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The literature review deals with water distribution in meat, the structure of the myofibrillar matrix, and the aspects related to the water-protein interaction. Special focus was given to the large water accessible area of myosin S1 units, surface hydrophobicity of proteins and factors affecting the hydrophobicity. Also the possible mechanisms of water-holding in meat were briefly introduced. The aim of the thesis was to study the effect of different ions and pH values on the surface hydrophobicity of the myosin S1 units, adding knowledge to the understanding of the interaction between myosin S1 units and water. Myosin S1 units were prepared from porcine longissimus dorsi muscle 48 h postmortem. Obtained myosin S1 units were subjected to 0.2 M, 0.4 M and 0.6 M ionic strength of NaCl and KCl and to pH 5.0, 5.5, 6.0, 6.5 and 7.0. The surface hydrophobicity of myosin S1 units was measured by fluorescent molecular probe (cis-Parinaric acid) method. The method of purifying myosin S1 units from porcine longissimus dorsi muscle 48 h postmortem was established under the conditions of our laboratory. Surface hydrophobicity was found to increase with increasing ionic strength of both KCl and NaCl. Concerning the different ions studied, only at 0.6 M, significantly higher surface hydrophobicity of myosin S1 units was measured in KCl compared to NaCl. This phenomenon is in accordance with chaotropic effect of K+ and Cl- and kosmotropic effect of Na+. Regarding the effect of pH, within KCl samples, more hydrophobicity myosin S1 unit was detected towards to the more acidic direction pH values than pH 6.0. For NaCl samples, at pH 5.5 and 6.0, surface hydrophobicity was significantly higher than at pH 5.0, 6.5 and 7.0. Differences may have been induced by the changes in the net charges of protein, and further in protein conformation. Considering the property of the protein surface, more hydrophobic protein results in less water-protein interaction. However, to look at the whole scenario of the interaction between myosin S1 units and water, changes of net charges of myosin S1 units and water structure at vicinity of them should be further studied.

Poultry meat has become popular in human diet and to secure the growing demand of poultry meat, breeders have developed broilers with fast growth and high breast muscle yield. Because of this genetic selection modern broilers are suffering from various quality defects in their breast muscles, one of which is called WB myopathy. The aim of the thesis was to study whether exercise, WB status or age have effects on ultimate pH and glycolytic potential (sum of total glucose and lactic acid content, given as lactate) in M. pectoralis major of modern broilers chickens. A total of 154 post-rigor breast muscle samples of male broilers of hybrid Ross 308 were used in this study. Broilers were divided randomly into three groups (A-C). Group A birds were not subjected to any exercise during the experiment. Group B birds lived 25 days exactly like group A but after that the drinking water dispensers was elevated to a higher level. Group C birds had their drinking water dispensers elevated to a 5 cm higher level after three days, and it was risen stepwise to 25 cm during the study. Broilers were slaughtered randomly from different groups at 20, 30 or 41 days old. Group B results were disregarded due to technical problems. Initial and ultimate pH, total glucose, free and in glycogen, and lactic acid contents for glycolytic potential, were determined from the breast muscle samples. The results showed that there were no differences between groups A and C (p > 0.05). There were differences between normal and WB cases in ultimate pH (pHu; p = 0.000), total glucose content (p = 0.000), lactate content (p = 0.007) and glycolytic potential (p = 0.000), but the pH values 5 minutes after death showed no significance (pH5; p = 0.190). There were differences in pHu, total glucose and glycolytic potential (p = 0.000), and lactate (p = 0.007), between ages 20, 30 and 41 days old birds. As the severity of WB increased in the breast muscle, the pHu increased and total glucose, lactate content and glycolytic potential decreased. The correlations showed significant relationships between WB score and all the above variables (p < 0.000). The results of the current study show that exercise does not have an effect on the levels of carbohydrates in M. pectoralis major of modern broiler chickens, but WB status and increasing slaughter age result a decrease in glycolytic potential and increase in ultimate pH.

Infant formulas are breast milk substitutes for 0 to 12-month-old infants. Addition of milk fat to infant formulas leads to an increase in solid fat content. Infant formulas are oil-in- water emulsions in which oil is dispersed into a continuous aqueous phase. Milk fat crystallization leads to partial coalescence and creaming which are types of instability in emulsions. Partial coalescence occurs when two droplets containing crystals collide and they partially coalesce by making contact between their oil phases. The aim of this thesis was to study if milk fat crystallization leads to partial coalescence which leads to a higher rate of creaming or the increasing density of crystallizing droplets leads to a lower rate of creaming. Also, the aim was to study the effect of interfacial layer on partial coalescence. Milk fat crystallization and emulsion stability were investigated from four series of oil-in- water emulsions containing different oils in different concentrations and either whey protein or lecithin as stabilizer. The samples were stored at 5, 20 and 40 °C and measured after 0, 7 and 28 days of storage. The crystallization of bulk fat and oil in emulsions were studied with melting enthalpies measured with differential scanning calorimetry. Emulsion stability was examined with particle size distribution, instability index and creaming velocity measurements. According to the results combining vegetable oil and butter oil, and emulsifying the fat decreases the total enthalpy change and crystallization onset temperature of oils. Mixing vegetable oil and butter oil before homogenization decreased crystallization onset temperature and total enthalpy change because the oils were in same droplet, and made the emulsions behave more like vegetable oil emulsions. Mixing the oils after homogenization made the emulsions behave similarly to butter oil emulsions. Whey protein was found to be a better stabilizer of emulsions than lecithin at 5 and 20 °C, but at 40 °C some Maillard reaction was noticed. It was suspected that the concentration of lecithin in emulsions was insufficient. Based on the results it could be stated that the increasing density due to crystallizing droplets made the emulsions more stable against creaming. Best stability of emulsions containing oil mixtures would be achieved if butter oil and vegetable oil were mixed after homogenization and whey protein used as emulsifier.

The primary objective of this thesis was to observe the effect of fermentation of oat and faba bean flour mixture on oat β-glucan. The secondary objective was to define how fermentation conditions affect β-glucan content, pH, total titratable acidity (TTA) and viscosity in oat-faba bean matrix utilizing experimental design and response surface methodology (RSM). As fermentation is a part of manufacturing process of plant-based yoghurt alternatives, this thesis observed the fermentation process in detail to define its effect on β-glucan. The flour mixture consisted of whole grain oat flour, oat bran concentrate, faba bean flour, faba bean protein isolate and water. This mixture was fermented with a commercial yoghurt starter, consisting of Bifidobacterium sbsp., Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus paracasei and Streptococcus thermophilus species. Studied fermentation condition factors were time (7 h, 12.5 h, 18 h), temperature (30 °C, 37.5 °C, 45 °C) and inoculum ratio (0.01 %, 0.1 %, 1% w/w). The relationship between the factors and responses were analyzed with the Central Composite Face-centered (CCF) design and response surface modelling. In all tested fermentation conditions, no significant decrease in β-glucan content was observed. However, relationships between fermentation condition factors and other responses were obtained. All factors had decreasing effect on pH and increasing effect on TTA. All factors contributed to viscosity, but temperature was significantly more effective than others, having positive, non-linear effect.

The effect of forest health and structure to the relative surface temperature captured by airborne thermal imagery was investigated in Norway Spruce-dominated stands in Southern Finland. Canopy surface temperature has long been recognized useful in monitoring vegetation water status. Recent studies have shown also its potential in monitoring vegetation health. Airborne thermal imagery, Airborne Light Detection and Ranging (LiDAR) and field measurements were acquired from the area of interest (AOI). The relative surface temperature correlated most negatively with the logarithm of stem volume, Lorey’s height and logarithm of basal area at resolution of 254m2 (9-m radius). In other words, taller and older stands had colder surface temperatures. In addition, LiDAR metrics, such as height percentiles and canopy cover percentage, were compared with surface temperature. Standard deviation of canopy height model, height features (H90, CHM_max) and canopy cover percentage were most strongly negatively correlated with the surface temperature. On average, higher surface temperatures were detected in defoliated canopies indicating that thermal images may provide some additional information for classifying forests health status. However, the surface temperature of defoliated plots varied considerably. It was also found that surface temperature differences between canopy and ground responses were higher in defoliated plots. Based on the results, forest health and structure affect to the surface temperature captured by airborne thermal imagery and these effects should be taken into account when developing forest health mapping applications using thermal imagery.

Nutrients get deposited in lake sediment from agricultural areas and other anthropogenic activities resulting in internal P loading and eutrophication. On the other hand, the situation with P rock (non renewable resource) used for production of mineral fertilizer is alarming that result in the depletion of P rock and increase P fertilizers price. The issue can be minimized by sediment removal and recycling nutrients from sediment for crop production. The existing results on sediment P availability for crops showed contradictory results and suggested that sediment P bioavailability for the crop is influenced by sediment iron to phosphorus mass ratio. However, comprehensive studies confirming their relationship are currently lacking. Hence, the study aims to determine the potential of sediment as fertilizers for crop (ryegrass) from several eutrophic lakes (in Finland and Estonia). The aim is to identify the effect of different lake sediments on ryegrass aboveground biomass and nutrient uptake. The study was conducted on greenhouse for around 6 months. Randomised complete block design was used for the experiment. The experimental treatments include sand with six different lake sediments: Peipsi, Lämmijärv, Kutajärvi, Kymijärvi, Matjärvi and Enonselkä basin of Vesijärvi, mineral fertilizer (positive) and without P fertilizer (negative) control. The biomass (yield) and nutrient uptake by the plants were measured and then analyzed for nutrient content. Significant effect of lake sediment was observed on ryegrass yield and P uptake. The significantly higher yield was observed for Lake Peipsi sediment treatment than in both controls. The ryegrass dry matter yield was greater in sediment treatments than negative control. Also, ryegrass yield was found to be greater in some sediment treatments than positive control. The concentration of nutrients (sulphur, calcium, magnesium, and potassium) was sufficient in ryegrass plant in all lake sediment treatments. The P uptake from Enonselkä sediment treatment was the highest whereas from Kutajärvi sediment treatment was the lowest. The P uptake was the highest (16.3 kg ha-1) in Enonselkä sediment treatment with the lowest Fe:P ratio of 12. Moreover, the result suggests that Fe:P mass ratio is one of the factors/sediment properties that determine P availability to the crops. However, other sediment properties may also affect P availability in the plants as organic P fraction was also used as an additional P source in some cases. The sediment increased C content and organic matter content compared to controls which improved ryegrass growth in sediment treatments. The increase in nutrient uptake and biomass in lake sediment treatments showed that lake sediment can be potential alternatives for fertilizers in nutrient deficient soil.

Potyviruses are positive-sense single-stranded RNA viruses that can alter several functions of their host plants and consequently, cause significant economic losses in the infected crop plants. During the viral infection, the host transcriptome changes. Stress related genes are triggered, and genes allowing for susceptibility are target for viral-induced modifications. Therefore, in this study, we investigated whether the expression of potential proviral genes SUO1, AGO1, and the major antiviral player AGO2 change in Nicotiana benthamiana (N. benthamiana) in response to potato virus A (PVA; genus Potyvirus) infection. Moreover, we aimed to determine whether helper component protease (HCPro) and active replication have a role in the transcriptional regulation of these genes. Leaves infected with PVA tagged with Renilla luciferase were collected at 3, 6, and 9 days postinoculation, and the viral gene expression was quantified with a dual-luciferase assay. Total RNA was isolated, cDNA was synthesized, and samples were analyzed through qPCR. BLAST hit results revealed that N. benthamiana has three homologs of the SUO1 gene. qPCR data showed no significant change in neither the expression of SUO1 homologs nor the expression of AGO1 during wild-type PVA infection. Moreover, the lack of HCPro or viral replication did not affect the expression of these genes. On the other hand, the expression of AGO2 was approximately 6 and 5 fold up-regulated at 6 and 9 days post-inoculation, respectively. In contrast with the wild-type PVA infection, the mutated viruses had a pronounced effect on AGO2 transcripts at 3 days post-inoculation. Replication-deficient viral RNA increased AGO2 expression circa four-fold, followed by the HCPro-deficient viral RNA increasing expression circa two-fold. AGO2, the major player involved in antiviral defense, was up-regulated during the wild-type infection. Active viral replication and functional HCPro played a role in AGO2 regulation. However, Agrobacterium infiltration can be accounted for interfering with the interpretation of the AGO2 results. Although SUO1 and AGO1 may be potential genes allowing for susceptibility, this study revealed that the PVA infection does not affect the mRNA expression of these genes. Furthermore, it is concluded that active HCPro and viral replication do not have a role in the expression of these genes on mRNA level. To have a clearer view, integrating small RNA, mRNA, and protein quantification analysis of SUO1 homologs will be necessary. Keywords

Soil carbon sequestration is one of the most promising solutions to mitigate climate change. Biochar, a carbon rich solid obtained via pyrolysis and intended to be used as a soil amendment material, is currently the most efficient tool available for carbon sequestration. Further, some biochars can also improve soil properties and increase crop yield. Before the concept of using biochar as soil amendment can be implemented in a bigger scale, it is necessary to know how biochar affects soil fauna in long term. Earthworms present one of the largest animal biomass in soil. They feed on decomposed organic matter and also biochar and transfer it to pedosphere. Effect of biochars and fertilizers on earthworm abundance, biomass and community structure was studied in two field experiments, one on fertile Stagnosol and other on nutrient deficient Umbrisol. In both study sites, split-plot experiments with four replicates were arranged. The earthworms were sampled more than four and five years after the biochar have been applied to the fields on Umbrisol and Stagnosol, respectively. No significant effect of biochar or fertilizer treatments or their interactions were found on earthworms communities, suggesting biochar to be a safe method for carbon sequestration in Southern Finland conditions. The composition of earthworm species was typical for Finnish agricultural land with A. caliginosa dominating in both soils. However further research on long-term experiments are needed, in order to fully understand mechanisms of biochar effects on earthworms.

Biochar, produced by heating biomass in oxygen-limited environments, is known for its potential to reduce methane emissions, by altering rumen fermentation. However, the literature lacks exploration on how biochar affects nutrient digestibility and ruminal methane production across various diets. Therefore, we examined the effects of spruce (Picea abies) biochar on several forage plant species options and forage-to-concentrate (F:C) ratios. Two in vitro trials of 24 hours were conducted with Gas Endeavour® equipment at Animal Science laboratory of the University of Helsinki. There were three rumen fluid donor animals and the ratio of rumen fluid and McDougall’s buffer was 1:2 (vol:vol). The first trial tested biochar levels (0%, 0.25%, and 0.5% of diet dry matter (DM)) with four silage options that were pure grass (Phleum pratense – Festuca pratensis), grass mixed 1:1 in DM with red clover (Trifolium pratense), faba bean (Vicia faba), or maize (Zea mays L) at a fixed F:C ratio of 65:35. The concentrate consisted of oats and rapeseed meal. The second trial explored the effects of the biochar (0.5% of diet DM) and an alternative methane inhibitor (product X) alone or combined across 65:35 and 45:55 F:C ratios. Key parameters such as total gas and methane production, DM digestibility, rumen fluid pH, and volatile fatty acid (VFA) concentrations were analyzed. Grass silage (D-value 669, neutral detergent fiber (NDF) 523 g/kg DM) and red clover silage (D-value 626, NDF 362 g/kg DM) were harvested from the first cut. Maize silage was more digestible than faba bean silage (D-value 679 vs. 593 g/kg DM) and contained more starch (278 vs. 48 g/kg DM). High forage diet (65:35) had higher NDF content (453 vs 407 g/kg DM) and lower starch content (114 vs 179 g/kg DM) than low forage diet (45:55). Biochar's effect on DM digestibility and the production of rumen methane or carbon dioxide was not significant across different silage plant species and F:C ratios. Grass silage led to lower total methane production compared to silage mixtures (p<0.05), and the combination of biochar and product X in a low forage diet numerically reduced gas production. However, when methane production was calculated per digested DM, no differences were observed. Feeding maize silage increased the total production of methane and carbon dioxide in the rumen compared to faba bean silage (p<0.001), but gas productions per digested DM remained unaffected. Biochar did not significantly affect final rumen pH across silage species. Biochar with grass silage linearly reduced the total VFA content of the rumen fluid (p=0.003) and had tendency for smaller molar proportion of acetic acid in VFA (p= 0.075). In the second trial biochar or product X didn´t have significant effect on rumen fermentation pattern across forage levels. The effects of biochar, silage plant species and F:C ratios on in vitro rumen fermentation and methane production were minimal, despite differences in diet composition.

It is important to study the factors which inhibit the cultivation of major crops which serve as a source of food and feed, with various other medicinal values as well. One of these factors is soil degradation and infertility which could be due to high amounts of toxic elements or unfavourable pH conditions. Faba bean is one such crop and is widely affected by the acidity and aluminium toxicity in soil. In this study, an effort has been made to observe the varying tolerance of faba bean accessions and understand the underlying mechanisms used by them under stress conditions. The accessions selected were Aurora, Babylon and Kassa. Each accession was subjected to three treatments and were grown in pH 7 (control), pH 4.5 (acid treatment) and pH 4.5 + Al3+ (aluminium treatment). The pH of peat for acidic treatment was reduced to 4.5 using Sulphuric acid (H2SO4) and for aluminium treatment, Aluminium sulphate (Al2(SO4)3) was added in addition to the acid. At 16 Day after Sowing (DAS) and 30 DAS the physiological data was collected which comprised of chlorophyll concentration (SPAD value), stomatal conductance, leaf temperature and photosynthesis rate. At 35 DAS, the experiment terminated and the shoot data (fresh and dry weights of leaves and stem; and leaf area) of each plant was recorded. Then the root data (tap root length, quality and quantity of nodules and photographs of roots) was taken for each plant. ICP samples for peat, shoot and shoot were also analysed. The data collected were subjected to analysis of variance using R version 4.0.3. (means separated by 5% significance level). From the plant data, Aurora was found to be tolerant. Kassa was sensitive (especially the roots) and Babylon was sensitive to both acid and aluminium treatments. The ICP results provided the reason for this tolerance pattern and a higher concentration of elements needed for plant growth such as P and S were found to be higher in aluminium and acid treatments.