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Faculty of Agriculture and Forestry


Recent Submissions

  • Deoghare, Nazia Ajay (2022)
    The popularity of fermented beverages is on the rise due to signature flavours, associated health and nutritional benefits and a 100% natural label. Research in this sector is currently focused on industrial-scale production of traditional homemade fermented beverages such as Kombucha, Kefir and Kvass. To expand consumer choice beyond these traditional beverages and to provide more nutritional and flavor diversity, it is essential to develop novel products by using new microbial communities and new substrates. The industrial scale-up of fermented beverages produced using microbial communities is challenging as the flavour complexity and functionality of the beverage depends on the complex fermentation processes and interactions between the microbiota species. Fermentation systems that can separate the metabolic stages into separate fermentation steps would be needed to simplify and make the complex fermentation more efficient, scalable, and reliable. The aim of the thesis was to develop and compare different fermentation strategies to control the complex fermentation of previously isolated microbes to produce a bio-flavoured, low-alcohol, malt beverage with a signature fruity flavour and aroma. During the study, green-malt microbial species: Lactiplantibacillus plantarum, Saccharomyces cerevisiae and Saprochaete suaveolens were identified as significant contributors to the development of aroma and flavour compounds in the malt fermentates. Using the optimal cell concentration of the selected species, three different fermentation strategies: simultaneous inoculation, sequential inoculation and sequential fermentation were adopted to design five different fermentation systems. Cocktail blends of individual fermentates were also created and tested for flavour and aroma. All potential production methods were compared in contrast for parameters such as ease of operation, time-efficiency, flavour and aroma, and future scalability. The results showed that complex fermentation of the novel and low alcohol malt beverage could be controlled by selecting organoleptically significant microorganisms from the complex community, controlling the time and order of inoculation and using a stagewise or modular fermentation system. Sequential fermentation produced the desired low alcohol level and flavorful, fruity malt beverages. However, this system required centrifugation at each step and thus resulted in limited ease of operation. Sequential inoculation was an optimal and efficient method of controlling the fermentation since it required a single vessel, and the metabolic stages were separated by inoculating microorganisms sequentially with a 24 h time interval between each inoculation. Creating cocktail blends from individual fermentates also produced bioflavoured, fruity, aromatic, low alcohol malt beverages. This method was time-efficient with maximum ease of operation. The resulting beverages from these different fermentation systems were novel and had fruity flavours and aroma from the metabolites synthesized by organisms S. suaveolens, L. plantarum and S. cerevisiae. Thus, bio-flavoured, low-alcohol, malt beverages with signature fruity flavour and aroma were created at VTT. For the first time S. suaveolens was used in combination with L. plantarum and S. cerevisiae for beverage production using novel three-microbe fermentation systems to control complex fermentation.
  • Tuomela, Suvi Elina (2022)
    Water moulds belonging to genus Saprolegnia are known to be opportunistic fish pathogens and cause a deadly disease called saprolegniosis. Saprolegniosis is found in both wild and farmed fish as fish farms use natural waters as their fish-farming waters. Majority of cases of saprolegniosis found in fish farms are caused by Saprolegnia parasitica which is currently identified from dead fish by microscopic methods. This master's thesis was done for Finnish Food Authority. The aim of this thesis was to compare quantitative PCR (qPCR) methods in detection of S. parasitica and to evaluate the applicability of the best method. qPCR allows for better species identification than the microscopic method and it also enables the quantification of water mould DNA. The study was performed for three qPCR methods amplifying the gene region encoding S. parasitica aquatic mould 28S rRNA. Of the three methods, the best was selected based on specificity and sensitivity tests. The best method was used to detect and quantify S. parasitica in water samples from four Finnish fish farms. By this, the suitability of the method for water samples was confirmed. Also, data about the occurrence of S. parasitica water mould on fish farms was also collected. Based on the studies performed, the Roc-qPCR method based on the method developed by Rocchi et al. (2017) was selected as the best. The Roc-method was highly specific in identification of S. parasitica. With Roc- method, very low concentrations of S. parasitica DNA was quantified from fish farm water samples within good confidence. DNA amount of S. parasitica was statistically significantly higher in the effluent waters of fish farms, in which S. parasitica DNA levels were highest when water mould was detected in the fish farm fish. These results confirmed the notion that S. parasitica increases in fish. This increase of spores could be reliably detected by the Roc method. In the study, water temperature was not found to correlate with S. parasitica DNA, which may be due to the lack of data in the study. On the other hand, the occurrence of water mould is influenced by several other factors in addition to temperature, which were not considered in this study. Based on the results of this study, the Roc-qPCR method is a specific and sensitive method for the detection of S. parasitica from water samples. Roc-method is a potential method for use when designing of saprolegniosis control measures in fish farms. Further research is needed about the factors associated with the presence of S. parasitica in fish farms.
  • Henriksson, Roselia (2022)
    Tiivistelmä — Referat — Abstract Intestine renews itself from intestinal stem cells (ISCs) in response to cell damage and disease. Damaged and dead cells are replaced by ISCs through cell division followed by daughter cell differentiation. Disturbances in this process can lead to diseases such as cancer. Hexosamine biosynthetic pathway (HBP) is a mediator of systemic insulin signaling induced ISC proliferation. However, the full molecular mechanism of HBP mediated ISC proliferation is yet to be discovered. Deciphering the mechanisms of the regulation responsible for ISC renewal could pave way for disease etiology dependent on the rate of ISCs proliferation. In this project I use Drosophila genetic tools to elucidate transcriptional and translational level control of HBP regulated ISC proliferation. Glutamine Fructose-6-phosphate Amidotransferase (GFAT) activity limits the rate of N-Acetylglucosamine GlcNAc and consequently ISC proliferation. Thus, gfat2Δ1 mutant flies are used to study molecular regulation of HBP. Full midguts of Drosophila will be imaged using Aurox Clarity Spinning-disc Confocal system. Confocal 3D images will be analyzed using an image analysis software called linear analysis of midgut (LAM) to retain region specific data. Exploring ISC proliferation in relation to nutrient sensing pathways in the full midgut level is still novel and LAM provides region specific data in previously unprecedented detail. The end product of HBP pathway Uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) was supplemented within the diet of the flies to observe its effect to the gfat2Δ1 ISC phenotype. UDP-GlcNac did not rescue the gfat2Δ1 ISCs. Usage of Drosophila genetic tools elucidated previously unknown transcriptional level regulation of HBP induced ISC proliferation: ATF4 knockdown in gfat2Δ1 mutant ISCs rescued gfat2Δ1 attenuated ISC division. In addition, ATF4 was indicated to possibly regulate the gfat2Δ1 phenotype via the regulation of growth through ribosome biogenesis and 4EBP translation inhibition. This study revealed the mediator of HBP, the transcription factor ATF4 to be the modulator of ISC proliferation.
  • Kaplas, Venla (2022)
    Suomalaiset metsätilat ovat pirstoutuneet ja niiden keskikoko on pienentynyt. Pirstoutuminen on koettu uhaksi esimerkiksi teollisuuden puunsaannille ja metsäluonnon monimuotoisuudelle. Yhtenä keinona metsätilojen koon kasvattamiseksi pidetään metsien yhteisomistuksen lisäämistä ja tukemista. Suomen metsäkeskuksen, Maanmittauslaitoksen ja Tapion toteuttamassa Sujuvaan metsän-omistukseen 2025-hankkeessa pyritään tukemaan yhteismetsien ja metsäyhtymien toimintaa. Tämä tutkielma on toteutettu osana Sujuvaan metsänomistukseen 2025-hanketta, ja tutkielman tarkoituksena on selvittää, millaisia esteitä tai kannustimia yhteismetsien laajenemiseen liittyy, millaista tietoa ja palvelua yhteismetsät tarvitsevat laajentumisen tueksi sekä millaisia hallintopalvelutarpeita yhteismetsillä on. Lisäksi selvitetään, millaista tietoa ja palvelua yhteismetsät toivovat saavansa laajentumisen tueksi, ja millaisia toiveita yhteismetsillä on yhteismetsäverkkosivulle. Tutkimustuloksia hyödynnetään yhteismetsien palvelutarjonnan kehittämisessä. Tutkimusaineistona käytettiin Suomen metsäkeskuksen ja Tapion toimihenkilöiden keräämää haastatteluaineistoa, joka koostuu kesällä 2021 152 yhteismetsälle toteutetuista puolistrukturoiduista puhelinhaastatteluista. Tutkija koosti haastatteluvastaukset ja analysoi koottua aineistoa laadullisen teoriaohjaavan sisällönanalyysin menetelmin. Tulosten perusteella yhteismetsien laajenemisen esteenä ovat esimerkiksi tarjotun tiedon ristiriitaisuus, tiedon hajanaisuus ja metsätilojen korkea hintataso. Laajenemiseen kannustavia tekijöitä ovat esimerkiksi asiantuntijoiden tarjoaman tiedon laatu, hyvät materiaalit sekä muutokset metsänomistajakunnassa. Hallintopalveluihin liittyen yhteismetsät tarvitsevat osaavaa asiantuntijapalvelua esimerkiksi rahoitukseen ja kirjanpitoon. Yhteismetsäaiheisen verkkosivun kehittämiseen yhteismetsät suhtautuvat positiivisesti, ja internetsivu nähdään erityisesti hyvänä tietolähteenä sekä keinona välittää tietoa yhteismetsien toiminnasta myös yhteismetsiin kuulumattomille metsänomistajille. Tulosten tarkastelu SWOT-analyysin avulla auttaa hahmottamaan yhteismetsien palvelutarpeiden ulottuvuuksia ja erottamaan laajemmat yhteiskunnalliset tekijät sellaisista seikoista, joihin valtion virastot ja välillinen julkishallinto voivat omalla palvelutarjonnallaan vaikuttaa.
  • Autio, Johanna (2022)
    Finland is the world's seventh largest producer of softwood timber and the fourth largest exporter. Three-quarters of the approximately 12 million cubic meters of sawn timber produced annually are exported to more than 60 countries. The total annual value of exports in 2021 was approximately EUR 2.8 billion. Finnish sawmills are the backbone of the Finnish economy, but at the same time they are part of a global operating environment whose movements, directly or indirectly, affect product demand and prices, industry profitability, operating conditions, forest raw material prices, Finnish employment, Finland's GDP and society's well-being. This study was conducted as a collective case study. The aim of was to identify global weak signals that could be interpreted to anticipate short-term movements in the global sawn timber market. Also, the aim was to retrospectively identify potential events that have previously triggered or have been a driving force behind market developments and to provide sawmill operators a tool to anticipate these movements, prepare for possible events and support strategic planning. The research question of the thesis was the following: Are there identifiable similar signals or series of events that have had congruent effects on the development of the global sawn timber market in the 21st century? The purpose of the auxiliary research question was to deepen the understanding of the operating environment and the impact mechanisms of change. The auxiliary research question sought to establish whether the effects have been direct or indirect. The methods of future studies and business environment research are used in this research. The key elements in the study are PESTEL framework, scenario method and the future table. The study builds on previous future studies and the use of scenario methods, providing a perspective on a relatively little-studied industry. The study was conducted as an explanatory extensive case study. The research material consisted of industry and customs statistics for selected periods and semi-structured qualitative thematic interviews. Finnish long-term professionals in the export and trade of sawn timber, influencers from the domestic and foreign policy scene in the 21st century, and professionals in the economic and social sciences were selected for interviews. The interview material was themed and a future table describing the industry was built on the basis of it. Three different scenarios utilizing the narrative were formed from the future table. The research question was approached with the help of the PESTEL tool. It was used to map the phenomena shaping the global sawn timber market. Several different factors affecting the market were found. The study also showed that weak signals can be found in the context of the global timber trade. With regard to the auxiliary research question, all the weak signals observed in the research have had indirect effects on the operations of Finnish sawmills in a global context. The study showed that weak signals could be found in the operating environment of the global sawn timber market and that their effects on Finnish companies have been indirect. Since weak signals have occurred in the past, it is entirely expected that they are found now and, in the future, too. In order to succeed in a fast-paced and complex operating environment, it would be advisable for sawmills to build internal processes for a more diverse observation of the operating environment. The results of this study and the future table can be used in companies' strategy work and as a basis for their own scenarios.