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Tämän tutkielman tavoitteena on uutisten kautta tehty ruokatrendin kuvaaminen ja sen kehityksen seuranta. Esimerkkitapaukseksi on otettu vähähiilihydraattinen ruokavalio karppaus ja sen uutisointi valituissa medioissa. Tutkimuksessa etsitään vastausta tutkimuskysymykseen, miten nämä uutiset käsittelevät ruokatrendiä sen elinkaaren aikana. Alaongelmiksi määriteltiin, uutisten vaikutus ruokatrendiin ja miksi yritysten olisi niin tärkeä yrittää tunnistaa ruokatrendejä. Näihin kolmeen tutkimuskysymykseen saatiin tutkielman teorian ja aineiston avulla vastaukset. Teoriassa avattiin trendin ja median käsitteitä. Aluksi selvitettiin, mikä on trendi ja miten se leviää ympäristössään. Tämän jälkeen siirryttiin avaamaan sitä, miksi trendien ennakointi on niin tärkeää liiketoiminnan kannalta. Teorian media osuudessa pyrittiin saamaan selville, miten media toimii mielipiteiden muokkaajana ja vaikuttaa toiminnallaan trendeihin. Tutkimuksessa menetelmänä käytettiin sisällönanalyysiä, jonka avulla aineisto ensin kvantifioitiin. Tämän jälkeen aineisto käsiteltiin myös kvalitatiivisesti, jotta se saatiin hyödynnettyä mahdollisimman hyvin. Aineistona toimi Helsingin Sanomien ja YLE:n Internet-sivuilla tapahtunut uutisointi vuosina 2010–2013. Aineistoon kertyi 168 kappaletta uutisia karppauksesta ja siihen liittyen. Tutkimuksen perusteella voidaankin todeta, että karppaus on ainakin enemmän kuin villitys, koska se ehti vaikuttaa niin moneen ihmiseen ja niin laajasti ympäristöönsä tämän neljän seuranta vuotensa aikana. Teoriaosassa villityksen ja trendin eroksi määritellään se, että villitys vaikuttaa vain muutamiin ihmisiin lyhyessä ajassa, kun trendi vaikuttaa moniin ihmisiin pidemmällä aikavälillä. Voidaan myös todeta, että tutkimuksen yksi tärkeimmistä tuloksista oli se huomio, kuinka laaja-alainen ja vahva trendi karppaus loppujen lopuksi oli. Aineiston uutisista välittyi hyvin se, miten trendi ehti vaikuttaa elinkaarensa aikana ympäristöönsä varsin laajasti. Karppaus ehti vaikuttaa niin talouteen, kansanterveyteen ja ympäristöön. Tutkimuksessa saatiin myös tukea ennakko-oletukselle trendien ennustamisen ja seuraamisen vaikeudesta, mutta myös sen tärkeydestä yritykselle. Yritysten olisi hyvin tärkeä yrittää ennakoida tai edes puskuroida tulevia trendejä. Yllätetyksi tuleminen on hyvin vaarallista. Trendien oikea aikainen valjastaminen voi olla yritykselle hyvin menestyksekästä ja siihen tulisi pyrkiä.

Humans all over the world are selecting food items from a larger pool of potentially edible foods and are creating prohibitions and preferences for certain foods. These are called food beliefs and they are an important part of the local culture. Reasoning to them often lies in health or social respect. Many food beliefs still exist in Africa and pregnant and breastfeeding women and children are often the target of these beliefs. Under the suboptimal nutritional status or food insecurity the possible food beliefs might considerably affect the nutritional status and health of these vulnerable groups. Malnutrition is still a major problem in Africa and other developing countries. The aim of this thesis was to study whether and what types of food beliefs concerning pregnant and breastfeeding women can be found in the rural area of the Zambezia province, Mozambique. Furthermore, the aim was to evaluate their possible significance on nutritional status. Five group interviews in three villages and 10 individual interviews in two villages were done. Interviewees were women of 12 to 78 years of age and all together 27 women were interviewed. Interpretation, sensitivity of the topic and the inexperience of the interviewer caused challenges in conducting the interviews. Because of this the method was altered and changed from group interview to individual interview during the study. Food beliefs differed between villages and within villages but some common characteristics can be found. There are several food beliefs concerning pregnant and breastfeeding women in the study area. Pregnant women were advised not to eat protein rich foods such meat and fish but were recommended to eat vegetables, fruits and cereal foods during pregnancy. Eggs were both recommended and forbidden during pregnancy. In addition, there was an intentional habit for pregnant women to eat less cassava porridge or less food in general („eating down?). During breastfeeding nothing was forbidden in general but coconut and vegetables were recommended. Most of the reasonings were related to the health of a mother and a child. The reasonings can be divided into the following groups: enhances breast milk production, causes stomach pain, maintains fitness and prevents stomach growth, mother will be strong and healthy and she?ll get vitamins, the child?s appearance changes, child will be strong and healthy, child?s behaviour changes, causes miscarriage, causes easy or difficult delivery. Food beliefs were partly mixed with education from health authorities. Almost all women said that they do follow these beliefs. Few women expressed their concerns about following the beliefs on recommended foods since food availability makes it sometimes difficult. Food belief that forbids good protein sources from pregnant women can increase the risk of protein deficiency. Eating down increases the risk of having not enough energy during pregnancy. The recommended foods are mainly nutritious and likely promote health. It can be stated that when starting a research in a foreign culture, it is necessary to have a flexible research method. It is be very important that the method can be adjusted during the study. The conclusion of this thesis was that individual interviews would have been the most suitable method when studying food beliefs in this area. Individual interviews should have only one interviewer, interviewee and interpreter if needed. All should be the same sex and the age group. From the health and nutrition viewpoint it is vital to be aware of the food beliefs in the society under investigation and to study these specifically in the area because these can vary markedly even in the same village or community.

Tausta ja tavoitteet: Maailmalla on tehty vasta muutamia tutkimuksia, joissa on hyödynnetty kattavaa terveys- ja elämäntapakartoitusta. Vielä ei ole tiedossa, auttaako monipuolinen henkilökohtainen tieto omasta terveydestä parantamaan ruokavaliota, jotta se noudattaisi paremmin suomalaisia ravitsemussuosituksia. Aiemmat tutkimukset ovat osoittaneet, että yksilöllinen hyvinvointivalmennus parantaa ruokavalion laatua kuvaavien ruokavalioindeksien (Healthy Eating index ja Mediterranean Diet) pisteitä, vähentää tyydyttyneiden rasvojen saantia ja punaisen lihan käyttöä sekä parantaa serumin D-vitamiiniarvoja. Tämä tutkielma oli osa Digital Health Revolution (DHR) -tutkimusta ja tavoitteena oli kuvata tutkimukseen osallistuneiden ihmisten ruokavalion laatua ja niiden muutoksia sekä tutkia, oliko tutkimuksen aikana annettu tieto henkilökohtaisista terveysriskeistä yhteydessä ruokavaliomuutoksiin. Aineisto ja menetelmät: DHR-tutkimus kesti 16 kuukautta ja se sisälsi viisi tutkimuskäyntiä. Tutkielmassa käytettiin aineistoa 96 tutkittavalta, joista 69 % oli naisia ja 75 % korkeasti koulutettuja. Ruokavalion tutkimisessa hyödynnettiin DHR-tutkimuksen ruoankäyttökyselyä ja terveellisen ruoankäytön ruokavalioindeksiä (Healthy Food Intake Index, HFII), joka koostui yhdeksästä ruokakomponentista. Indeksin maksimipisteet olivat 15. Pisteytys perustui pohjoismaisiin ja suomalaisiin ravitsemussuosituksiin sekä ruokien käyttötiheyden kolmanneksiin tai mediaaniin. Terveysriskien ja ruokavaliomuutosten yhteyden selvittämiseksi tutkittavat jaettiin kahteen ryhmään. Toiseen ryhmään luokiteltiin ne, joilla oli toisella tutkimuskäynnillä vähintään yksi viidestä terveysriskistä (painoindeksi ≥30kg/m², vyötärönympärys ≥80cm, naiset tai ≥94cm, miehet, paastoglukoosi ≥6,1 mmol/l, kokonaiskolesteroli/HDL-kol.>4 mmol/l, verenpaine ≥130/85 mmHg, n = 47) ja toiseen ne, joilla ei ollut näistä yhtäkään (n = 41). Tulokset: Indeksipisteiden keskiarvoissa ei havaittu muutoksia tutkimuksen aikana. Heikkolaatuisen ruokavalion omaavien (2–5 p, n = 17) indeksipisteiden keskiarvo kuitenkin parani tutkimuksen aikana 1,2 (± 2,0, p = 0,009) pistettä ja paremman ruokavalion laadun omaavien (11–13 p, n = 16) pisteet huononivat 1,3 (± 1,8, p = 0,02) pistettä. Yksilötasolla havaittiin suuriakin muutoksia indeksipisteissä. Neljäsosalla tutkittavista tulos parantui ja viidesosalla heikentyi vähintään kahdella pisteellä. Tieto terveysriskeistä vaikutti myönteisesti ruokavalion laatuun lyhyellä (3,5 kk) aikavälillä mutta ei pitkällä (10,5 kk) aikavälillä. Johtopäätökset: Työssä ei havaittu systemaattista ruokavalion laadun parantumista. Henkilökohtaiset terveysriskit kuitenkin olivat yhteydessä indeksipisteiden parantumiseen lyhyellä aikavälillä. Yksilötasolla useammalla kuin kolmella neljästä pisteiden muutokset olivat vaatimattomia ja niiden käytännön merkitys ruokavalion laadun kannalta voi olla vähäinen. Puutteet ruokavalioindeksissä, kontrolliryhmän puute ja rajallinen aineiston koko heikentävät yleistettävyyttä ja tulosten merkitystä.

Fosfori on sioille välttämätön alkuaine, jota sika käyttää moniin elimistön toimintoihin kuten kasvuun ja lisääntymiseen. Kasveissa fosfori on sellaisessa muodossa, etteivät yksimahaiset eläimet pysty sitä kunnolla hyödyntämään ja sulamaton fosfori erittyy sian sontaan. Sian ulosteessa fosfori on merkittävin ympäristölle haitallinen aine ja epäorgaaninen fosfori on kolmanneksi kallein komponentti sikojen ruokinnassa. Fytaasientsyymin avulla on mahdollista saada rehujen sisältämä fosfori paremmin sikojen käyttöön ja näin alentaa ruokinnan lisätyn ja sontaan eritetyn fosforin määrää. Tämän tutkielman tavoitteena oli optimoida sikojen erittämän fosforin määrää alentamatta sikojen tuotantotuloksia lisäämällä rehujen sisältämän fytaasientsyymin määrää ja alentamalla fosforin määrää. Tutkimus tehtiin yhteistyössä Luonnonvarakeskuksen ja A-Tuottajien kanssa lihasikatilalla Nurmossa 19.11.2019–21.2.2020. Kyseessä oli satunnaistettu koe, jossa havaintoyksikön muodostavat yhden ruokintaventtiilin siat (24sikaa / venttiili). Kokeessa oli 504 lihasikaa, jotka jaettiin sukupuolen mukaan karsinoihin (leikot / imisät). Käytössä oli kaksi rehuseosta, kontrollirehu ja koerehu, jossa oli vähennetty fosforin määrää ja lisätty fytaasin määrä. Koe jaettiin kahteen jaksoon, ensimmäisen jakson aikana siat olivat alle 55 kilogramman (kg) painoisia ja toisen jakson aikana yli 55 kg:n painoisia. Koeasetelma oli 2x2 faktoriaalinen, jossa vakiomuuttujat olivat rehun koostumus ja sikojen sukupuoli. Tutkimuksessa tarkasteltiin käytetyn rehun ja sukupuolen vaikutusta sikojen tuotanto- ja teurastuloksiin sekä eritetyn fosforin määrään. Rehujen fytaasiaktiivisuuden määrä koe- ja kontrollirehun välillä erosi vähemmän kuin kokeessa oli suunniteltu, mutta siitä huolimatta tulokset eivät olleet poikkeavia aikaisempiin tutkimuksiin verrattuna. Koerehu vähensi sikojen sontaan erittämän fosforin määrää merkitsevästi ensimmäisellä ruokintajaksolla, sikojen ollessa alle 55 kg:n painoisia. Koerehulla ei havaittu olevan merkitsevää vaikutusta muihin sikojen tuotantotuloksiin, kuin rehuyksiköiden syöntiin sikojen ollessa yli 55 kg:n painoisia. Leikoilla huomattiin olevan suurempi kuiva-aineen ja rehuyksiköiden syönti sikojen ollessa yli 55 kg:n painoisia. Imisöiden rehuhyötysuhde oli leikkoja parempi sikojen ollessa yli 55 kg:n painoisia. Leikot kasvoivat imisöitä paremmin alle 55 kg:n painoisena ja painoivat keskimäärin enemmän 105- päivän ikäisenä. Sikojen teuraspaino oli suurempi koe- kuin kontrollirehua käytettäessä, mutta muuten käytetyllä rehulla ei ollut vaikutusta sikojen teurastuloksiin. Imisöiden lihaprosentti oli suurempi kuin leikkojen. Tämän ja aiempien tutkimusten tulosten perusteella fytaasin käyttömäärää voidaan nostaa yli nykyisen standarditason lihasikojen alkukasvatuksessa. Alennettu fosforin määrä saatiin korvattua lisäämällä rehuihin fytaasia, joka tehosti fosforin hyväksikäyttöä niin paljon ettei sikojen tuotanto- tai teurastulokset alentuneet. Samalla myös sontaan erittyneen fosforin määrää saatiin pienennettyä, kun fytaasin määrää rehuissa lisättiin.

The objective of this study was to investigate the associations between nutritional factors and the incidence of peripheral caries and other oral diseases in Finnish horses. Peripheral caries was chosen as the main subject of this study because of its wide prevalence in horse population. Peripheral caries is also a risk factor for other oral diseases, and it is thought to express well the effects of feeding to teeth. The aim of this study was also to find out how the Finnish horse population is fed. The study was carried out as questionnaire at Porvoon Hevosklinikka. Horse owners filled the questionnaire according to the information from oral exam done by veterinarians. Oral exams were carried out by two Specialists in Veterinary Medicine, Equine Diseases. Of the 94 horses included in this study, 79% (n=74) had been diagnosed with peripheral caries by a veterinarian. The incidence of peripheral caries was significantly associated with breed and use of hay net. All (n=12) of the warmblood trotters in this study had peripheral caries. Most of the horses (95 %, n=22) that ate their roughage from hay net had peripheral caries. Only 35 % of the horse owners had access to feed analysis of roughages fed to their horses. As much as 85 % of the horses whose owners did not have access to feed analysis had peripheral caries. Some symptoms in eating behavior and riding or driving behavior have been connected to pain at cheek teeth. In this study 37 % of owners reported that horses did not have any of these symptoms. Most (83 %, n=29) of these horses however had peripheral caries. Because of the small sampling and reference group more study of this subject is needed. According to this study most of the Finnish horse owners do not have feed analysis of their roughage and therefore they cannot plan the feeding based on the analysis. Despite this almost all (96%) of the horses in this study had their feeding supplemented with concentrates.

Background: Foodservices have a significant role in the Finnish food culture. For many Finnish people the food produced by the mass catering industry is the only hot meal for the day. Foodservices are present throughout the life from kindergarten children to the elderly people at nursing homes. But working career is the longest singular time period in life in which foodservices are present. Every day over one third of Finnish employees choose to have their lunch at a staff canteen. The role of worksite eating in sustaining public health is important. The food served at staff canteens should be healthy, diverse and nutritionally well composed. Nutrition quality is a term that describes how well the nutrition guidelines are met in the meals served by foodservices. Aim: The aim of the research was to assess the nutrition quality of the meals served by staff canteens and eaten by the employees. Data and methods: The data of the research consisted of menus for two weeks by a foodservice company`s three restaurants, photos of employees’ meals (n=350) and questionnaires, observations at the staff canteens and the self-evaluations made by the restaurant managers. The evaluation of nutritional quality of the served meals was based on two nutrition quality criteria: Heart Symbol and Arkilounaskriteerit. Arkilounaskriteerit is a questionnaire filled by the restaurant manager. Arkilounaskriteerit is a tool that answers the question whether or not the diner has a chance to eat according to national food recommendations at the staff canteen. The criteria of the Heart Symbol are more specific than Arkilounaskriteerit with regards to the nutrition quality of the meal. The Heart Symbol criteria includes the nutrient level of the meal, it has criteria for the amounts of fat and saturated fat but also for the amounts of salt and nutrition fiber. On the basis of the photos of the employees’ meals and questionnaires I assessed how the Heart Symbol criteria were met and to what extent it was composed by a plate model. Using the plate model I assessed from the meals the proportions of vegetables, sources of protein and carbohydrates, and also what kind of a drink and how many glasses they had, did they have salad dressing, bread, bread spread or a dessert. Both Arkilounaskriteerit and Heart Symbol criteria include a statement that they must inform customers about the healthier food choices. This information criteria were assessed at the staff canteens. Results: The four fields of Arkilounaskriteerit were fulfilled “well” or “moderately”. The menus had a combined number of 224 food items (155 sources of proteins, 46 sources of carbohydrates and 26 other side dishes), of which 45 items (20 %) were marked with a Heart Symbol. After analysing the food items it was discovered that the criteria of the Heart Symbol were fulfilled by 74 food items (33 %). The Heart Symbol criteria were met by 31 % of the sources of protein, 37 % of the sources of carbohydrate and by 9 % of other side dishes. In those cases where the Heart Symbol criteria were not met the reason was most commonly in the amount of salt (over 40 % had salt above the criteria limit). In 10 % of the employees’ meals there were vegetables, sources of protein and carbohydrates according to the plate model. The meals were composed almost by the plate model. On average plates had 30 % source of protein, 20 % source of carbohydrate and 50 % vegetables. Typically the meal also contained salad dressing, one glass of water but no bread or dessert. Conclusions: Given the criteria of the Heart Symbol and the drive of the company, the nutrition quality of the served food items was low in most cases. Two thirds of the food items did not meet the criteria of the Heart Symbol, even though the company informs that they have nutrition guidelines in use. To enhance the nutritional quality of the meals the diners should make only minor changes in the proportions of sources of protein and carbohydrate. According to the criteria used in this research the staff canteens should have a plate model on display (criteria of informing the client). Regardless of the criteria this was not the case. The nutrition quality of food at staff canteens should be researched on a wider spectrum to have a deeper understanding of the subject. Research should be done all over Finland in several different foodservice companies - in this way it would be possible through staff canteens to tackle the greatest challenges of the Finns’ nutrition: too much salt and too little vegetables in their diets.

In order to increase protein self-sufficiency and food production, it is necessary to study new protein feeds. Faba bean (Vicia faba) is a nitrogen-fixing plant, and thereby a good choice for versatile rotation of crops. Faba beans contain less crude protein and considerably more starch than rapeseed meal. Most of the faba bean protein degrades in rumen and it contains less methionine than rapeseed meal protein. Microalgae contain plenty of crude protein and their production requires less surface area than cultivation of field crops. Microalgae can also be grown in harsh climate conditions. However, microalgae have, in some of the earlier studies, reduced palatability of the diet. Aim of this Master’s Thesis was to compare rapeseed meal, faba bean seeds and Spirulina microalgae effects on feed intake and milk production of dairy cows. Hypothesis were decreased feed intake when Spirulina was added to the diet; lower milk production with faba bean diet than with rapeseed diet; and increased milk production when a part of faba bean protein was replaced with Spirulina protein. The study was conducted at Viikki research farm at Helsinki during the spring of 2015. Eight multiparous ayrshire dairy cows were used. At the beginning of the study, on average 113 days were passed since calving of the cows. The study design was a replicated 4 x 4 Latin square. Cows of the other square were rumen fistulated. Treatments (rapeseed, rapeseed + Spirulina, faba bean, faba bean + Spirulina) were isonitrogenous. In microalgae treatments protein from Spirulina was used to substitute half of the protein from rapeseed or faba bean. Total mixed ration (TMR) included in addition to protein feeds grass silage, barley, molassed sugar beet pulp and vitamins and minerals. Cows received TMR ad libitum. There were no differences in dry matter intake (DMI) between rapeseed and faba bean treatments. According to the hypothesis, DMI was decreased with Spirulina diets. Hypothesis regarding milk production were also realised. Milk, energy-corrected milk, fat, protein and lactose yields were lower with faba bean than with rapeseed treatments. Adding Spirulina to diet increased milk yield in faba bean treatment, but decreased it in rapeseed treatment. Adding Spirulina to diet did not affect energy-corrected milk yield significantly. Spirulina did not affect fat yields, and it lowered the protein and lactose yields in rapeseed treatment, and increased them in faba bean treatment. Based on the findings of the study, faba bean and Spirulina are inferior protein feeds compared to rapeseed meal in grass silage and grain based diets. Faba bean protein’s high rumen degradability and low methionine concentration probably limit milk production. Spirulina and faba bean combined meet dairy cow’s amino acid needs better than faba bean alone. However, Spirulina’s negative impact on DMI may restrict its usage as a protein feed for dairy cows.

Agriculture is responsible of 60 % of phosphorus load in water systems. The phosphorus load of milk production can be influenced by dietary phosphorus concentration. Rapeseed (Brassica rapa L. ssp. Oleifera) meals and cakes are commonly used as protein supplement for dairy cows due to their good milk production response. However, the concentration of phosphorus is high in rapeseed meal. Excessive phosphorus is mainly excreted through faeces, which is why dietary phosphorus concentration should be kept moderate. The phosphorus concentration of faba beans (Vicia faba L.) is lower than that of rapeseed meal, but milk production response of faba beans is lower likely due to its lower methionine concentration. Milk is significant phosphorus sink, so it is important simultaneously to maintain milk production while decreasing the dietary phosphorus concentration. The aim of this master’s thesis is to compare the effects of rapeseed meal, faba beans and Spirulina platensis microalgae on the phosphorus utilisation in milk production. The experiment was conducted at Viikki Research farm in University of Helsinki during spring 2015. In the experiment, the effects of different protein supplements on the dry matter (DM) and phosphorus intake of dairy cows, milk production, phosphorus concentration of milk, faeces and urine, and phosphorus utilisation were compared. Eight multiparous Finnish Ayrshire cows were used in 4x4 Latin square study with four dietary treatments and four 21-d periods. The arrangement of treatments was 2x2 factorial. Basal protein supplements were either rapeseed meal or rolled faba beans, of whose protein 0 % or 50 % were substituted by spirulina. The diets were isonitrogenous in regards to nitrogen supply from protein feed. Cows had ad libitum access to total mixed ratio (TMR) consisting of experimental protein feed, grass silage, barley, sugar beet pulp and mineral-vitamin mixture. The roughage:concentrate ratio was 55:45 in DM in all experimental TMR’s. The phosphorus concentration of the diets was 3,93 g/kg DM (rapeseed meal), 3,90 g/kg DM (rapeseed meal + spirulina), 3,75 g/kg DM (faba beans) and 3,76 g/kg DM (faba beans + spirulina). The DM intake did not differ between faba beans and rapeseed meal, but was decreased when basal protein feed was substituted by spirulina. The substitution of basal protein feed by spirulina decreased milk yield on rapeseed based diets but increased it on faba bean based diets. Phosphorus intake was higher and the phosphorus concentration of faeces tended to be higher on rapeseed than on faba bean based diets. Phosphorus intake was decreased by the substitution of basal protein feed by spirulina but this had no effect on phosphorus concentration of faeces. Phosphorus utilisation in milk production was equally effective with rapeseed and faba bean based diets, and tended to increase when basal protein feed was substituted by spirulina. Based on this study, the milk production response of faba beans and spirulina is lower than that of rapeseed meal. The diet including both faba beans and spirulina might be good alternative in terms of phosphorus utili-sation, since on this diet milk yield was higher than on the diet having faba beans as sole protein feed, and the phosphorus concentration of faeces was lower than on rapeseed based diets. The partial substitution of basal protein feed by spirulina increased the efficiency of phosphorus utilisation in milk production. This indicates that faba beans have potential to increase the efficiency of phosphorus utilisation in milk production when the amino acid composition of faba beans are balanced with feeds rich in methionine. Phosphorus utilisation can also be increased by partial substitution of rapeseed meal by spirulina if palatability and subsequently the milk production response of spirulina can be improved.

The literature review examined structures and functionalities of two major canola proteins, cruciferin and napin. In addition, fundamental functional properties of proteins and the impact of high intensity ultrasound on functionality of other proteins were reviewed. Ultrasound treatment has been successfully used to improve several functional properties of other proteins such as soy, pea and egg white proteins. However, research on high intensity ultrasound treatment for improving canola protein functionality is limited. The aim of the experimental part was to improve solubility, rheological and emulsification properties of canola proteins using high intensity (20 kHz) ultrasound. The effects of ultrasound treatment on protein structures were also examined. Canola samples were first preheated (95 °C, 5 min) and then treated with ultrasound at different power intensity levels (200 and 400 W) and durations (10 and 30 min). Albumin fractions were obtained by water extraction (pH 7.3) and NaCl extraction (1 M, pH 6.3) was used to obtain globulin fractions. The soluble protein concentration was determined using DC Protein Assay (Bio-Rad, USA), free sulfhydryl content was measured according to Ellman’s procedure and electrophoresis (SDS-PAGE) was performed for the determination of protein composition. Emulsifying ability, creaming index, average particle size, viscosity, storage modulus (G’) and loss modulus (G’’) were determined from the heat-induced emulsion gels. Solubility and emulsion stability of ultrasound treated canola samples were improved compared to control samples. In addition, ultrasound treatment reduced the average particle size. However, the electrophoretic profiles of the control and ultrasound treated canola protein samples did not differ significantly. Based on the rheological measurements, all the emulsion gels were shear thinning and indicated elastic properties (G’>G’’). These results suggest that high intensity ultrasound treatment modified the structures of canola proteins enabling increased molecular interaction and enhancing particularly emulsion gel stability.

The literature part of the study dealt with frying methods, frying fats and oils, chemical and physical changes of frying fats and oils during the frying and analyse methods of frying fats and oils. The aim of the experimental part was to study changes in rapeseed oil quality during continuous frying process during three different frying periods. Especially the effect of day without production during the frying period was studied. Samples, frying oils, were taken every day during the different frying periods. In period one and two there was one day without production. Oils were stored in storage tanks during that time. In third period, there was production on every day. All samples were inspected for colour, odour, viscosity and clearness by visual methods. Also viscosity by rotation viscometer, smoking point, free fatty acids by titration method, fatty acid content and water content of samples was analysed. Based on sensory evaluation, the quality of oil deteriorated over thedays of use. Colour was darker, viscosity was higher and off-odours were sensed. Instrumental analyses indicate same kind of changes; viscosity and free fatty acid were increased and smoking point and amount of unsaturated fatty acid were decreased while frying time was increasing. In literature, also same changes were mentioned. There was changes in fatty acid content during the frying periods. More fatty acids characteristic to meat was detected in oils at the end of period than in fresh oils. Based on these results, oil quality remained acceptable in everyday use for a typical frying period of one week. Difference between fresh oil and used oils was clear but still acceptable. The amount of free fatty acids, and the level of viscosity and smoking points were under the limits applied in Finland. The day without production deteriorated oils quality substantially Reducing the amount of oil in process and having shorter frying periods or more efficient filtering of oils can help to keep the quality of frying oil better.