Food Safety Testing: Rapid Molecular Methods for Chemical and Biological Hazards

The central goal of food safety policy in the European Union (EU) is to protect consumer health by guaranteeing a high level of food safety throughout the food chain. This goal can in part be achieved by testing foodstuffs for the presence of various chemical and biological hazards. The aim of this study was to facilitate food safety testing by providing rapid and user-friendly methods for the detection of particular food-related hazards. Heterogeneous competitive time-resolved fluoroimmunoassays were developed for the detection of selected veterinary residues, that is coccidiostat residues, in eggs and chicken liver. After a simplified sample preparation procedure, the immunoassays were performed either in manual format with dissociation-enhanced measurement or in automated format with pre-dried assay reagents and surface measurement. Although the assays were primarily designed for screening purposes providing only qualitative results, they could also be used in a quantitative mode. All the developed assays had good performance characteristics enabling reliable screening of samples at concentration levels required by the authorities. A novel polymerase chain reaction (PCR)-based assay system was developed for the detection of Salmonella spp. in food. The sample preparation included a short non-selective pre-enrichment step, after which the target cells were collected with immunomagnetic beads and applied to PCR reaction vessels containing all the reagents required for the assay in dry form. The homogeneous PCR assay was performed with a novel instrument platform, GenomEra^™, and the qualitative assay results were automatically interpreted based on end-point time-resolved fluorescence measurements and cut-off values. The assay was validated using various food matrices spiked with sub-lethally injured Salmonella cells at levels of 1-10 colony forming units (CFU)/25 g of food. The main advantage of the system was the exceptionally short time to result; the entire process starting from the pre-enrichment and ending with the PCR result could be completed in eight hours. In conclusion, molecular methods using state-of-the-art assay techniques were developed for food safety testing. The combination of time-resolved fluorescence detection and ready-to-use reagents enabled sensitive assays easily amenable to automation. Consequently, together with the simplified sample preparation, these methods could prove to be applicable in routine testing.

Sensory and Non-sensory Factors Behind the Liking and Choice of Healthy Food Products

A healthy and balanced diet can reduce health problems, such as overweight and metabolic syndrome. In general, people have a considerably good knowledge of what constitutes a healthy diet and how they could achieve it with their food choices. Besides, people argue that health is among their top five food choice motives. Nevertheless, the prevalence of overweight is increasing and other food choice motives, such as taste, seem to conflict with the health. Liking for food does not necessarily determine acceptance alone, thus several non-sensory factors, such as brand, country of origin and nutrition claim, can also influence. Moreover, consumers are individuals in how they prioritize sensory and nonsensory factors of foods, but e.g. increasing age, female gender and health concern have been connected to a more health-oriented dietary behaviour. To sum up, identifying different factors that can increase the liking and consumption of healthy food is essential in order to develop more attractive healthful food products. Adding vitamins, minerals, fibre or other ingredients to a food product can be used to enrich the nutritional quality of the products. However, this may be difficult in practice as regards the sensory quality and pleasantness of the foods. Generally, consumers are not willing to compromise on taste in food. On the other hand, consumers are very heterogeneous in their likings, and their personal values and attitudes may interact with preferences for specific sensory characteristics. The aims of this study were to investigate the effects of intrinsic product characteristics on sensory properties and hedonic responses; to determine the impact of few non-sensory factors; and to examine the interaction between sensory and non-sensory factors with consumers’ demographics, values and attitudes in liking of healthy model foods. The results showed that product composition influenced sensory quality and had an effect on hedonic responses. Adding flaxseed to bakery products showed a significant improvement in the nutritional quality without negative effects on sensory properties. On the other hand, the fortification of wellness beverages with vitamins and minerals may impart off-flavours. In general, sweetness of yoghurts, freshness of wellness beverages and low intensity of rye bread flavour appealed to consumers. Information about the domestic origin of yoghurts and claiming a specific function for wellness beverages enhanced liking. However, consumers who were more concerned about their health and considered natural content as an important food choice motive, rated sourer and less sweet yoghurts and wellness beverages as more pleasant. In addition, interest in health increased the consumption of rye breads and other whole grain breads among adolescents. The results showed that the optimal product quality in terms of intrinsic and extrinsic factors differs between individual consumers, and personal values and food choice motives can be connected to preferences for specific sensory characteristics of foods. This indicates that each food product needs to be considered in relation to its specific market niche, and to which segment of consumer will respond most positively to its characteristics.

Integration of the Food Waste Disposer Unit to the Existing Sewage System

Among the numerous approaches to food waste treatment, the food waste disposers method (FWDs), as a newcomer, has become slowly accepted by the general public owing to the worries about its impact on the existing sewage system. This paper aims to justify the role of FWDs in the process of urbanization in order to better prepare a city to take good care of the construction of its infrastructure and the solid waste treatment. Both the literatures and the case study help to confirm that FWDs has no negative effects on the wastewater treatment plant and it is also environmental friendly by reducing the greenhouse gas emissions. In the case study, the Lappeenranta waste water treatment plant has been selected in order to figure out the possible changes to a WWTP following the integration of FWDs: the observation shows only minor changes take place in a WWTP, in case of 25% application, like BOD up 7%, TSS up 6% and wastewater flowrate up 6%, an additional sludge production of 200 tons per year and the extra yield of methane up to 10000m3 per year; however, when the utilization rate of FWD is over 75%, BOD, TSS, and wastewater flowrate will experience more significant changes, thus exerting much pressure on the existing WWTP. FWDs can only be used in residential areas or cities equipped with consummate drainage network within the service sphere of WWTP, therefore, the relevant authority or government department should regulate the installation frequency of FWDs, while promoting the accessory application of FWDs. In the meanwhile, WWTP should improve their treatment process in order to expand their capacity for sludge treatment so as to stay in line with the future development of urban waste management.

Catalytic transformations of fatty acid derivatives for food, oleochemicals and fuels over carbon supported platinum group metals

Växtoljor som utgör en förnybar naturresurs används som sådana eller i modifierade former i många industriella processer, som är av stor betydelse för vårt vardagliga liv. Växtoljor används i livsmedel, i kemiska och farmaceutiska produkter, i textilindustrin, för framställning av färgämnen och beläggningsmaterial samt som miljövänliga bränslekomponenter. Fetter och oljor hör till de äldsta kemiska komponenterna som utnyttjas av människan. De består huvudsakligen av glycerolestrar och fettsyror. Fetter och oljor har typiskt en kolkedja med kol-koldubbelbindningar samt karboxyl- och estergrupper, som kan genom hydrering eller dekarboxylering konverteras till nyttiga och miljövänliga produkter med hjälp av ädelmetallkatalysatorer. Aktivt kol (C) används som bärare på katalysatorerna. Väteaddition, d.v.s. hydrering av växtoljor har varit föremål för omfattande forskning i över hundra års tid. Hydreringen är en viktig process, för den tillämpas på produktion av fetter och margarin. Omättade fettsyror hydreras traditionellt på nickelbaserade heterogena katalysatorer. Samtidigt med en partiell hydrering av fettsyrorna och fettsyraestrarna som har två dubbelbindningar pågår också isomeringsreaktioner, vilka ger cis- och transisomerer av reaktantmolekylerna. Den största nackdelen med nickelkatalysatorerna är deras giftighet samt bildning av ohälsosamma transisomerer i reaktionsprodukterna. Dessutom deaktiveras nickelkatalysatorn snabbt p.g.a. att nickeltvålar bildas i reaktionsblandningen. Platinabaserade katalysatorer lider däremot inte av dessa begränsningar. Metaller i platinagruppen i det periodiska systemet studerades i detalj för att avslöja kinetiska effekter i hydreringen av cis-metyloleat. Palladium, rutenium, rhodium, platina och iridium användes som katalytiska metaller. Metallhalten på aktivkolbärare var 1 vikt-%. De olika platinametallerna undersöktes för att kartlägga konkurrerande hydrerings- och isomeringsrutter på metallerna. Det visade sig att metallerna i andra raden av det periodiska systemet (Ru, Rh, Pd) är aktivare i isomeringsprocesserna, medan metallerna i tredje raden (Ir, Pt) har en lägre aktivitet. Pd/C valdes bland platinametallerna, för att den är attraktiv ur ekonomisk synvinkel och den är mycket aktiv och selektiv, speciellt jämfört med nickel. Tyngdpunkten i arbetet var utvecklingen av en alternativ, palladiumbaserad hydreringsteknologi som skulle ersätta den traditionella teknologin som är baserad på användningen av nickelkatalysatorer. Palladiumbaserade katalysatorer kan återcirkuleras, de är aktivare och mera resistenta mot syror och de bildar mindre mängder av skadliga transisomerer. För att denna teknologi skall bli ekonomiskt hållbar och konkurrenskraftig, måste den basera sig på de bästa möjliga katalysatorerna, vilket innebär att en optimal kombination av hög aktivitet och selektivitet samt en lång livstid för katalysatorn krävs. Därför inkluderades teknologiska aspekter kraftigt i forskningen. Mycket arbete satsades på design av palladium på en mesoporös kolbärare och undersökning av korrelationerna mellan katalysatorns egenskaper och dess aktivitet i isomeriseringsreaktionerna och i hydreringen av kol-koldubbelbindningarna i reaktantmolekylen. Katalysatorerna karakteriserades med många fysikaliska och kemiska metoder (transmissionselektronmikroskopi (TEM), röntgendiffraktion (XRD), röntgenfotoelektronspektroskopi (XPS), temperaturprogrammerad reduktion (TPR), temperaturprogrammerad desorption (TPD) av kolmonoxid, kemisorption av kolmonoxid, fysisorption av kväve). Temperaturens, vätetryckets och katalysatorkoncentrationens inverkan på fettsyra- och isomersammansättningen hos de hydrerade oljorna bestämdes under kinetiska betingelser, i frånvaro av massöverföringseffekter. Syreavspjälkning genom fullständig dekarboxylering av karboxylgruppen i fettsyramolekylen är det hittills bästa sättet att framställa miljövänlig dieselolja, eftersom linjära paraffiner fås som reaktionsprodukter och en tillsats av dyr vätgas undviks. Deoxygeneringen undersöktes systematiskt på en Pd/C-katalysator (Sibunit) genom att använda mättade fettsyror C16-C20 och C22 som råvara. Produktmolekylen blev en dieselliknande kolvätemolekyl, med en kolatom färre än i utgångsmolekylen. Lika stora dekarboxyleringshastigheter observerades för rena, mättade fettsyror. En jämförelse av deoxygenereringshastigheterna för stearin-, olein- och linolsyra som råvara vid 300oC i närvaro av 1-volymprocent väte på mesoporös Pd/C (Sibunit) avslöjade att katalysatorns aktivitet och selektivitet ökade med en ökande mättningsgrad av reaktantmolekylen. Då stearinsyra användes som utgångsmolekyl, bestod huvudprodukterna av önskade C17-kolväten, medan mängden av aromatiska C17-komponenter ökade, då olein- och linolsyra användes som utgångsmolekyler. Katalysatordeaktiveringen var relativt påfallande vid deoxygeneringen av linolsyra så att endast 3% av fettsyrorna omsattes till produkter i 330 min. Deaktiveringen orsakades av aromatiska C17-komponenter samt av fettsyradimerer, som bildades via en Diels-Alderreaktion. Hydreringen av omättade fettsyror kan därför rekommenderas som ett primärt kemiskt steg i framställningen av miljövänliga dieselprodukter. Målet var också att öka förståelsen av palladiummetallernas roll i nanoskala, speciellt effekten av metallpartiklarna i katalytisk hydrering och deoxygenering. Pd/C-katalysatorer med lika stora halter av Pd syntetiserades och metallens dispersion på bärarmaterialet varierades systematiskt genom en kontrollerad uppväxt av palladiumnanopartiklar på aktiv kolbärare. Metalldispersionens effekt på hydrerings-hastigheten och cis-transförhållandet undersöktes i detalj. En optimal metalldispersion som gav den högsta dekarboxyleringshastigheten hittades. Massöverföringens inverkan på reaktionens hastighet studerades experimentellt och temperaturprogrammerad desorption av kolmonoxid från katalysatorytan undersöktes ingående. Hydrering av växtoljor genomfördes under satsvisa och kontinuerliga betingelser. Både finfördelat Pd/C och katalysatorgranulat användes i experimenten. Ett av målen med arbetet var uppskalningen av hydreringsprocesserna. Med tanke på stora produktionsvolymer var det logiskt att undersöka kontinuerliga hydrerings- och dekarboxyleringsteknologier. En kontinuerlig packad bäddreaktor studerades i laboratorieskala, vilket gav viktig information om katalysatorns långtidsstabilitet och deaktivering. Effekten av rena fettsyror och triglycerider som råvara samt metallpartikelstorleken och palladiumhalten studerades med hjälp av den kontinuerliga reaktorn. Produktionskapaciteten som erhölls med satsvis och kontinuerlig drift jämfördes. Dekarboxyleringen av stearinsyra undersöktes också i en kontinuerlig packad bädd. Omsättningsgraden blev 15% för en stabil katalysator.

Astringent Food Compounds and Their Interactions with Taste Properties

Astringency is traditionally thought to be induced by plant tannins in foods. Because of this current research concerning the mechanism of astringency is focused on tannin‐protein interactions and thus on precipitation, which may be perceived by mechanoreceptors. However, astringency is elicited by a wide range of different phenolic compounds, as well as, some non‐phenolic compounds in various foods. Many ellagitannins or smaller compounds that contribute to astringent properties do not interact with salivary proteins and may be directly perceived through some receptors. Generally, the higher degree of polymerization of proanthocyanidins can be associated with more intense astringency. However, the astringent properties of smaller phenolic compounds may not be directly predicted from the structure of a compound, although glycosylation has a significant role. The astringency of organic acids may be directly linked to the perception of sourness, and this increases along with decreasing pH. Astringency can be divided into different sub‐qualities, including even other qualities than traditional mouth‐drying, puckering or roughing sensations. Astringency is often accompanied by bitter or sour or both taste properties. The different sub‐qualities can be influenced by different astringent compounds. In general, the glycolysation of the phenolic compound results in more velvety and smooth mouthdrying astringency. Flavonol glycosides and other flavonoid compounds and ellagitannins contribute to this velvety mouthdrying astringency. Additionally, they often lack the bitter properties. Proanthocyanidins and phenolic acids elicit more puckering and roughing astringency with some additional bitter properties. Quercetin 3‐O‐rutinoside, along with other quercetin glycosides, is among the key astringent compounds in black tea and red currants. In foods, there are always various other additional attributes that are perceived at the same with astringency. Astringent compounds themselves may have other sensory characteristics, such as bitter or sour properties, or they may enhance or suppress other sensory properties. Components contributing to these other properties, such as sugars, may also have similar effects on astringent sensations. Food components eliciting sweetness or fattiness or some polymeric polysaccharides can be used to mask astringent subqualities. Astringency can generally be referred to as a negative contributor to the liking of various foods. On the other hand, perceptions of astringent properties can vary among individuals. Many genetic factors that influence perceptions of taste properties, such as variations in perceiving a bitter taste or variations in saliva, may also effect the perception of astringency. Individuals who are more sensitive to different sensations may notice the differences between astringent properties more clearly. This may not have effects on the overall perception of astringency. However, in many cases, the liking of astringent foods may need to be learned by repetitive exposure. Astringency is often among the key sensory properties forming the unique overall flavour of certain foods, and therefore it also influences whether or not a food is liked. In many cases, astringency may be an important sub‐property suppressed by other more abundant sensory properties, but it may still have a significant contribution to the overall flavour and thus consumer preferences. The results of the practical work of this thesis show that the astringent phenolic compounds are mostly located in the skin fractions of black currants, crowberries and bilberries (publications I–III). The skin fractions themselves are rather tasteless. However, the astringent phenolic compounds can be efficiently removed from these skin fractions by consecutive ethanol extractions. Berries contain a wide range of different flavonol glycosides, hydroxycinnamic acid derivatives and anthocyanins and some of them strongly contribute to the different astringent and bitterness properties. Sweetness and sourness are located in the juice fractions along with the majority of sugars and fruit acids. The sweet and sour properties of the juice may be used to mask the astringent and bitterness properties of the extracts. Enzymatic treatments increase the astringent properties and fermented flavour of the black currant juice and decrease sweetness and freshness due to the effects on chemical compositions (IV). Sourness and sweetness are positive contributors to the liking of crowberry and bilberry fractions, whereas bitterness is more negative (V). Some astringent properties in berries are clearly negative factors, whereas some may be more positive. The liking of berries is strongly influenced by various consumer background factors, such as motives and health concerns. The liking of berries and berry fractions may also be affected by genetic factors, such as variations in the gene hTAS2R38, which codes bitter taste receptors (V).

Rural Food System Change in Tanzania during the Post-Ujamaa Era. A Case Study from Western Bagamoyo District

Food systems in Sub-Saharan Africa have been rapidly transforming during the recent decades with diverse outcomes on human development and environment. This study explores the food system change in rural villages in eastern Tanzania where subsistence agriculture has traditionally been the main source of livelihood. The focus is on the salient changes in the spatial dimensions and structural composition of the food system in the context of economic liberalization that has taken place after the end of the socialist ujamaa era in the mid-1980s. In addition, the linkages of the changes are examined in relation to food security, socio-economic situation, livelihoods, and local environment. The approach of the study is geographical, but also involves various multi-disciplinary elements, particularly from development studies. The research methods included thematic and questionnaire interviews, participatory tools, and the analysis of land use/ cover data and official documents. Several earlier studies that were made in the area during the late 1970s and 1980s provided an important reference base. The study shows that subsistence farming has lost its dominant role in food provisioning due to the declining productivity of land, livestock losses, and the increasing shift of labour to non-farm sectors. Also rapid population growth has added to the pressure on land and other natural resources. Despite the increasing need for money for buying marketed foods and other necessities, the nutritional situation shows improvement and severe malnutrition has diminished. However, the long-term sustainability of this transformation raises concerns. Firstly, the food security situation continues to be fragile and prone to shocks such as adverse climatic conditions, crop failures and price hikes. Secondly, the commodification of the food system and livelihoods in general is linked to rapid environmental degradation in the area, particularly the loss of soil fertility and deforestation. The situation calls for efforts that take more determined and holistic approaches towards sustainable development of the rural food system with particular focus on the role and viability of small-scale farming.

Packaging inks for folding cartons used in food packaging

This thesis examined packaging inks suitable for folding cartons used in food packaging. The recent cases of compounds migrating from packaging inks into packed food, have forced the packaging ink manufacturers to develop inks that do not include substances at a level, that may pose a risk to the health of a consumer or to the quality of packed food. Food packaging is a sensitive area and subject to extensive legislation. This research presents the current situation on regulatory documents that can be used to demonstrate the safety of packaging inks used in food packaging. In the research, data was also collected on the available packaging inks for food packaging in packaging ink market. Test printing was performed with five printing inks and three varnishes on Ensocoat board, produced by Stora Enso. Tests results regarding print quality, runnability, sensory properties and migration were analysed. The packaging inks with the finest performance in the tests were ultra violet curing printing ink and varnish. The results showed that ultra violet curing printing technology in food contact applications is an important research area, with further research possibly being able to redeem the UV technologies' bad reputation within the packaging supply chain.

Andean indigenous food crops: nutritional value and bioactive compounds

The Andean area of South America is a very important center for the domestication of food crops. This area is the botanical origin of potato, peanut and tomato. Less well- known crops, such as quinoa (Chenopodium quinoa), kañiwa (Chenopodium pallidicaule) and kiwicha (Amaranthus caudatus), were also domesticated by ancient Andean farmers. These crops have a long history of safe use with the local populations and they have contributed to the nutrition and wellbeing of the people for centuries. Several studies have reported the nutritional value of Andean grains. They contain proteins with a balanced essential amino acid composition that are of high biological value, good quality oil and essential minerals, for example iron, calcium and zinc. They are potential sources of bioactive compounds such as polyphenols and dietary fiber. The main objective of the practical work was to assess the nutritional value of Andean native grains with a special emphasis on the bioactive components and the impact of processing. The compounds studied were phenolic acids, flavonoids, betalains and dietary fiber. The radical scavenging activity was measured as well. Iron, calcium and zinc content and their bioavailability were analyzed as well. The grains were processed by extrusion with the aim to study the effect of processing on the chemical composition. Quinoa, kañiwa and kiwicha are very good sources of dietary fiber, especially of insoluble dietary fiber. The phenolic acid content in Andean crops was low compared with common cereals like wheat and rye, but was similar to levels found in oat, barley, corn and rice. The flavonoid content of quinoa and kañiwa was exceptionally high. Kiwicha did not contain quantifiable amounts of these compounds. Only one variety of kiwicha contained low amounts of betalains. These compounds were not detected in kañiwa or quinoa. Quinoa, kañiwa and kiwicha are good sources of minerals. Their calcium, zinc and iron content are higher than the content of these minerals in common cereals. In general, roasting did not affect significantly mineral bioavailability. On the contrary, in cooked grains, there was an increase in bioavailability of zinc and, in the case of kañiwa, also in iron and calcium bioavailability. In all cases, the contents of total and insoluble dietary fiber decreased during the extrusion process. At the same time, the content of soluble dietary fiber increased. The content of total phenolics, phytic acid and the antioxidant activity decreased in kiwicha varieties during the extrusion process. In the case of quinoa, the content of total phenolic compounds and the radical scavenging activity increased during the extrusion process in all varieties. Taken together, the studies presented here demonstrate that the Andean indigenous crops have excellent potential as sources of minerals, flavonoids and dietary fiber. Further studies should be conducted to characterize the phenolic compound and antioxidant composition in processed grains and end products. Quinoa, kañiwa and kiwicha grains are consumed widely in Andean countries but they also have a significant, worldwide potential as a new cultivated crop species and as an imported commodity from South America. Their inclusion in the diet has the potential to improve the intake of minerals and health-promoting bioactive compounds. They may also be interesting raw materials for special dietary foods and functional foods offering natural sources of specific health-promoting components.

An Infant with Food Allergy and Eczema in the Family – The Mental and Economic Burden of Caring

Allergic diseases including food allergy and eczema in an infant in combination with the everyday activities of caring for a family will pose challenges to parents. Only fragments of these challenges are revealed to health care professionals. Families have varying mental, social and economic resources to help them care for an allergic infant, and all such resources are important in determining how families succeed in meeting these challenges and the quality of the infant’s care. This study evaluated the whole burden to the family caused by an infant's allergic disease during the first 24 months of life. As the primary caregiver during this period is usually the mother, her perspective was considered important. Ecocultural theory, which considers families as capable of modifying the positive and negative forces facing them, was taken as the frame of reference. Data were collected as part of an ongoing prospective mother-infant study, and the methods included severity scoring of atopic dermatitis, dietary records, health-related quality of life measurements and assessments of the use of health care services and medications for treating the infant’s eczema, food allergy and asthma. Interviews with mothers were analysed by deductive content analysis on the basis of ecocultural theory and the family empowerment model. The theme “Living an ordinary family life” guided the organization of family activities essential for treating the infant's food allergy and eczema. These activities were sources of both strain and support for the mothers, the allergy-related supporting factors being the mother’s own knowledge of the allergy, hopes for an improvement in the infant’s condition, social support and work. An infant’s food allergy at the age of one year caused considerable strain for the mother in cases where the introduction of new foods into the child’s diet was delayed. This delay was still causing the mother additional strain when the child was 24 months of age. The infants waking at night at the ages of 12 and 24 months because of itching related to eczema caused strain for the mothers. The infants’ health-related quality of life was impaired at ages of 6 and 12 months compared with healthy infants. The principal reasons for impairments were itching, scratching and sleep disturbances at 6 and 12 months and treatment difficulties at 6 months. Problems with getting to sleep were reported at all stages irrespective of eczema and were also present in healthy infants. The economic impact of the treatment of allergic diseases on families during the first 24 months was 131 EUR (2006 value) in cases of eczema and 525 EUR in cases of food allergy. From the societal perspective, the costs of food allergy were a median of 3183 EUR (range 628–11 560 EUR) and of eczema a median of 275 EUR (range 94–1306 EUR). These large variations in costs in food allergy and eczema indicate that disease varies greatly . In conclusion, food allergy and eczema cause extra activities and costs to families which arrange these disease-related activities in such a way that they support the leading family theme “Living an ordinary family life”. Health care professionals should consider this thematic character of family life and disease-related activities in order to ensure that new treatments are sustainable, meaningful and tailored to daily activities. In addition, those mothers who are experiencing difficulties with food allergic infants or infants with eczema should be recognized early and provided with individual encouragement and support from health clinics. In the light of the present results, early detection of symptoms and effective parental guidance can contribute to the well-being and health-related quality of life of the child and family.

Climate driven changes in temperature, pH and food quality : effects on copepod reproduction

Increased emissions of greenhouse gases into the atmosphere are causing an anthropogenic climate change. The resulting global warming challenges the ability of organisms to adapt to the new temperature conditions. However, warming is not the only major threat. In marine environments, dissolution of carbon dioxide from the atmosphere causes a decrease in surface water pH, the so called ocean acidification. The temperature and acidification effects can interact, and create even larger problems for the marine flora and fauna than either of the effects would cause alone. I have used Baltic calanoid copepods (crustacean zooplankton) as my research object and studied their growth and stress responses using climate predictions projected for the next century. I have studied both direct temperature and pH effects on copepods, and indirect effects via their food: the changing phytoplankton spring bloom composition and toxic cyanobacterium. The main aims of my thesis were: 1) to find out how warming and acidification combined with a toxic cyanobacterium affect copepod reproductive success (egg production, egg viability, egg hatching success, offspring development) and oxidative balance (antioxidant capacity, oxidative damage), and 2) to reveal the possible food quality effects of spring phytoplankton bloom composition dominated by diatoms or dinoflagellates on reproducing copepods (egg production, egg hatching, RNA:DNA ratio). The two copepod genera used, Acartia sp. and Eurytemora affinis are the dominating mesozooplankton taxa (0.2 – 2 mm) in my study area the Gulf of Finland. The 20°C temperature seems to be within the tolerance limits of Acartia spp., because copepods can adapt to the temperature phenotypically by adjusting their body size. Copepods are also able to tolerate a pH decrease of 0.4 from present values, but the combination of warm water and decreased pH causes problems for them. In my studies, the copepod oxidative balance was negatively influenced by the interaction of these two environmental factors, and egg and nauplii production were lower at 20°C and lower pH, than at 20°C and ambient pH. However, presence of toxic cyanobacterium Nodularia spumigena improved the copepod oxidative balance and helped to resist the environmental stress, in question. In addition, adaptive maternal effects seem to be an important adaptation mechanism in a changing environment, but it depends on the condition of the female copepod and her diet how much she can invest in her offspring. I did not find systematic food quality difference between diatoms and dinoflagellates. There are both good and bad diatom and dinoflagellate species. Instead, the dominating species in the phytoplankton bloom composition has a central role in determining the food quality, although copepods aim at obtaining as a balanced diet as possible by foraging on several species. If the dominating species is of poor quality it can cause stress when ingested, or lead to non-optimal foraging if rejected. My thesis demonstrates that climate change induced water temperature and pH changes can cause problems to Baltic Sea copepod communities. However, their resilience depends substantially on their diet, and therefore the response of phytoplankton to the environmental changes. As copepods are an important link in pelagic food webs, their future success can have far reaching consequences, for example on fish stocks.

Exploring the role and transformative potential of human rights in development practice and food security : case study from Malawi

Avhandlingen är en analys av den roll som mänskliga rättigheter spelar i utvecklingssamarbete i allmänhet och tre matsäkerhetsprojekt i Malawi i synnerhet. Författaren undersöker huruvida mänskliga rättigheter kan bidra till samhälleliga förändringsprocesser. Undersökningen har en diskursiv syn på mänskliga rättigheter; rättigheter ses som sociala konstruktioner skapade av människor, konstruktioner som förändras i takt med att aktörerna ger dem ny mening. Människorättsbaserade utvecklingsstrategier riktar uppmärksamheten mot olika aktörers skyldigheter samt vikten av att mänskliga rättigheter inte kränks genom utvecklingspolitiska beslut. En analys som utgår från mänskliga rättigheter kan leda till att nya frågor lyfts fram: vem har skyldigheter, vem har rättigheter, och varför förverkligas inte dessa? Fokus flyttas till hur politiska, ekonomiska och juridiska strukturer kan förändras så att de främjar mänskliga rättigheter. Författaren använder empiriskt material från Malawi för att visa vilken roll mänskliga rättigheter och så kallade människorättsprinciper spelar inom tre projekt: (1) ett mathjälpsprojekt; (2) ett rättighetsbaserat projekt med fokus på att stärka strategier för livsuppehälle; (3) ett juridiskt projekt inom ramen för vilket man skapat ett lagförslag om rätten till föda. Analysen visar att det rättighetsbaserade projektet strävade efter den mest djupgående samhälleliga förändringen. Människorättsprinciperna ansvarighet och deltagande handlade inte endast om verksamheten inom projektet utan man strävade även efter att stärka dessa principer mellan medborgare och myndigheter. Rättigheter, som ett sätt att tala, tänka och handla, inte som abstrakta juridiska normer, påverkade de lokala aktörernas sätt att kräva bl.a. tjänster av lokala myndigheter. Teoretiskt kan man säga att det rättighetsbaserade projektet representerar ett aktörsperspektiv på mänskliga rättigheter där aktörernas egna uppfattningar om vad de är berättigade till samt krav på myndigheters ansvar formade vilken mening rättigheterna kom att få.