Wooden Breast (P<0.0001, r = -0.292). Among the hybrids, Hubbard H1 recorded the highest glycolytic potential mean value of 117.22 while Ross 308 had the least mean value of 105.9 ± 5.6.
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(2014)Enterococci is a group of gram positive bacteria part of human intestinal flora. While generally harmless, several species of the group are known to cause severe infections in humans, including bloodstream infections leading to sepsis. Since Enterococci are naturally resistant to many antibiotics, the use of glycopeptides, considered a”last resort” drugs, is common in treatment of enterococcal infections. In recent years, however, the emergence of glycopeptide resistant Enterococci (GRE) has been an increasing concern for clinics and microbiology laboratories around the world, creating a need for fast and accurate screening tests differentiating the glycopeptide resistant Enterococcus strains from the non-resistant ones. In this study, a combined PCR and microarray hybridization based method for identification of the clinically most prevalent GRE was established as a part of commercial sepsis diagnostic test called Prove-it™ Sepsis. Already identifying the most common Enterococcus species (E.faecium and E.faecalis), the detection of glycopeptide resistance causing ligase genes vanA and vanB and species level identification of intrinsically glycopeptide resistant E.gallinarum and E.casseliflavus were added as part of the the test. Primers were designed for sequencing vanA and vanB genes and multiple strains, provided by a Finnish clinical laboratory Huslab, were sequenced. Sequence regions unique to these genes were identified according to sequence alignment data containing the sequenced gene regions and other relevant sequences found in public sequence databases. Based on these data, primers were designed for the amplification of the selected gene regions. For identification of the amplified gene regions, a set of hybridization probes were designed and printed on microarray. In addition, probes for identifying E.casseliflavus and E.gallinarum were designed based on sequence aligment data gathered from Mobidiag Ltd. private biobank. The identification of these species was based on topoisomerase encoding gyrB gene amplified by the Prove-it™ Sepsis broad range PCR. Several primers for the amplification of vanA and vanB genes were designed and one primer pair for each was selected to be integrated to the Prove-it™ Sepsis multiplex-PCR. Similarily, multiple hybridization probes were designed for detecting vanA, vanB, E.casseliflavus and E. gallinarum. Four probes for each target gene region were selected to be integrated to the commercial test. With this modified test, 12 pure culture samples of clinical origin were tested and the results were compared to the ones provided by the laboratory of clinical microbiology of Hôspital de bicêtre (Paris, France). Results provided by the modified PCR and microarray test were identical to the reference results in 11 out of 12 cases.
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(2019)Jääsalaattia (Lactuca sativa var. crispa L.) tuotetaan ympärivuotisesti kasvihuoneessa ja se on kuluttajien keskuudessa suosittu lehtivihannes. Jääsalaatti kerää monien muiden lehtivihannesten tapaan nitraattia ja sen nitraattipitoisuudet voivat nousta melko suuriksikin. Jääsalaatin nitraattipitoisuuteen vaikuttavat useat eri tekijät, kuten laji, lajike, lannoitustaso ja valon intensiteetti. Tehokkailla nitraattipitoisuuden hallintakeinoilla voidaan parantaa tuottajan mahdollisuuksia vaikuttaa sadon laatuun. Valtaosa ravinnon mukana saatavasta nitraatista on peräisin lehtivihanneksista. Euroopan unioni on asettanut katteen alla kasvatetun salaatin nitraattipitoisuudelle talvi- ja kesäkauden raja-arvot. Nitraatti on ihmisen terveydelle haitallinen yhdiste, sillä osa siitä muuttuu elimistössä nitriitiksi, mikä kasvattaa etenkin pienten lasten methemoglobinemian riskiä. Glysiinibetaiini on osmolyytti ja solun metabolian kanssa yhteensopiva yhdiste. Monet viljelykasvit syntetisoivat glysiinibetaiinia vasteena abioottisille stresseille ja se parantaa kasvien stressinkestävyyttä myös eksogeenisesti annettuna. Glysiinibetaiinia saadaan ravinnon mukana esimerkiksi viljatuotteissa ja se on ihmisille turvallinen yhdiste, jota voidaan käyttää myös ravintolisänä. Glysiinibetaiinia eristetään muun muassa sokerijuurikkaan melassista ja sitä voidaan käyttää orgaanisena lannoitteena tai kasvunedistäjänä kasvintuotannossa. Tämän tutkimuksen tavoitteena oli selvittää glysiinibetaiinin käyttömahdollisuuksia jääsalaatin tuotannon edistäjänä. Kasvihuonekokeessa seitsemän vuorokautta kestänyt glysiinibetaiinikäsittely aloitettiin jääsalaattien ollessa 29 vuorokauden ikäisiä. Glysiinibetaiinikäsittelyjen pitoisuudet olivat 0, 1, 7,5 ja 15 mM. Jääsalaatin nitraattipitoisuus, glysiinibetaiinipitoisuus sekä tuore- ja kuivamassa määritettiin 24, 29, 36, 41 ja 49 vuorokauden ikäisistä kasveista. Tutkimus toteutettiin kiertovesiviljelyjärjestelmässä ja glysiinibetaiinikäsittely annettiin ravinneliuoksessa. Jääsalaatit ottivat eksogeenisesti annettua glysiinibetaiinia. Glysiinibetaiinikäsittely pienensi jääsalaatin nitraattipitoisuutta seitsemän vuorokauden käsittelyn jälkeen merkitsevästi kontrolliin verrattuna ja alenema oli suoraan verrannollinen käsittelyn pitoisuuteen. Lisäksi glysiinibetaiinikäsittely pienensi jääsalaatin tuorepainoa ja suurensi kuiva-ainepitoisuutta. Määrityksissä myös jääsalaatin glysiinibetaiinipitoisuuden havaittiin olevan suoraan verrannollinen käsittelyn pitoisuuteen.
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(2018)Tämä tutkimus selvittää Googlen roolia maatalousyrittäjän ostopäätösprosessissa. Lisäksi tutkimus keskittyy siihen, miten maatalousyrittäjä suhtautuu Googlen esittämään hakusanamainontaan. Tutkimuksen teoreettinen tausta rakentuu aikaisempaan tutkimukseen organisaatiomarkkinoista, hakukonemarkkinoinnista ja maatalousyrittäjän ostokäyttäytymismallista. Teorian tavoitteena oli muodostaa käsitys siitä, mitä aikaisempi tutkimus kertoo tutkimusongelmaan liittyvistä asiakokonaisuuksista. Tutkimuksessa Google nähdään hakukoneena. Tutkimus toteutettiin haastattelemalla seitsemää maatalousyrittäjää vuonna 2018. Tutkimus on luonteeltaan kvalitatiivinen tutkimus. Aineistonkeruumenetelminä käytettiin puolistrukturoitua haastattelua ja havainnointia. Aineiston analyysi tapahtui sisällönanalyysin keinoin. Ostopäätösprosessia tutkittiin teorialähtöisesti. Tässä vaiheessa hyödynnettiin Websterin ja Windin (1972) luomaa kuvausta ostopäätösprosessin kulusta. Hakusanamainontaan liittyvät asiat analysoitiin aineistolähtöisesti. Analyysiä tuettiin muilla lähteillä ja aineistosta nostetuilla suorilla lainauksilla. Tarpeita nähtiin syntyvän Googlen välityksellä heikosti, mutta se koettiin mahdolliseksi. Tarpeita syntyi erityisesti hakusanamainonnan kautta. Eri ratkaisujen laatiminen Googlen avulla liitettiin taustainformaation saamiseen ja kansainvälistymiseen. Googlella nähtiin olevan eniten hyötyä tilanteissa, joissa ei ole kiire. Googlen käytön koettiin vaativan omaa ymmärrystä haetusta asiasta. Vaihtoehtojen haussa korostui tunnettavuus. Tämä aiheutti ankkuroitumisen tuttuun vaihtoehtoon. Vaihtoehtojen haku keskittyi usein nimen, sijainnin ja internetosoitteen löytymiseen. Kuvahaun merkitys korostui vaihtoehtojen nimien selvittämisessä. Vaihtoehtojen arviointi Googlessa perustui aineellisiin ja aineettomiin ominaisuuksiin. Arvioinnissa keskityttiin erityisesti hintaan, sijaintiin, luotettavuuteen ja tunnettavuuteen. Uuden toimittajan valinta Googlen välityksellä nähtiin mahdollisena, mutta vaikeana. Maatalousyrittäjät pyrkivät käyttäytymismalliin, missä Googlen mainoksia ei hyödynnetä osana hakua. Googlen hakusanamainontaan suhtauduttiin negatiivisesti maatalousyrittäjien keskuudessa. Maatalousyrittäjät käyttivät kuitenkin paljon Googlen hakusanamainonnan hakutuloksia. Googlen hakusanamainonnan koettiin aiheuttavan pettymyksiä useammin kuin luonnollisten hakutulosten. Tutkimuksen johtopäätöksenä voidaan todeta, että tällä hetkellä Googlella hakukoneena on merkittävä rooli maatalousyrittäjän ostopäätösprosessissa. Maatalousyrittäjän suhtautuminen Googlen hakusanamainontaan on kielteistä, mutta he hyödyntävät sitä merkittävissä määrin.
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(2015)This thesis aims to assess the state and development of beekeeping in Uruguay. Uruguay exports more than 90% of its honey and supplies regularly to the demanding markets in the EU and the US. As marginalized actors in the global honey chain, the beekeepers' livelihoods are largely dependent on the shifts of globalization, predominantly on the patterns of global economy. Proliferation of voluntary certification schemes such as Fairtrade International and European Union Organic Farming have become evident features of these patterns. Adoption of voluntary certification schemes has impacted particularly the development trajectories of smallholders, which is why particular attention in this thesis was laid on them. It was, however, quickly understood the development is dependent on several factors on different levels. To conceptualize these levels, value chain governance and voluntary certification schemes in them were seen shaping the livelihood outcomes of the smallholders. Combining governance and horizontal livelihood approaches, which represents the main innovation of this thesis, was used to identify action points and upgrading strategies feasible for the beekeepers as actors engaged in the global honey chain. In addition, this thesis further highlights the context of beekeeping as a livelihood, honey as a commodity with certain features and market dynamics, as well as Uruguay as the main geographical scope. Research methods were qualitative. Semi-structured interviews were conducted in 2014 with four different respondent groups along the global honey chain: importers of honey in the EU; representatives of local institutions and export agencies in Uruguay; and the beekeepers themselves, which of some were organized in cooperatives. From the collected data, the development trajectories were analyzed deductively to identify the viable strategies to improve sustainable livelihood outcomes. Based on results, the global honey chain was found buyer-driven since the buyers bear the most powerful role. The structure replicates features of market and captive types of governance, suggesting there is a high degree of power asymmetry and coordination. Higher coordination, however, favors successful upgrading. By identifying the activities performed by actors in the chain, the action point was found in the production node due to the recent increase in activities. High costs of inputs and low margins throughout the chain were observed, particularly in the export node. Beekeepers' baseline conditions were determined as access to livelihood assets, which were found generally weak. State of the fundamental aspect of beekeeping, access to natural assets, was found alarming. The decreased floral resources in Uruguay are due to the rapid proliferation of changes in land use, accelerated by the main vulnerability causing shocks in production and with implications on prices: the climate variability. A key finding, however, was that the proliferation of Eucalyptus grandis in Uruguay has created a dependency by compensating the losses in production based on other flowerings. Furthermore, the emergence of pests has brought risk of losing colonies and increasing costs in treatment and prevention. Natural assets set the main constraint over sustainability of beekeeping in Uruguay, but possibilities to compensate smallholders was found among social assets, which clearly were not optimized at their current levels. This notion largely represents the main conclusion in this thesis: horizontal contractualization of the beekeepers through collective action is the only strategy with a reasonable balance between revenues and risks. In all other scenarios, the risks are likely to become unbearable, unless an external agent would be willing to guarantee the risks up to some point to initiate the process. Collective action was found as a precondition of vertical contractualization, which could include affiliation in voluntary certification schemes. Fairtrade International was predominantly found as a more attractive scheme, but could in this context benefit only a large cooperative with already good resources. Affiliation in a certification scheme, however, would not remove the main constraints faced by the sector in Uruguay, which are the decreasing production per hive and the costs running relatively faster than the prices received, resulting in a decreasing profitability. Whereas more beekeepers are excluded from the chain, the ones remaining practice beekeeping largely based on love and tradition. Future research is suggested to take a more sophisticated approach to cost-benefit analyses to support further decision-making on the level of the beekeepers, as well as on the level of policy-makers. In addition, prospective approaches to develop and assess the potential of systems such as payments for ecosystem services in the context of beekeeping are highly recommended.
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(2020)Intercropping is an old agricultural practise to produce food and could be an interesting option to be utilized today. Use of legumes in mixtures can be a way to produce food more sustainably and minimize negative environmental impacts of current food production. Cultivation area of legumes have declined over recent years, due instability in yields and problems with pests and diseases. Intercropped systems can optimize use of land recourses and reduce issues with pest and disease. Furthermore, legumes could provide a more sustainable source for nitrogen than fossil fuels and more options for both feed and food production, especially for organic farming. Intercropping could also benefit diversity and add more options in crop rotations. In this field experiment intercropping with different mixtures of legumes and other non-legume crops were studied. This experiment by Swedish University of Agricultural Sciences was a part of the project Legumes for the agriculture of tomorrow (LEGATO). Project purpose was to promote and find solutions for increased and sustainable production of grain legumes in Europe. The main objectives of this thesis were to compare different crop mixtures and find benefits with intercropping, this thesis focused on peas and faba bean. Does intercropping add yield potential and can it have benefits for yield stability or pest damage. Results showed that intercropping did not benefit pea yields, but instead barley yields. Faba bean Gloria did benefit from intercropping, as did cereals. Yields indicate that more could be produced on the same area of land. Pest damage by pea moth (Cydia nigricana) had some statistical differences between treatments, but there were no similar effects on damage on faba bean by Broad bean weevil (Bruchus rufimanus).
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(2017)Bacteria can communicate with each other using phenomenon called quorum sensing (QS). In QS the bacteria produce and release small signaling molecules which they use to communicate. Bacteria use QS in situations where it is beneficial to act on population level. QS has an important role e.g. in the formation of virulence factors and biofilms. There are several different QS systems. Gram-negative bacteria use i.a AI-1, AI-2, AI-3, and CAI-1 systems to communicate. All QS systems are based on the accumulation of signaling molecules when the bacterial concentration increases. When the concentration of signal molecules reaches the threshold level, the system activates. The activation of the signaling system then activates the expression of the genes controlled by the QS system. AI-2 signaling is assumed to be universal. That means that bacteria can use AI-2 signaling system in interspecies communication. In AI-2 signaling bacteria produce and release 4,5-dihydroxy-2,3-pentanedione (DPD) which works as a signaling molecule in the AI-2 system. Escherichia coli and Salmonella typhimurium use an ATP binding cassette ABC-type transporter to transport DPD molecules into the cell where LsrK kinase phosphorylates the DPD molecules. The phosphorylated DPD molecules bind to the LsrR regulator protein which acts as a suppressor of the lsr operon. The binding of the phosphorylated DPD molecules releases the LsrR from the lsr promoter region enabling the expression of the lsr genes. In Vibrio harveyi the surface proteins LuxP and LuxQ form a protein complex that recognizes DPD molecules. When the DPD concentration increases, the LuxPQ complex transform from kinase to phosphatase and the reaction chain, where LuxU phosphate transfer protein transfers a phosphate group from LuxO regulator protein, activates. The dephosphorylation of of LuxO releases the LuxR transcription factor and activates the expression of QS controlled genes. The aim of this thesis was to optimize two assays which can be used to screen for compounds that disrupt AI-2 signaling. The first assay was a bioreporter based assay where V. harveyi BB120 bioreporter strain was used. The second assay was protein based LsrK assay where the LsrK activity was monitored using assay kit which measures the concentration of ATP or ADP. The concentrations of bacteria, LsrK, and DPD used in the assays were optimized. The dimethyl sulfoxide (DMSO) tolerance of both assays were tested, the stability of the kits used in the LsrK assays was tested and the reaction buffer for the LsrK assay was selected from the two tested buffer options. The selected bacterial concentration for the V. harveyi BB120 assay was 100000 CFU/ml and DPD concentration 1 µM. The selected enzyme concentration for the LsrK assay was 300 nM and DPD concentration 300 µM. The tested DMSO concentrations had no effect on the kit measuring ATP but the highest concentrations tested had a small effect on the kit measuring ADP. A buffer containing triethanolamine, magnesium chloride, and bovine serum albumin was selected as the reaction buffer for the LsrK assay. Using the optimized LsrK assay, a screening was performed for a synthesized compound library. None of the compounds showed any LsrK inhibiting activity. The optimized assay was also used to make dose-response experiment to one LsrK inhibiting compound, named FIMM000642, which was found in a separate screening. The FIMM000642 dose-response as-say was also done against glycerol kinase to see if the compound would inhibit another enzyme from the same protein family or if the compound was a specific inhibitor to LsrK. FIMM000642 inhibited also the activity of glycerol kinase.
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(2018)The concept of ecological management can be seen tackling the relationship of agriculture and environment, not only from the perspective of limiting the negative effects of farming practices, but also promoting positive actions. This notion of managing and maintaining, rather than leaving alone, is currently in the core of biodiversity promotion in agricultural landscapes in Europe. The focus of this thesis are the perceptions Finnish agri-environmental actors have regarding ecological management innovation stemming from the grassroots. In this thesis I assess how i) Finnish agri-environmental actors perceive grassroots innovation, ii) weigh its barriers and enabling factors, as well as iii) envision further needs regarding these innovations. The study is based on a mixed-methods approach using both qualitative and quantitative data; a questionnaire and two focus group discussions conducted during a two-day seminar “Managing Nature - working together” 29.11.-30.11.2016 in Turku. The study was conducted in co-operation with the Finnish Environment Institute (SYKE), University of Helsinki Faculty of Agriculture and Forestry and a Horizon2020 project HNV-Link. I approached the research questions using an iterative approach, and my analysis is guided by Grounded Theory in constant comparative analysis and generating theory. The results indicate that Finnish agricultural actors acknowledge the heterogeneous nature of grassroots actors in agricultural areas. However, several common attributes are linked to innovation stemming from the grassroots such as practical, economic and local. Currently bureaucracy, lack of cooperation and the changes and challenges in the socio-cultural environment of grassroots hinder ecological management grassroots innovation. Finnish agri-environmental actors acknowledge that the challenges biodiversity in agricultural areas face, are of such magnitude that the need is rather to expand, not narrow down the actor-base for innovation.
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(2015)This study provides the green (the share of rain water in crop production) and blue (the share of surface and groundwater in crop production) water footprint (WF) of four annual crops in Finland and five annual crops in Iran for the growing period 2007?2012. It aims to present more recent water footprint accounting on annual crops in this study. Due to the large scale water footprint accounting (country level), the calculation for grey water footprint was omitted from this study. The green and blue water footprints of barley, maize, oilseed rape, soybeans and wheat for Iran and barley, oats, oilseed rape, and wheat for Finland were calculated over the annual growing period 2007 to 2012. Crops were selected upon the availability of crop production in each country. WF values were estimated based on crop water use (CWU) and crop yield, where CWU was estimated upon the accumulative ET over the growing season of the crops. For daily evapotranspiration values AQUACROP model was used. For running the AQUACROP model, different parameters were needed such as climatic parameters (including minimum and maximum temperature, rainfall and potential evapotranspiration), soil type, land management, irrigation practice, groundwater and initial condition for sowing, sowing and harvesting dates. This data were mined from databases. Due to the fact that crop production in Finland is rain-fed, only green WF of the selected crops were calculated for Finland. In Finland oilseed rape had the highest average green water footprint per ton of production, which was 2471 m^3 t¯¹yr¯^1 and it was followed by oats (1036 m^3 t¯¹yr¯^1), wheat (944? m?^3 t¯¹yr¯^1), and barley (838? m?^3 t¯¹yr¯^1). Considering the annual crop production, the average total green water footprint of selected crops was 3669 Mm^3 yr¯^1 in Finland. Water saving through crop trade was estimated -294 Mm^3 yr¯^1. The negative saving water amount showed the virtual water loss through crop trade of selected crops in Finland. The highest export crop in Finland was oats during 2007?2012. In Iran the major share of annual crop production comes from irrigated crop lands and that shows the importance of blue water footprint accounting beside green water footprint. The sum of green and blue water footprints of the growing crops in Iran was considered as water footprint of the crops. Water footprint per ton of crops in Iran increased from maize (696 m^3 t¯¹yr¯^1), wheat (1235 m^3 t¯¹yr¯^1), barley (1350 m^3 t¯¹yr¯^1), soybeans (2210 m^3 t¯¹yr¯^1) to oilseed rape (3503 m^3 t¯¹yr¯^1). Total average water footprint of the selected crops in Iran considering their production in the country was estimated 22816? Mm?^3 yr¯^1. Regarding the crop trade balances in Iran, the country saved 8902? Mm?^3 yr¯^1 water by importing the crops. Wheat was the major import crop during 2007?2012. WF can be a strong tool for assessing the consumptive water use of the agricultural systems in place and time according to different agricultural and water managements. It can bring a ground for comparing the production sites for certain crops or products considering the lower WF of the produced items. This study aimed at producing recent calculations of water footprint of crops in Finland and Iran, using local data.
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(2017)The global trends have been guiding hotels to move to a green direction for years, and nowadays hotels are expected to maintain sustainability programs as a regular feature of their business. As the topic is receiving much more attention in hospitality, it is important to consider guests reactions to sustainable practices in hotels. In addition, customer participation is important of the implementation of green practices in hotels. The objective of this study is to investigate consumers’ general attitudes toward green hotels. Specifically, the study seeks to demonstrate how consumers evaluate green practices in hotels and how a hotel’s green image influences consumer decision- making. According to the findings of this thesis, consumers are willing to stay in green hotels and prefer green hotels. Survey study results demonstrate that respondents have positive or very positive attitudes toward green hotel image. This points out that green attributes can bring more value to the brand, and differentiate it from other hotel brands. Based on the literature review and survey study, this thesis distinguished three common green hotel marketing benefits, which are new market opportunities, green brand benefits, and competitive advantage which is achieved by product enhancement. Thus, this thesis demonstrates that there is market for green hotels and the best way to attract customers is to create green hotel brands that emphasize good and consistent value of the green hotel.
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(2017)Plenty of CO2 is commonly emitted from cultivated peat soils and substantial N2O emissions have occasionally been measured from acid sulphate soils. The factors limiting the emission of CO2 and N2O from the different layers of organic acid sulphate soil in Pärnänsuo were studied by aerobic and anaerobic incubation experiments. Two topsoil peat layers (upper and lower) and two mineral soil layers (upper and lower) were investigated. An aerobic experiment was carried out to see the emission of CO2 and N2O after application of glucose and ammonium, at two different temperatures (5o and 20o C). The water content of the soils was adjusted to 60% water- filled pore space (WFPS). Anaerobic experiment was carried out to assess the denitrification potential of different layers and the effect of glucose and nitrate alone and in combination as at 20oC using the acetylene inhibition technique. The lower peat layer exhibited more CO2 emission comparing to upper peat in the aerobic experiment. Additionally, in both peat layers and upper mineral soil layer, CO2 emission was increased exceedingly after glucose application. In the anaerobic experiment, potential denitrification from the upper peat was significantly higher than from other soil layers. Besides, the soil layers responded differently to C and N application. N2O emission from the upper peat was limited by easily available C whether it was applied as glucose alone or, in the presence of nitrate. On the contrary, N2O emission from lower peat layer was limited by nitrate with or, without glucose, but not by glucose alone. Both upper and lower mineral soil denitrification was limited by nitrate without glucose or, in combined with glucose, and not by glucose alone. Nitrogen mineralization pattern was different in upper and lower peat. A very high amount of NO3- was found in the upper peat, while there was a high amount of NH4+ in lower peat. Both the NO3- and NH4+ showed an increasing trend in lower mineral comparing to upper mineral, depicting an exceedingly high amount of mineral N at deeper layers
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(2022)Northern peatlands store approximately one-third of total global terrestrial carbon (C). These peatlands were partly drained for agriculture and forestry. In drained peatland forest, beside tree stands, ground vegetation is another relevant component concerning C fluxes between the land and the atmosphere. Thus, to explore ground vegetation gross primary production (GPPGV) dynamics, its affecting factors, and impacts of the partial harvest; forest floor net exchange (NEFF) and respiration (RFF) were measured on an hourly interval with an automated closed flux chamber method were analysed. These measurements were conducted in a forestry drained peatland before (pre-harvest, 2013 – 2015) and after (post-harvest, 2016 – 2017) the partial harvest and a control area (2015 – 2017) located in southern Finland. The results showed a similar diurnal pattern of GPPGV in all three scenarios yet, with a considerably varying magnitude between these scenarios. An 83% increase in photosynthetically active radiation (PAR) was observed in 2016 followed by the harvest event. However, a markedly higher GPPGV was obtained in the year 2017 (139.04 mg CO2 m-2 h-1) a year after the partial harvest compared to the year 2016 (42.82 mg CO2 m-2 h-1), thereby indicating a delaying effect of partial harvest induced changes on productivity. A linear mixed effect model with fixed effects of treatment (control and partial harvest) and random effects of chambers further supported this result with a significant effect of partial harvest on GPPGV in 2017 as compared to 2016. Further, a strong positive correlation was found between the daily mean GPPGV and PAR. Additionally, types of vegetation and its share of projection cover (PC) also explained GPPGV variations between flux chambers. An increase in GPPGV after the partial harvest event showed that the ground vegetation can play a considerable role in the C cycle of a managed drained peatland forest beside tree stands. As expected, after the partial harvest more lights reached the ground layer altering productivity. Besides light availability, productivity also depends on the types and phenology of inhabiting vegetation. Thus, exploration and realization of the response of ground vegetation to the partial harvest induced changes may contribute to our understanding of natural regeneration and system recovery processes.
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(2017)Bacteria are dominant members of the human gut microbiota, defined as the complex communities of microorganisms in the intestine which play an important role in regulating the health of their host, including the development of colorectal cancer (CRC). CRC is the fourth leading cancer-related mortality worldwide. Animal models are very useful in CRC research, as they allow studying molecular mechanism underlying the disease. Due to closer similarity to human beings in terms of nutrition and gastrointestinal physiology, pig models are of great value in research when compared with murine models. However, our current knowledge of the pig gut microbiome is still limited and a large number of gut bacterial species are yet to be isolated and characterised. Here, we characterised bacteria isolated from the intestine of wildtype pigs and transgenic APC1311/+ siblings (APC pigs) that develop colonic adenomas. A total of 12 novel bacteria, including 1 member of a potentially novel family, were identified from 256 strains isolated using anaerobic culturing. In addition, five other bacteria with a standing name in the nomenclature but not yet included in the pig collection were added. A draft genome was generated for four of the novel bacteria and thereby the functional potential of strains and compared their similarity. In addition, the morphology, bile salt hydrolase (BSH), 7α-dehydroxylation, carbohydrate fermentation, prevalence and abundance of all strains were analysed. The draft genome analysis confirmed the novel species status of the four bacteria. Furthermore, it also revealed the presence of genes associated with BSH, antibiotic resistance, butyrate production and carbohydrate utilization. Only two of 12 tested bacteria were positive for BSH, while none of the two bacteria selected for fermentation experiments was positive for 7α-dehydroxylation. One isolate of the species Paraclostridium benzoelyticum was found to exhibit significantly higher tolerance to NaCl than the same species described in the literature. In terms of prevalence, almost all of the bacteria (16 of 17) seem to be rare in pig, even though they appeared to be more enriched in the pig intestine when compared with other host species. Interestingly, the majority of positive samples for the bacterium representing the potentially novel family originated from the intestine of elderly human individuals. Overall, we could show that a substantial number of novel bacteria can still be isolated by classical anaerobic culture techniques using multiple rich or selective media. Even though we were able to identify most of the isolated bacteria and performed several assays to describe their properties, additional phylogenetic and taxonomic tests and development of optimal media/conditions for the novel bacteria are required in order to gain a deeper understanding of the role of these bacteria in the intestinal microbial ecosystem.
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(2020)Parkinson’s disease is a common neurodegenerative disorder that affects the movement. Although the disease has been known for a long time and intensive studies on this subject have been carried out, the cause of the disease is still unidentified. Interestingly, certain metallic molecules have been found in the neurodegenerative tissues. The metabolism of certain bacterial species has been found to be responsible for the accumulation of these molecules. In this study, we investigated the association between five specific species of gut bacteria, as well as their putative role in the accumulation of the metallic molecules and Parkinson’s disease. The methods comprised of molecular assays for detection and quantification of the bacteria, respectively, from feces samples derived from healthy individuals (n=20) and patients with the disease (n=20). The outcome of molecular assays was verified by traditional microbiological methods. The results suggested that more studies should be done to verify any role of these bacteria in Parkinson ́s disease.
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(2019)Inflammatory bowel disease (IBD) is a globally increasing chronic disease, for which the pathogenesis still is unclear. The most common subtypes of IBD are Crohn’s disease (CD) and ulcerative colitis (UC). It is widely known that, in addition to the genetics, an altered immune response against the gut microbiome plays an important role in the development of the disease. For the IBD patients, to whom conventional medication is not sufficient, the TNF-α blocker infliximab, is given. However, about one third of the patients receiving infliximab treatment, do not respond to the drug, or lose response over time. Since there to this day are no reliable diagnostic markers available, the finding of such is of great importance. The goal of this study was to investigate possible markers for drug response in the gut mycobiota composition of IBD patients. The gut mycobiota composition of 72 IBD patients receiving infliximab was studied by MiSeq sequencing of fungal DNA from fecal samples, collected during one year. The sequencing data was analyzed using the mare package in R. In addition, anti-Saccharomyces cerevisiae antibody (ASCA) concentrations were measured from baseline serum samples by ELISA. Finally, calprotectin concentrations were measured from baseline and twelve weeks post infliximab serum samples by ELISA to study whether serum samples could be used instead of fecal samples for measuring calprotectin values. Results show an increase of the Candida and Spiromyces genera in the gut mycobiota of non-responding patients at baseline. At all timepoints, the Spiromyces genus was observed at a higher abundance, compared to the group of patients responding well or partially to the medication. Interestingly, the increase of Candida was seen only in Crohn’s disease patients, when looking at the composition at all timepoints. ASCA values did not differ between the response groups. The serum calprotectin values did not correlate with fecal calprotectin, and serum calprotectin can thus not be used as a marker of gut inflammation. In conclusion, the gut mycobiota can offer predictive markers for drug response prediction to infliximab in IBD patients, which can with further studies offer a clinical diagnostic tool for prediction of drug response.
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