Skip to main content
Login | Suomeksi | På svenska | In English

Browsing by Subject "oat"

Sort by: Order: Results:

  • Manngård, Jessica (2024)
    Whole grain oats have a high nutritional value and a favorable taste, making oats a valid option to enhance the nutritional properties of food products. Due to the absence of gluten, baking with oat flour can be challenging but lactic acid bacteria fermentation can provide the needed functional activities and modify the sensory properties. The aim of this study was to find lactic acid bacteria (LAB) and yeast starter cultures suitable for oat flour fermentation and define their main metabolic profile. The sourdoughs were prepared with whole grain oat flour and water. Some of these also contained sprouted grain oat and fructose or sucrose to facilitate fermentation. Strains from species Lactiplantibacillus plantarum, Levilactobacillus brevis, and Saccharomyces cerevisiae were used as starters. Microbial enumeration was carried out and acidification was studied by measuring pH and total titratable acidity; organic acid content was analysed with high performance liquid chromatography. The results indicate that there are benefits to using LAB and yeast in consortium to produce oat sourdough, in that they acidify the dough and produce organic acids. The addition of sprouted oat was beneficial, allowing higher acidification and higher organic acid production. Fructose successfully allowed to increase the content of acetic acid. Sensory and baking tests are needed to draw final conclusions on the flavor of the bread.
  • Rekola, Kristiina (2015)
    Chemical composition of oats and its suitability for baking were reviewed in the literature part. The special features of baking without gluten and possibilities to increase the quality of gluten-free bread were also discussed. The aim of the experimental research was to develop high protein gluten-free oat-based bread. The effect of different protein concentration on structural, textural and sensory properties of gluten-free oat bread was studied. Also the effect of processing method on bread quality was studied by using sourdough technology and straight dough technology. Gluten-free oat bread recipe and baking protocol as well as sourdough fermentation conditions were optimized on the basis of preliminary trials. Oat-based breads with varying protein content were baked by using straight dough and sourdough technologies. Reference sample was oat-based bread without added protein. Specific volume, moisture content, texture profile analysis (crumb hardness, chewiness and resilience) and starch retrogradation of gluten-free breads were analysed. For shelf life measurements, breads were stored in plastic bags at room temperature from 1 to 3 days. Sensory profile of bread samples were evaluated on the day of baking by a trained panel. Descriptive analysis method was used. Palatable high protein gluten-free oat-based bread was obtained in this study. Increasing amount of protein improved the crumb structure and shelf life of gluten-free breads. All of the protein supplemented breads had agreeable sensory profile. Sourdough did not further improve the quality of high protein gluten-free bread except for increased aroma intensity. Oats and its fractions can be successfully applied as an ingredient for gluten-free baking to enhance the nutritional quality.
  • Karhu, Simo (2024)
    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.
  • Turkki, Tuomas (2020)
    Constant increase in protein consumption is global trend and can be seen in consumer behavior of Finnish markets. Consumers are interested in replacing meat proteins with plant proteins, and therefore, it is important to develop locally grown-domestic products and invest in local crop research. Due to this, the current study focuses on the domestic vegetable protein (faba bean and oat) texturing by extrusion cooking and on their functionality when included in burgers. The literature section presents an overview of previous studies on extrusion of vegetable proteins and the functionality of textured vegetable proteins (TVP). In the experimental work the research materials were faba bean protein concentrate and oat concentrate with high β-glucan content. The flour concentrates were texturized with high-moisture extrusion, in different mixtures. Mixtures were prepared in the ratio of: 3:1 (FO) and 1:3 (OF) and soy protein concentrate (S) was used as a reference sample. Moisture content and water absorption capability of TVP samples were measured instrumentally. TVPs were later on applied to develop burgers based on a mixture of meat and vegetable sources. Burgers were prepared for instrumental analysis with seven different recipes, where TVP inclusion, water addition and meat content varied. TVP was included in three different percentages: 0, 25 and 50% and water was added in 0, 12.5 and 25%. In relation to TVP inclusion and water addition, the meat content varied between 25-100%. Sample with 100% meat was used as control sample (0-sample) and burgers with S inclusion as reference samples. Samples were analyzed for cooking loss, shear force and texture profile (hardness, fracturability, springi-ness, cohesiveness, gumminess, chewiness and resilience) which was measured with a compression method. Based on the results of the instrumental analysis, five different burger samples were selected and evaluated for sensorial properties (chewiness, biting force, juiciness and pasty mouthfeel). The highest TVP moisture content was in OF and lowest in FO, hence the difference between S and FO was not significant. The highest water absorption was in S and lowest in OF. 25% TVP inclusion in burgers reduced the cooking loss (p<0.05) and 50% inclusion reduced it even more (p<0.05). With 25% TVP inclusion S had higher (p<0.05) cooking loss compared to FO and OF. With 50% TVP inclusion the difference was eliminated. Water addition increased cooking loss significantly (p<0.05) with each type of TVP. The FO and OF inclusion showed to weaken (p<0.05) the textural properties of burgers and reduced (p<0.05) the shear force. The reference sample S was found to maintain the structure similar as from the meat control sample. Water addition, while replacing meat, weakened also the textural properties and shear force in each TVP included sample. Based on the results, the inclusion of FO and OF in burgers reduces the cooking loss compared to the 0-sample and the reference sample S. The texture of burgers became weaker with FO and OF inclusion, however sensory evaluation revealed them to be similar to S included sample. Therefore additional studies focusing on improving the textural properties of these TVPs are needed. Faba bean and oat concentrates with higher protein contents could be needed to obtain a texture closer to meat.
  • Aalto, Kaisa (2019)
    Kauran käyttö leivonnassa on kasvattanut suosiotaan viime vuosien aikana. Gluteenittomuuden takia 100 % kauraleivonta on kuitenkin haasteellista, sillä taikinan käsiteltävyys vaikeutuu sitkon puuttuessa. Oikeanlaisen taikinan konsistenssin saavuttamiseksi ja onnistuneen leivonnan kannalta on tärkeää tunnistaa kauran vedensidontakykyyn vaikuttavat tekijät. Tutkimuksessa tarkasteltiin eri kauralajikkeiden beetaglukaanipitoisuuden yhteyttä vedensidontaan. Tavoitteena oli myös vertailla eri kauralajikkeista tehtyjen taikinoiden konsistenssia ja valmiiden leipien rakenteellisia ja aistinvaraisia ominaisuuksia. Kokeellisessa osiossa tutkittiin viidestä eri kauralajikkeesta valmistettujen jauhojen ja hiutaleiden vedensidontaa ja siihen vaikuttavia tekijöitä. Taikinan konsistenssimittauksia ja leivontakokeita varten näytteistä valmistettiin kaksi erilaista taikinaa, joissa toisessa käytettiin pelkästään kaurajauhoja ja toisessa puolet kaurajauhoista korvattiin saman lajikkeen kaurahiutaleilla. Leivonnan onnistumiseksi taikinoissa käytettiin apuna psylliumia. Kaurajauhoista sekä kaurajauhoista ja -hiutaleista valmistettujen taikinoiden konsistenssia tutkittiin aineenkoestuslaitteella (Texture Analyzer) käänteisen ekstruusion avulla. Leivontakokeissa leivottiin palaleipiä, joiden rakenteellisten ominaisuuksien muutoksia seurattiin myös aineenkoestuslaitteen avulla (Texture Profile Analysis). Tulosten perusteella lajikkeen vaikutus kauran vedensidontakykyyn, konsistenssiin ja leivontatuloksiin oli suuri. Beetaglukaanipitoisuuden yhteys kaurajauhojen vedensidontakykyyn ei ollut selkeä, mutta kaurahiutaleiden vedensidonta suureni beetaglukaanipitoisuuden suuretessa. Kauralajikenäytteiden konsistenssi riippui monesta eri tekijästä. Suuri beetaglukaani- ja proteiinipitoisuus näkyi suurena taikinoiden konsistenssina. Kaurahiutaleita sisältävien taikinoiden konsistenssi oli suurempi kuin vain kaurajauhoja sisältävien taikinoiden. Suuri taikinan konsistenssi helpotti taikinan käsittelyä ja muokkaamista. Konsistenssin suuruudella ei ollut suoraa yhteyttä valmiiden leipien rakenteellisiin ominaisuuksiin. Muutokset leipien rakenteessa tapahtuivat kypsymisen aikana ja johtuivat todennäköisesti lajikkeiden erilaisista liisteröitymislämpötiloista ja tärkkelyksen käyttäytymisestä paiston aikana. Liisteröityneen kauran lisääminen taikinan joukkoon paransi leipien rakenteellisia ominaisuuksia ja säilymistä.
  • Mykrä, Emmi (2013)
    Oat (Avena sativa L.) is a crop grown for feed and for food industry. It is the most used fodder plant after barley in Finland and is also exported. In 2011, oat was grown on 308 200 hectares in Finland and the average yield per hectare was 3390 kg. Several fungal and virus diseases cause remarkable crop losses in oats. Especially in the temperate zone, the most common disease is the head blight caused by Fusarium species. These fungi overwinter as mycelium or spores and produce mycotoxins. In Finland, F. culmorum is a common DON toxin producer and F. langsethiae is a T-2/HT-2 toxin producer in oats. Toxins affect the quality of oat yield and can make it unsuitable for use. Therefore, the amounts of mycotoxin allowed in cereals are stipulated by food safety authorities. This thesis was a part of MTT Agrifood Research Finland’s Hyötygeeni project. The aim of the research was to study resistance of eight oat cultivars to F. culmorum and F. langsethiae. Indicators of resistance were germination of the infested seeds, the proportion of infected seeds and the amounts of mycotoxins. The trials were made in greenhouse with artificial inoculations. The results indicated that four cultivars expressed similar levels of resistance to both Fusarium species. Three cultivars had better resistance to F. langsethiae than F. culmorum and only one cultivar had better resistance to F. culmorum than F. langsethiae. In future research, the results can be utilized in resistance breeding. Global warming will increase the risk of plant diseases. On that account importance of breeding will be emphasized.
  • Poudel, Hari (2021)
    Meat bone meal contains considerable amount of nutrients (on average 8% N, 5% P, 1% K and 10 % Ca). Therefore, it can be used as fertilizer for different crops. Whether meat bone meal (LL) can achieve similar effect in increasing the grain yield and grain quality of oat as meat bone meal mixed with biotite (LB), meat bone meal mixed with blast furnace slag (LB) and meat bone meal mixed with lime (LK) or not were analyzed in this study. Two field experiments: one in Viikki experimental farm, and other in suitia experimental farm of the University of Helsinki were carried out in the summer of 2005. LL, LB, LM, and LK were applied in three N levels: 60, 90 and 120 kg N ha-1 in Viikki and Suitia experimental farms. In both experimental farm, oat grain yield, oat grain test weight, and oat 1000-grain weight did not differ between the fertilizer types. In Suitia experimental farm, oat grain yield and 1000-grain weight increased with increasing the N-levels but not oat test weight whereas in Vikki experimental farm, oat grain yield, oat test weight, and oat 1000-grain weight did not increase with increasing the N levels. Since the N/P ratio of meat bone meal is considerably narrower than the normal nutrient uptake ratio of cereals, hence, if it is applied to meet the N demand of crops then P in soil would be surplus. Therefore, due to the P residual effect, it is recommended not to use meat bone meal in the following year or even for the whole crop rotation but recommended to grow green manure crops as for nitrogen resources to organic farms after using meat bone meal. Since K content of meat bone meal is rather low therefore, to balance the nutrient contents in meat bone meal, some of the most viable alternatives for additional K such as biotite, vinasse, potassium sulphate could be added to meat bone meal to achieve meat bone meal-NPK contents more optimal for crops.
  • Sneck, Anna-Maria (2020)
    The aims of the thesis included firstly to develop a process to prepare an oat-based milk substitute (OBMS) model in laboratory conditions representing industrial scale processing. After that, the quality of the oat-based milk substitutes prepared using the developed model was assessed and related with differences in the compositions of oats. The hypothesis was that the oat samples differ in terms of their behaviour during milk substitute manufacturing as well as final quality characteristics of the milk substitute. The OBMS process included mixing of oat flour with water, homogenisation and enzymatic hydrolysis of starch with α-amylase followed by enzyme inactivation, salt addition, pH-adjustment and removal of insoluble particles. Calcium phosphate and oil were added to the liquid milk phase after which a second homogenisation step and a final heat treatment were performed. The final OBMS was characterised in terms of mass yield, protein and dry matter contents, reducing sugars, particle size, viscosity, colloidal stability and colour. A functional OBMS process was developed and predictably, the oat samples behaved differently in the OBMS process. Mass yield of the OBMS increased as the starch content of the oat groat increased. High ash content of the oat groat correlated well a high protein content in the final OBMS. Viscosity and redness of the final product predicted well the milk yield and furthermore, it was noted that the higher the viscosity of the OBMS was, the slower it sedimented. This work provides relevant information on the oat composition that is suitable for oat-based milk substitutes.
  • Kivikko, Jenni (2023)
    Oats and peas have good nutritional composition and they could make up a favourable raw material combination for extruded food products. However, there are only few studies on their suitability for dry extrusion, especially for textured vegetable protein products (TVP). Based on protein content, dry extrudates can be divided into TVP products having fibrous structure (> 30% protein) and snack products having puffed structure (< 30 % protein). Differences in the structures of extrudates are formed as a result of the raw materials and extrusion parameters. The structure is formed in the extruder chamber, where different unit operations (for example mixing, ripening and shaping) cause many physicochemical changes in the raw materials, such as gelation of starch, denaturation and rearrangement of proteins in flow direction. The aim of the study was to find out how different extrusion parameters, oat raw materials and them concentration affect the properties of TVP products. Oat-based TVP products were targeted to have fibrous structure and resistance for soaking. In the first step, four oat raw materials in three different concentrations (25 %, 30 % and 35 %) were extruded with pea protein isolate. Moisture content, expansion, bulk density, water binding capacity, hardness and chewiness were determined from the products and a soup test simulating cooking was performed. The nutritional contents were calculated based on information received from raw material manufacturers. Based on the analysis results, the best of the oat raw materials (oat protein flour) was chosen for the second stage of the experiments. In the second stage, oat protein flour concentrations of 40%, 50% and 60% of the dry matter were tested. The extrudates were subjected to the same analyses as before. The oat raw material and its concentration were found to have statistically significant effects on many product properties, such as expansion and hardness. The best oat raw material was oat protein flour, from which the extruded products formed a fibrous and soaking-resistant structure. Increasing the oat content of the pulp in the case of oat protein flour resulted in a harder product and the expansion and water binding capacity decreased. Increasing the screw rotation speed was found to increase as well as expansion and water binding capacity. Based on the analyses and sensory observations, it was not possible to decide on the best extrudate, because the evaluation was most influenced by the evaluator's preference questions about for example meat structure. Based on this research, by combining oats and peas it is possible to obtain well-structured TVP products with a concentration of up to 60 % oat protein flour. It may be possible to increase the oat content of the extrudates by combining many oats raw materials, but at the same time it is necessary to ensure that the other properties of the extrudates are preserved.
  • Ketonen, Krista (2014)
    Variation of the protein and amino acid content of barley, wheat and oats were studied. Diets based on grain samples of different protein content were optimized for pigs and poultry.The study went on to optimize diets for pigs and poultry with grains of different protein contents. The amino acid and raw protein analysis was undertaken on 38 grain samples. Correlations were calculated between different variables in grain samples and linear regression analysis was conducted between the protein and amino acid composition. The best estimate for amino acid concentrations of cereals was the protein content. The relative content of amino acids decreases as protein content increases and especially so in barley and wheat. Most reliable regression equations between amino acid and protein content were made for barley and wheat samples. For oat reliable regression equations could not be made. Oats also differed by other features from barley and wheat as it correlated with different variables compared to barley and wheat. Amount of needed protein concentrate levels decreased when barley and wheat protein and amino acid contents were considered in optimization. Protein concentrate levels did not decrease when used oat sample with highest protein content.
  • Laine, Juhana (2011)
    The literature review focused on the composition of oats along with wheat-free oat baking technology. Enzyme active baking and rye malt utilization in low gluten baking was also reviewed. In the experimental part the effect of an extract prepared from rye malt sourdough on dough viscosity and oat bread quality was studied in order to develop technology to good quality rye flavored oat bread. Rye malt flour of high enzyme activity was used to prepare a sourdough enabling degradation of rye prolamins, harmful to celiac patients. Rye malt extract was prepared from the sourdough by centrifugation. Part of the extract was heated for enzyme inactivation to compare the effects of the enzyme active and inactive extracts on oat dough and bread. The extract was used for baking 15, 25 and 30 % (dough weight) by reducing water. Miniature size breads (20 g) were baked in small pans. Dough viscosity was measured to show partial hydrolyzation of beta-glucan due to enzyme activity. Rye flavor was measured with the help of trained jury. Rye malt extract decreased dough pH approximately from 5.8 to 4.4 and increased the titratable acidity. The dough was less viscous when using enzyme active extract and more viscous when using the inactivated extract. The rye malt extract increased bread firmness and flavor and aroma were improved. Also the pores in the crumb were smaller and more evenly distributed. The inactivated extract increased bread crumbliness. The results suggest that the production of good quality rye flavored oat bread is technologically possible when using an enzyme active extract. This can possibly be explained by the low pH inhibiting the amylases together with high gelatinization temperature of oat starch. During fermentation, the pH of the rye malt sourdough drops so low that it inhibits the excessive ?-amylase activity in the dough so that excessive starch hydrolysation cannot occur. Therefore the use of the rye malt extract in baking process is possible without inactivation. Sourdough fermentation as part of gluten-free baking can improve bread color, aroma, flavor and texture. Also, the addition of rye malt extract improved mold-free time by lowering the pH. It seems that with the help of this technology it is possible to add long yearned rye flavor to low gluten oat bread. Based on earlier results it was concluded that it is possible to achieve bread prolamin content of 63.5 mg/kg. However, it should be possible to obtain even better results with the help of further development.
  • Grönroos, Sanna (2021)
    Organic agriculture is growing steadily in Europe. Demand for organic products and pressure from policy changes in the EU have created a need for organic seed material. One of the limiting factors is the lack of organic variety testing. Currently no official organic Value of Cultivation and Use (VCU) trials or standards for organic variety testing excist in the EU. Plant breeding companies like Boreal Plant Breeding want to offer varieties for organic farmers but they lack information on the performance of their varieties in organic conditions. The main objective of this experiment was to determine the most important variety traits in organic agriculture in Finland and which of the Boreal Plant Breeding oat varieties exhibit the most favourable traits for organic growing conditions. Relationships between observed traits were also examined. A wide range of observations and measurements were performed from the trial throughout the growing season. Quality analysis of the yield were performed after harvest. The objects of examination during growing season included growth development, leaf area index (LAI), nutrient status with SPAD (Soil and Plant Analysis Development) measurements, plant height and yield components. Plant height and LAI appeared to be the best indicators for evaluation of performance potential of oat in organic conditions. SPAD value wasn’t found to have a connection to oat yield nor was it an indicator for oat LAI. High LAI increased oat height, yield and yield component shoots/m2 but effected negatively on the yield component panicles/m2 during the end of stem elongation. Plant height was a good indicator of yield level. The number of weeds and LAI value didn’t have a connection in this experiment and neither did weed number and yield. The early and late varieties varied in their reaction to the low-input growing conditions. Early varieties had generally lower yield but better yield quality than the late varieties. ‘Nella’ showed potential to be a variety with good yield quality and high yield in low-input conditions in Southern Finland. Area of cultivation and the end use of the oat are important factors in variety selection.