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This study investigated the bioaccessibility of folate in wheat bread baked with different ingredients and processing methods. Next, different matrices were spiked with 5-methyltetrahydrofolate, gallic acid (GA), or both to investigate the stability of 5-methyltetrahydrofolate during in vitro digestion. The folate bioaccessibility in bread varied from 44 to 96%. The inclusion of whole-grain or faba bean flour significantly improved both folate content and bioaccessibility. Baking with yeast increased the folate content by 145% in bread but decreased folate bioaccessibility compared to the bread without added yeast because of the instability of 5-methyltetrahydrofolate. Spiking experiments confirmed oxidation as a critical reason for 5-methyltetrahydrofolate loss during digestion. However, GA protected this vitamer from degradation. Additionally, 5-methyltetrahydrofolate was less stable in whole-grain wheat matrices than other matrices. This study demonstrated that the stability of 5-methyltetrahydrofolate is crucial for folate bioaccessibility in bread, and methods for stabilizing this vitamer should be further studied.

Demand for plant-based meat alternatives has increased in recent years due to concerns about health, ethics, the environment, and animal welfare. Nevertheless, the market share of plant-based meat alternatives must increase significantly if they are to support sustainable food production and consumption. Flavor is an important limiting factor of the acceptability and marketability of plant-based meat alternatives. Undesirable chemosensory perceptions, such as a beany flavor, bitter taste, and astringency, are often associated with plant proteins and products that use them. This study reviewed 276 articles to answer the following five research questions: (1) What are the volatile and nonvolatile compounds responsible for off-flavors? (2) What are the mechanisms by which these flavor compounds are generated? (3) What is the influence of thermal extrusion cooking (the primary structuring technique to transform plant proteins into fibrous products that resemble meat in texture) on the flavor characteristics of plant proteins? (4) What techniques are used in measuring the flavor properties of plant-based proteins and products? (5) What strategies can be used to reduce off-flavors and improve the sensory appeal of plant-based meat alternatives? This article comprehensively discusses, for the first time, the flavor issues of plant-based meat alternatives and the technologies available to improve flavor and, ultimately, acceptability.

Both the liberation and stability of endogenous folate are relevant to the bioaccessibility of folate. Since folates are unstable, in addition to studying the natural folate content in foods, bioaccessibility should be considered. To understand folate changes during digestion, a mixture of standard folate compounds was subjected to a static in vitro gastrointestinal digestion assay. Next, different types of bread were analysed to study how food matrices influence folate bioaccessibility. Folates were identified and quantitated by a UHPLC-PDA/FL method. Folic acid and 10-formylfolic acid were stable throughout the digestion, and the conversions among formyl folates and 5,10-methenyltetrahydrofolate were triggered at the gastric phase. Tetrahydrofolate began to degrade during the oral phase and was lost completely during the gastric phase. During the intestinal phase, 5-methyltetrahydrofolate began to degrade and suffered a 60% loss. With bread matrices, folate conversions and the decrease of reduced folates were also common, but the extent of changes varied. Generally, rye breads had the highest (80–120%) bioaccessibility of folate, while oat breads had the lowest (31–102%). The high proportion of 5-methyltetrahydrofolate could result in low bioaccessibility because of its relatively low stability during digestion in bread matrices. An increase in 10-formylfolic acid content was observed for all the breads, but 10-formyldihydrofolate seemed to be more stable in rye breads than in oat and wheat breads. The results showed that folates undergo significant changes during digestion and that food matrices could be modified to affect these changes towards better folate bioaccessibility.

Demand for plant-based meat alternatives has increased in recent years due to concerns about health, ethics, the environment, and animal welfare. Nevertheless, the market share of plant-based meat alternatives must increase significantly if they are to support sustainable food production and consumption. Flavor is an important limiting factor of the acceptability and marketability of plant-based meat alternatives. Undesirable chemosensory perceptions, such as a beany flavor, bitter taste, and astringency, are often associated with plant proteins and products that use them. This study reviewed 276 articles to answer the following five research questions: (1) What are the volatile and nonvolatile compounds responsible for off-flavors? (2) What are the mechanisms by which these flavor compounds are generated? (3) What is the influence of thermal extrusion cooking (the primary structuring technique to transform plant proteins into fibrous products that resemble meat in texture) on the flavor characteristics of plant proteins? (4) What techniques are used in measuring the flavor properties of plant-based proteins and products? (5) What strategies can be used to reduce off-flavors and improve the sensory appeal of plant-based meat alternatives? This article comprehensively discusses, for the first time, the flavor issues of plant-based meat alternatives and the technologies available to improve flavor and, ultimately, acceptability.

A common assumption exists according to which machine learning models improve their performance when they have more data to learn from. In this study, the authors wished to clarify the dilemma by performing an empirical experiment utilizing novel vocational student data. The experiment compared different machine learning algorithms while varying the number of data and feature combinations available for training and testing the models. The experiment revealed that the increase of data records or their sample frequency does not immediately lead to significant increases in the model accuracies or performance, however the variance of accuracies does diminish in the case of ensemble models. Similar phenomenon was witnessed while increasing the number of input features for the models. The study refutes the starting assumption and continues to state that in this case the significance in data lies in the quality of the data instead of the quantity of the data., Presented in International Workshop on Data Quality for Intelligent Systems (DQIS), which was a co-located event of QRS 2021 (The 21st IEEE International Conference on Software Quality, Reliability, and Security)

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe.

Due to COVID-19, companies were forced to adopt new work processes, and reduce modern work environments such as collaboration spaces. Professionals from many fields were forced to work remotely, almost overnight. Little is known about the impact of such non-volunteer remote work on productivity, stress, and other key aspects of work performance. To further our understanding of the impacts of this situation and remote work in general, we conducted an exploratory study by studying 28 knowledge work professionals (researchers, software developers, interior designers, service designers, and development consultants) from the viewpoint of perceived productivity and aspects affecting it in this unusual setting. Early results showed the positive influence of self-efficacy and teamwork on productivity during remote work, while no moderating effect of measured physical stress on productivity either through the intrinsic or social factor was present. peerReviewed

Machine Learning (ML) has been taking significant evolutionary steps and provided sophisticated means in developing novel and smart, up-to-date applications. However, the development has also brought new types of hazards into the daylight that can have even destructive consequences required to be addressed. Evasion attacks are among the most utilized attacks that can be generated in adversarial settings during the system operation. In assumption, ML environment is benign, but in reality, perpetrators may exploit vulnerabilities to conduct these gradient-free or gradient-based malicious adversarial inference attacks towards cyber-physical systems (CPS), such as smart buildings. Evasion attacks provide a utility for perpetrators to modify, for example, a testing dataset of a victim ML-model. In this article, we conduct a literature review concerning evasion attacks and countermeasures and discuss how these attacks can be utilized in order to deceive the, i.e., CPS smart lock system’s ML-classifier to gain access to the smart building. peerReviewed

Cereals and legumes are rich in folate. However, due to the instability of folate, processing and digestion can induce significant folate loss. In this paper, folate bioaccessibility of faba bean, oat, rye and wheat flours and pastes was studied using a static in vitro digestion model. Folate bioaccessibility depended on food matrices, varying from 42% to 67% in flours and from 40% to 123% in pastes. Digestion was associated with the inter conversion of formyl folates, as well as the increase of oxidised vitamers and decrease of reduced vitamers. Especially in faba bean, 5-methyltetrahydrofolate showed surprisingly good stability both in digestion and heat treatment, resulting in high bioaccessibility. The physiological concentration of ascorbic acid did not stabilise folate in digestion; however, a higher level helped to maintain reduced vitamers. Heat treatment (10-min paste making) could improve folate bioaccessibility by liberating folate from the food matrices and by altering folate vitamer distribution.

Cereal-based fermented foods (CBFF) are frequently consumed by young children in West-Africa. Seven CBFF types (gelatinized doughs, porridges, dumplings, and fritters, made from corn, sorghum or pearl millet) were produced according to the commonly used methods in traditional production units in Burkina Faso. Their total folate content, analyzed using a microbiological method, was between 1.8 and 31.3 mu g/100 g fresh weight. Folate degradation occurred at several steps during the cereal grain processing into CBFF, for instance during debranning (-51%), soaking (-20% to -49%) and wet-milling (-39% to -59%). Conversely, fermentation increased the folate content of some CBFF (+ 9 to + 27%). Folate bioaccessibility, assessed using a static in vitro digestion model, ranged from 23% to 81%. The bioaccessible folate content was influenced by the total folate content, the food matrix structure, and folate stability. CBFF contribution to the reference folate intake for young children was at most 23%. This work generated new information on the influence of traditional processing on the vitamin B9 content of CBFF, and the first data on folate bioaccessibility in West African CBFF.

Deficiency of correctly implemented and robust defence leaves Internet of Things devices vulnerable to cyber threats, such as adversarial attacks. A perpetrator can utilize adversarial examples when attacking Machine Learning models used in a cloud data platform service. Adversarial examples are malicious inputs to ML-models that provide erroneous model outputs while appearing to be unmodified. This kind of attack can fool the classifier and can prevent ML-models from generalizing well and from learning high-level representation; instead, the ML-model learns superficial dataset regularity. This study focuses on investigating, detecting, and preventing adversarial attacks towards a cloud data platform in the cyber-physical context. peerReviewed

IoT sensors and sensor networks are widely employed in businesses. The common problem is a remarkable number of IoT device transactions are unencrypted. Lack of correctly implemented and robust defense leaves the organization's IoT devices vulnerable to numerous cyber threats, such as adversarial and man-in-the-middle attacks or malware infections. A perpetrator can utilize adversarial examples when attacking machine learning (ML) models, such as convolutional neural networks (CNN) or deep neural networks (DNN) used, e.g., in DaaS cloud data platform service of smart buildings. DaaS cloud data platform's function in this study is to connect data from multiple IoT sensors, databases, private on-premises cloud services, public or hybrid cloud services into a metadata database. This study focuses on reviewing adversarial attack threats towards artificial intelligence systems in the smart building's context where the DaaS cloud data platform services under various information propagation chain structures utilizing ML models and reviews. Adversarial examples can be malicious inputs to ML models providing erroneous model outputs while appearing to be unmodified in human eyes. This kind of attack can knock out the classifier, prevent ML model from generalizing well, and from learning high-level representation, but instead to learn superficial dataset regularity. The purpose of this study is to investigate, detect, and prevent cyber-attack vectors, such as adversarial attacks towards DaaS cloud data platform. peerReviewed

Gathering and utilizing stored data is gaining popularity and has become a crucial component of smart building infrastructure. The data collected can be stored, for example, into private, public, or hybrid cloud service infrastructure or distributed service by utilizing data platforms. The stored data can be used when implementing services, such as building automation (BAS). Cloud services, IoT sensors, and data platforms can face several kinds of cybersecurity attack vectors such as adversarial, AI-based, DoS/DDoS, insider attacks. If a perpetrator can penetrate the defenses of a data platform, she can cause significant harm to the system. For example, the perpetrator can disrupt a building’s automatic heating system or break the heating equipment by using a suitable attack vector for a data platform. This chapter focuses on examining possibilities to protect cloud storage or data platforms from incoming cyberattacks by using, for instance, artificial-intelligence-based tools or trained neural networks that can detect and prevent typical attack vectors. peerReviewed

Aims Lactococcus lactis N8 and Saccharomyces boulardii SAA655 were investigated for their ability to synthesize B-vitamins (riboflavin and folate) and their functional role as microbial starters in idli fermentation. Methods and Results In this study, ultra-high performance liquid chromatography and microbiological assay were used to determine the total riboflavin and folate content respectively. Increased levels of folate were evident in both L. lactis N8 and S. boulardii SAA655 cultivated medium. Enhanced riboflavin levels were found only in S. boulardii SAA655 grown medium, whereas decreased riboflavin level was found in L. lactis N8 cultivated medium. To evaluate the functional role of microbial starter strains, L. lactis N8 and S. boulardii SAA655 were incorporated individually and in combination into idli batter, composed of wet grounded rice and black gram. For the experiments, naturally fermented idli batter was considered as control. The results indicated that natural idli fermentation did not enhance the riboflavin level and depleted folate levels by half. In comparison with control, L. lactis N8 and S. boulardii SAA655 incorporated idli batter (individually and in combination) increased riboflavin and folate levels by 40–90%. Apart from compensating the folate loss caused by natural fermentation, S. boulardii SAA655 fermented idli batter individually and in combination with L. lactis N8 also showed the highest leavening character. Moreover, the microbial starter incorporation did not significantly influence the pH of idli batter. Conclusion Incorporation of L. lactis N8 and S. boulardii SAA655 can evidently enhance the functional and technological characteristics of idli batter. Significance and Impact of the Study UN General Assembly declared 2016 the International Year of pulses emphasizing the importance of legumes as staple food. Furthermore, this is the first experimental report of in situ biofortifcation of riboflavin and folate using microbes in pulse based fermented staple food. The current study suggests possible avenues for research towards an economical strategy to reduce B-vitamin deficiency among the consuming population.

Year-round greenhouse production in northern latitudes depends on the use of artificial lighting. Light emitting diodes provide a promising means to save energy during cultivation as well as to modify the light spectrum to regulate the growth and quality of the crop. We compared the effects of light emitting diode lighting with different spectral compositions on the growth, development and nutritional quality of lettuce ( Lactuca sativa L. ‘Frillice’). We show that warm-white and warm-white supplemented with blue spectra provide equal growth and product quality compared to conventional high-pressure sodium lighting in the absence and presence of daylight. Our data indicate that for biomass accumulation, the far-red component in the light spectrum is more critical than green light or the red/blue ratio. Furthermore, we demonstrate that a red + blue spectrum increases the concentration of several vitamins in lettuce. However, biomass accumulation using this spectrum was insufficient when daylight was excluded.

Injera is an Ethiopian fermented flatbread preferably made from whole grain cereal (tef). Tef it is increasingly used to produce gluten-free pasta and bread, but the folate content of teff and products made from it remains unknown. Given that folate deficiencies lead to several health disorders, the aim of this study was to quantify folate in each of the three main steps of traditional processing of tef injera. Total folate contents of tef flour, fermented batter and injera were determined through microbiological assays using Lactobacillus rhamnosus (ATCC 7469). Folate content of tef flour was 8.7 mu g/100 g of dry matter content, which is in the same range as the richest cereals like oats. The increase in folate content due to fermentation was highly variable (60-148%). Cooking always led to folate losses, with a maximum of 52.8%. Altogether, injera processing increased folate retention between 38.0 and 121.8%. Folate content of injera was 14.3 mu g/100 g on fresh weight-basis. Tef injera can contribute up to 10% of the recommended nutrient intake of folate for children aged 1-3 and women of reproductive age. Although the folate content of teff is already high, future studies should focus on optimizing the folate content of injera.

Tämän raportin tarkoituksena on tarkastella tekoälyn hyödyntämistä rakennusten ennakoivassa kunnossapidossa. Raportissa esitellään KIRA-digi –hanke ja kuvataan Jyväskylän yliopiston KIRA-digi –pilottihanke. Raportin alussa on tekoälyn kehityspolku ja menetelmiä koskeva luku, jossa määritellään tekoälyn käsite ja tekoälyn menetelmiä, kuten neuroverkot, kone- ja syväoppiminen. Kolmas luku koskee älykkäitä rakennuksia ja kaupunkeja sekä esineiden internetiä (IoT), sensoreita, analytiikkaa, päälle puettavia laitteita ja teollista esineiden internetiä (IIoT). neljännessä raportin luvussa tarkastellaan rakennuksien ennakoivan kunnossapidon hyötyjä ja haittoja, kustannuksia ja säästöjä, prosessia ja annetaan esimerkkejä ennakoivan kunnossapidon ratkaisuista. Viides luku on analyysiluku, jossa esitellään ja analysoidaan Lehto Asunnot Oy:n asunnoista kerättyä IoT-sensoridataa. Lisäksi luvussa on osana tekoäly- ja teknologiakartoitus, jossa käsitellään pilvipalveluteknologiaa, sen hinnoittelua ja tekoälyä hyödyntäviä ratkaisuehdotuksia Lehto Asunnot Oy:n tarpeisiin.

The in situ production of active vitamin B12 was investigated in aqueous cereal-based matrices with three strains of food-grade Propionibacterium freudenreichii. Matrices prepared from malted barley flour (33% w/v; BM), barley flour (6%; BF), and wheat aleurone (15%; AM) were fermented. The effect of cobalt and the lower ligand 5,6-dimethylbenzimidazole (DMBI) or its natural precursors (riboflavin and nicotinamide) on active B12 production was evaluated. Active B12 production was confirmed by UHPLC-UV-MS analysis. A B12 content of 12-37 mu g.kg(-1) was produced in BM; this content increased 10-fold with cobalt and reached 940-1,480 mu g.kg(-1) with both cobalt and DMBI. With riboflavin and nicotinamide, B12 production in cobalt-supplemented BM increased to 712 mu g.kg(-1). Approximately, 10 mu g.kg(-1) was achieved in BF and AM and was increased to 80 mu g.kg(-1) in BF and 260 mu g.kg(-1) in AM with cobalt and DMBI. The UHPLC and microbiological assay (MBA) results agreed when both cobalt and DMBI or riboflavin and nicotinamide were supplemented. However, MBA gave ca. 20%-40% higher results in BM and AM supplemented with cobalt, indicating the presence of human inactive analogues, such as pseudovitamin B12. This study demonstrates that cereal products can be naturally fortified with active B12 to a nutritionally relevant level by fermenting with P. freudenreichii.

Aims The focus of the research was to identify yeasts from barley kernels in order to study their folate production capability while maintaining high viscosity caused by soluble fibres in oat bran fermentation. Methods and Results The 65 isolated yeasts were characterized by API carbohydrate utilization tests, and assays for extracellular enzyme activities were the following: amylase, beta-glucanase, cellulase or CMCase, lipase, protease and xylanase. Yeasts were identified by partial DNA sequencing of the 25S D1/D2 and ITS1-5.8S-ITS2 regions. They belonged to the genera Aureobasidium, Cryptococcus, Pseudozyma and Rhodotorula. Folate production was determined from supernatant and cells grown in a rich laboratory medium or directly from oat bran solution inoculated with the appropriate yeast. Food yeasts, Saccharomyces cerevisiae, Candida milleri, Kluyveromyces marxianus and Galactomyces geotrichum, were used for comparison. Most of the yeasts isolated from barley destroyed the solid, viscous structure of the oat bran solution, indicating that they degraded the viscosity-generating soluble fibres, considered to be nutritionally advantageous. The best folate producers were S. cerevisiae, followed by Pseudozyma sp., Rhodotorula glutinis and K. marxianus. The yeasts maintaining high viscosity were used together with lactic acid bacteria (LAB) Streptococcus thermophilus or Lactobacillus rhamnosus to ferment oat bran solution. None of the yeasts isolated from barley, contrary to S. cerevisiae and C. milleri, produced together with LAB significant amounts of folate. Conclusions Fermentative yeasts together with LAB are potential for use in developing novel high folate content healthy foods and snacks from oat bran. Significance and Impact of the Study High soluble fibre content and high natural folate content but low energy content food and snack products with pleasant fermentation aroma provide possibilities for new developments in the food industry.

This study aimed to investigate the riboflavin, niacin, folate and B12 content in microalgae powders. Riboflavin was determined with an ultra-high-performance liquid chromatographic (UHPLC) method after extraction and a two-enzyme treatment. Niacin analysis involved mild acidic hydrolysis, with niacin quantitated as the sum of nicotinic acid and nicotinamide using a UHPLC method. Both a microbiological (MBA) and a UHPLC method was used for vitamin B12 quantification as a cyanocobalamin (CNCb1) and UHPLC-mass spectrometry was used to confirm the vitamin B12 form. Total folate was determined both with MBA and as a sum of the vitamers with a UHPLC method after extraction and tri-enzyme treatment. The riboflavin and niacin content varied from 21 to 41 mu g/g and 0.13-0.28 mg/g, respectively, in Chlorella sp., Spirulina (Arthrospira sp.) and Nannochloropsis gaditana powders. Chlorella powders were, on average, richer in total folate (19.7 mu g/g) than Spirulina powders were (3.5 mu g/g). The sum of the folate vitamers determined with UHPLC matched better with the microbiological total folate content in Chlorella than in Spirulina powders. Pseudovitamin B12 was the predominant form over active vitamin B12 in Spirulina powders, whereas Chlorella sp. and N. gaditana powders solely contained active vitamin B12 up to 2.1 mu g/g.

Propionibacterium freudenreichii is the only generally recognized safe (GRAS) bacterium known to synthesize active vitamin B12 and offers previously untapped potential for naturally fortifying foods with vitamin B12. Biosynthesis of the lower ligand 5,6-dimethylbenizimidazole (DMBI) is often a key limiting factor in the production of active vitamin B12 in Propionibacteria. Here, we studied the effect of the natural food-grade precursors of DMBI [riboflavin (RF) and nicotinamide (NAM)] on vitamin B12 production by 27 P. freudenreichii and 3 Propionibacterium acidipropionici strains in whey-based medium. We employed sensitive and selective UHPLC and LC–MS/MS to confirm and quantify the synthesized vitamin B12. In 12 P. freudenreichii strains, co-supplementation with RF (40 μM) and NAM (27 mM) increased the volumetric yield of vitamin B12 up to 4-fold compared to the control cultures. For the majority of these strains, the production level with RF and NAM exceeded the yield obtained with DMBI supplementation (100 μM). The significant positive correlation between RF consumption and vitamin B12 production suggests that RF is proportionally directed towards vitamin B12 biosynthesis. This study shows that the availability of RF and NAM enhances the production of active vitamin B12 by P. freudenreichii in a strain-dependent manner.

Vitamin B12 exists naturally in foods of animal origin and is synthesised only by certain bacteria. New food sources are needed to ensure vitamin B12 intake in risk groups. This study aimed to investigate the stability of added cyanocobalamin (CNCbl, chemically modified form) and hydroxocobalamin (OHCbl, natural form) and in situ-synthesised vitamin B12 in breadmaking. Samples were analysed both with a microbiological (MBA) and a liquid chromatographic (UHPLC) method to test applicability of these two methods. Proofing did not affect CNCbl and OHCbl levels. By contrast, 21% and 31% of OHCbl was lost in oven-baking steps in straight- and sponge-dough processes, respectively, whereas CNCbl remained almost stable. In sourdough baking, 23% of CNCbl and 44% of OHCbl were lost. In situ-produced vitamin B12 was almost as stable as added CNCbl and more stable than OHCbl. The UHPLC method showed its superiority to the MBA in determining the active vitamin B12.

Fifty pairs (experiment 1) of 7-week-old blue fox (Alopex lagopus) cubs (live-weight 1.9 kg) were fed incremental level of folic acid (0, 5, 10, 20 and 40 mg kg −1 dry matter (DM)), for 4 weeks in order to investigate the effect of folate status on formate metabolism in blue foxes. Incremental folic acid feeding increased hepatic folate concentrations curvlinearly (351, 1024, 1161, 1280, and 1290 g 100 g −1 ). Seven males per feeding group were injected i.p. sodium formate once, 500 mg kg −1 live-weight, after which serum formate concentrations were determined from blood samples taken at 60, 90, 120 and 180 min post-injection. Incremental dietary folic acid decreased half-life of formate (173, 130, 126, 112, and 117 min, linear effect: P< 0.05, quadratic effect: P< 0.05) and increased formate disappearance rate (2.1, 2.7, 3.2, 3.2, and 3.4 mg l −1 min −1 , linear effect: P< 0.05). The effect of dietary formate intake on formic acid metabolism was studied with eight blue foxes (live-weight 8.45 kg) (experiment 2). Foxes were given formate either at a low (10.1 g kg −1 DM) or a high dietary concentration (19.7 g kg −1 DM). Foxes on high formate diets had higher mean serum formic acid concentration than foxes on low formate diets ( P< 0.01) (0.13 mg l −1 versus 0.05 mg l −1 ). The results of these experiments give new information in order to assess recommendations for the use of ensiled feedstuffs in blue fox diets. © 2002 Elsevier Science B.V. All rights reserved.

A sensitive and selective method is needed to analyse in situ produced vitamin B12 in plant-based materials, potential new dietary sources of vitamin B12. A UHPLC/UV method was developed and validated for the determination of human active vitamin B12 in cell extracts of Propionibacterium freudenreichii subsp. shermanii and after immunoaffinity purification in extracts of cereal matrices fermented by P. freudenreichii. An Acquity HSS T3 C18 column resulted in a baseline separation, a calibration curve of excellent linearity and a low limit of detection (0.075 ng/5 μL injection). As confirmed by UHPLC–MS, the active vitamin B12 could be separated from pseudovitamin B12. The recovery of vitamin B12 from purified spiked cereal matrices was good (>90%; RSD < 5%). A nutritionally relevant amount of active vitamin B12 was produced by P. freudenreichii in cereal malt matrices (up to 1.9 μg/100 g) in 24 h at 28 °C.

Purpose To compare the content of bioaccessible folate, vitamin B12, and isoflavones in tofu and tempe, as influenced by soybean variety and food processing, particularly fermentation. Principal results Raw soybeans contained 2207–2671 μg/kg (dry matter) folate, cooked tempe 1493–4143, and cooked tofu 968–1273 μg/kg, the difference was attributed to the fermentation in tempe. Vitamin B12 was detected only in tempe (0.16–0.72 μg/kg). Isoflavone aglycones were formed during soaking of soybeans, with only minor differences between the contents in cooked tempe (average 1922–2968 μg/kg) or tofu (1667–2782 μg/kg) but strongly depending on bean variety. Conclusions Folate and vitamin B12 contents were mainly influenced by microbial activity during fermentation, whereas isoflavone aglycone content was determined by bean variety. Tofu had lower folate and vitamin B12, but equal isoflavone contents as tempe. Bioaccessibility of folate (80–100%) and isoflavone aglycones (100%) were high.

The effects of genotype and environment on the content of bioactive components in rye were determined with four varieties being grown on one site for three years and on three additional sites in the third year and a fourth variety being included in all trials except year 1. Clear differences were observed in the extent to which the contents of dietary fiber components (arabinoxylan, beta-glucan, total dietary fiber) and phytochemicals (folates, alkylresorcinols, sterols, tocols, phenolic acids) varied between varieties and between the same varieties grown in different sites (United Kingdom, France, Hungary, Poland) and years (2005-2007 in Hungary), with sterols being the most stable and phenolic acids the least. However, no single variety could be selected as having the highest overall level of bioactive components or as being more stable in comparison across environments.

Analysis of the contents of bioactive components (tocols, sterols, alkylresorcinols, folates, phenolic acids, and fiber components) in 26 wheat cultivars grown in six site × year combinations showed that the extent of variation due to variety and environment differed significantly between components. The total contents of tocols, sterols, and arabinoxylan fiber were highly heritable and hence an appropriate target for plant breeding. However, significant correlations between the contents of bioactive components and environmental factors (precipitation and temperature) during grain development also occurred, with even highly heritable components differing in amount between grain samples grown in different years on different sites.

The average daily intake of folate, one of the B vitamins, falls below recommendations among the Finnish population. Bread and cereals are the main sources of folate, rye being the most significant single source. Processing is a prerequisite for the consumption of whole grain rye; however, little is known about the effect of processing on folates. Moreover, data on the bioavailability of endogenous cereal folates are scarce. The aim of this study was to examine the variation in as well as the effect of fermentation, germination, and thermal processes on folate contents in rye. Bioavailability of endogenous rye folates was investigated in a four-week human intervention study. One of the objectives throughout the work was to optimise and evaluate analytical methods for determining folate contents in cereals. Affinity chromatographic purification followed by high-performance liquid chromatography (HPLC) was a suitable method for analysing cereal products for folate vitamers, and microbiological assay with Lactobacillus rhamnosus reliably quantified the total folate. However, HPLC gave approximately 30% lower results than the microbiological assay. The folate content of rye was high and could be further increased by targeted processing. The vitamer distribution of whole grain rye was characterised by a large proportion of formylated vitamers followed by 5-methyltetrahydrofolate. In sourdough fermentation of rye, the studied yeasts synthesized and lactic acid bacteria mainly depleted folate. Two endogenous bacteria isolated from rye flour were found to produce folate during fermentation. Inclusion of baker s yeast in sourdough fermentation raised the folate level so that the bread could contain more folate than the flour it was made of. Germination markedly increased the folate content of rye, with particularly high folate concentrations in hypocotylar roots. Thermal treatments caused significant folate losses but the preceding germination compensated well for the losses. In the bioavailability study, moderate amounts of endogenous folates in the form of different rye products and orange juice incorporated in the diet improved the folate status among healthy adults. Endogenous folates from rye and orange juice showed similar bioavailability to folic acid from fortified white bread. In brief, it was shown that the folate content of rye can be enhanced manifold by optimising and combining food processing techniques. This offers some practical means to increase the daily intake of folate in a bioavailable form. B-vitamiinien ryhmään kuuluvat folaatit esiintyvät useina muotoina, vitameereina. Folaatteja tarvitaan yhden hiiliyksikön siirtoreaktioissa mm. DNA:n ja RNA:n synteesissä sekä aminohappoaineenvaihdunnassa. Folaattien puutoksen tiedetään aiheuttavan megaloblastista anemiaa ja sikiöillä hermostoputken sulkeutumishäiriöitä. Näiden vitamiinivaikutusten lisäksi folaateilla on todettu terveyttä edistäviä vaikutuksia, kuten pienentynyt riski sairastua tiettyihin syöpiin sekä sydän- ja verisuonitauteihin. Folaattianalytiikka on haastavaa, sillä folaatit esiintyvät elintarvikkeissa usein pieninä pitoisuuksina ja tuhoutuvat herkästi lämmön, valon ja hapettumisen vaikutuksesta. Suomalaisten folaattisaannista noin 40% on peräisin viljatuotteista. Lähtökohtana väitöskirjatyölle oli se, että vaikka ruis on merkittävin yksittäinen folaattilähde suomalaisessa ruokavaliossa, rukiin folaateista, niiden hyväksikäytettävyydestä ja elintarvikeprosessien vaikutuksista ei ole paljonkaan tietoa. Tutkimuksen tavoitteena oli tutkia folaattipitoisuuksien vaihtelua lajikkeiden välillä sekä keinoja lisätä pitoisuuksia elintarvikeprosesseilla. Lisäksi tutkittiin rukiin luontaisten folaattien hyväksikäytettävyyttä. Mikrobiologinen menetelmä oli luotettava ja tarkka kokonaisfolaattipitoisuuden määrittämisessä, ja suuren erotuskyvyn nestekromatografia (HPLC) soveltui hyvin vitameerien pitoisuuksien määrittämiseen. HPLC:llä määritetyt vitameerien yhteenlasketut pitoisuudet olivat kuitenkin noin 30% pienemmät kuin mikrobiologisesti määritetyt kokonaisfolaattipitoisuudet. Rukiin folaateista suurin osa oli formyloituja muotoja sekä 5-metyylitetrahydrofolaattia. Leivinhiivan käyttäminen ruisleivonnassa nosti folaattitasoa niin, että leivässä saattoi olla enemmän folaatteja kuin ruisjauhossa. Koeputkifermentaatioissa hiivojen todettiin syntetisoivan folaatteja, kun taas maitohappobakteerit pääosin kuluttivat niitä. Idätys paitsi nosti folaattipitoisuuksia, myös aiheutti selviä muutoksia vitameerijakaumaan: idätetyn rukiin tärkeimmät vitameerit olivat 5-metyylitetrahydrofolaatti sekä tetrahydrofolaatti. Juuri-iduissa folaattipitoisuudet olivat erityisen suuria. Folaattien synteesi idätyksen aikana pystyi kompensoimaan folaattien tuhoutumista idätystä seuraavissa lämpökäsittelyissä. Rukiista ja appelsiinimehusta saadut luontaiset folaatit olivat yhtä hyvin hyväksikäytettävissä kuin valkoiseen leipään lisätty foolihappo. Väitöskirjatyössä osoitettiin, että rukiin folaattipitoisuuksia pystytään merkittävästi kasvattamaan prosessoinnin keinoin ja että verrattain pienikin lisä rukiin luontaisia folaatteja vaikuttaa positiivisesti folaattistatukseen.

Manufacturing of healthy whole-grain foods demands knowledge of process-induced changes in macro-, micro- and non-nutrients. The high content of dietary fibre is a challenge in relation to good product texture and sensory quality. The stability and bioavailability of bioactive compounds have a marked influence on the health effects of cereal foods. It was confirmed that sterols, folates, tocopherols and tocotrienols, alkylresorcinols, lignans, phenolic acids and total phenolics are concentrated in the bran layers of the rye grain, and are only present at low levels in the flour endosperm. The levels of folate and easily-extractable phenolic compounds increase in germination and sourdough baking, but there are negligible changes in the levels of sterols, lignans and alk(en)ylresorcinols. The levels of tocopherols and tocotrienols are reduced during the sourdough fermentation. In conclusion, many of the bioactive compounds in whole-grain rye are stable during food processing, and their levels can even be increased with suitable processing.

P-75 Key Words: Measurement of Hypertension, Stethoscope, Electronic Stethoscope

Folate is essential for human health, playing a vital role in the metabolism of nucleic and amino acids. However, folate intake is below the recommendation in many countries. Mandatory folic acid fortification is practised in more than 80 countries around the world, but not, for example, in most EU countries. Additionally, there are concerns about excessive folic acid intake. Therefore, studying folate from natural sources, such as cereal and legume-based foods, is important. Unlike enriched folic acid, natural folates need to be liberated from the food matrix, and, further, most of them are unstable and can be lost during digestion. Thus, to understand the role of a food as a folate source, it is necessary to consider the bioaccessibility of folate, meaning the proportion of folate potentially available for absorption. However, knowledge about folate bioaccessibility in foods is still limited, especially at the vitamer level. Furthermore, the mechanisms behind how food matrices influence folate bioaccessibility are not well understood. This thesis aimed to investigate the bioaccessibility of endogenous folate in cereals and legumes. Folate bioaccessibility in cereal and legume matrices (flours, pastes and breads) was compared first. Next, the stability of folate vitamers during in vitro digestion was studied. Then, the effects of ingredients and processing methods on folate bioaccessibility were investigated. Finally, the significance of 5-methyltetrahydrofolate to folate bioaccessibility was examined. Samples were subjected to a static in vitro digestion model, and folates were analysed using ultra-high-performance liquid chromatography (UHPLC) coupled with photodiode array and fluorescence detection. Folate bioaccessibility in cereal and legume matrices ranged from 31% to 123%. Faba bean matrices generally had better folate bioaccessibility than cereal matrices. Among the breads, rye breads typically had higher folate bioaccessibility, and oat breads had lower folate bioaccessibility than the other breads. Three common trends in folate stability during in vitro digestion were found: (1) high stability of formyl pool folates, but frequent interconversion among formyl folates (10-formyldihydrofolate, 5-formyltetrahydrofolate) and 5,10-methenyltetrahydrofolate; (2) the decrease of reduced folates (tetrahydrofolate, 5-methyltetrahydrofolate, and 5-formyltetrahydrofolate); and (3) high stability of oxidised folates (folic acid and 10-formylfolic acid). These changes were universal for all studied food matrices, but the degree varied. 5-methyltetrahydrofolate was more stable in legume matrices than in cereal matrices. Both the ingredients and the processing methods affected the bioaccessibility of folate. Because of a larger formyl folate pool, whole-grain wheat bread had better folate bioaccessibility than white wheat bread. The inclusion of faba bean flour as a baking ingredient not only introduced a large formyl pool but also stabilised 5-methyltetrahydrofolate during digestion, improving both the folate content and bioaccessibility in bread. Folate bioaccessibility was easily improved with a simple paste making process. Conversely, baking with added yeast significantly enhanced the 5-methyltetrahydrofolate level in breads but decreased their folate bioaccessibility due to the instability of 5-methyltetrahydrofolate. Further experiments showed that 5-methyltetrahydrofolate was crucial for folate bioaccessibility and its stability in food matrices during the in vitro digestion was a trade-off between the pro-oxidative and protective factors. However, phenolic compounds could act as protective factors in stabilising 5-methyltetrahydrofolate. In summary, folates underwent significant changes during digestion. However, food matrices can be modified to turn these changes towards better folate bioaccessibility. Faba bean was shown to be a promising dietary source of folate. In addition to folate content, bioaccessibility should be considered when evaluating foods as folate sources. B-ryhmän vitamiineihin kuuluvaa folaattia tarvitaan mm. nukleiinihappojen synteesiin ja aminohappojen aineenvaihduntaan. Folaatin saanti jää usein alle suositusten. Sikiöiden hermostoputken sulkeutumishäiriöiden ehkäisemiseksi monessa maassa viljavalmisteita täydennetään foolihapolla. Tämä ei kuitenkaan ole yleistä EU:ssa, ja siksi on tärkeää tutkia elintarvikkeiden luontaista folaattia. Pitoisuuksien lisäksi voidaan tarkastella folaatin biosaatavuutta (bioaccessibility), jolla tarkoitetaan sitä osuutta folaatista, joka vapautuu elintarvikkeesta ja voisi imeytyä. Useimmat folaatin muodoista, vitameereista, ovat herkkiä tuhoutumaan. Folaatin biosaatavuutta ei ole juuri tutkittu etenkään vitameeritasolla, eikä elintarvikematriisin vaikutusta biosaatavuuteen ymmärretä hyvin. Väitöskirjatyön tavoite oli tutkia viljojen ja palkokasvien folaatin biosaatavuutta. Biosaatavuutta tutkittiin staattisella in vitro ruoansulatusmallilla, ja folaatit määritettiin erittäin suuren erotuskyvyn nestekromatografialla (UHPLC). Folaatin biosaatavuus vilja- ja palkokasvimateriaaleista – jauhoista, kuumennetuista jauho–vesiseoksista ja leivistä – oli 31–123 %. Vitameerien pysyvyydet ruoansulatusmallissa vaihtelivat, ja elintarvikkeissa yleisesti esiintyvä 5-metyylitetrahydrofolaatti oli pysyvämpi palkokasvi- kuin viljamateriaaleissa. Härkäpavun folaatin biosaatavuus oli parempi kuin viljojen. Ruisleipien folaatin biosaatavuus oli hyvä, kun taas kauraleivissä biosaatavuus oli heikompi. Täysjyvävehnäleivän folaatin biosaatavuus oli parempi kuin valkoisen vehnäleivän, ja härkäpapujauhon käyttäminen leivonnassa paransi sekä leivän folaattitasoa että biosaatavuutta. Biosaatavuutta pystyttiin parantamaan myös yksinkertaisella kuumennuskäsittelyllä. Leivinhiivan käyttäminen nosti kyllä leivän folaattipitoisuutta, mutta heikensi biosaatavuutta hiivan tuottaman 5 metyylitetrahydrofolaatin heikon pysyvyyden vuoksi. 5-Metyylitetrahydrofolaatin pysyvyys osoittautuikin ratkaisevan tärkeäksi folaatin biosaatavuudelle. Fenoliset yhdisteet edistivät 5-metyylitetrahydrofolaatin pysyvyyttä. Tämä väitöskirjatyö osoitti, että elintarvikematriisien muokkauksella ja valmistusaineiden valinnalla voidaan parantaa folaatin biosaatavuutta. Härkäpavun osoitettiin olevan lupaava folaatin lähde. Folaattipitoisuuden lisäksi biosaatavuus tulisi ottaa huomioon arvioitaessa elintarvikkeita folaatin lähteinä.

Vitamin B12 (later B12) intake is insufficient in developing countries, and globally, vegetarians and vegans are also at risk of B12 deficiency. Occurring naturally only in foods of animal origin, new affordable and sustainable dietary sources of B12 are needed to ensure sufficient intake. The only known food-grade producers of active B12, Propionibacterium freudenreichii strains, however, are yet to be exploited to enrich plant-based foods with B12. The B12 production capacity of P. freudenreichii depends on the strain, and the availability of the B12 lower ligand (5,6-dimethylbenzimidazole, DMBI) is a key factor for the production of active B12. Bread can be considered as a potential food for B12 fortification; yet the stability of in situ-produced B12 incorporated during breadmaking processes is not known. Current analytical methods such as the microbiological assay (MBA) lack the required specificity and the existing high-performance liquid chromatography (HPLC) methods are only capable of measuring higher B12 levels in fortified foods and supplements. The determination of active B12 in fermented foods, however, needs sensitive and selective methods. An ultra-HPLC (UHPLC) method was developed and validated to measure the active B12 contents. The identity of the B12 form was confirmed with an ion-trap or quadrupole time-of-flight mass spectrometry (MS). The B12 production capacity of 27 P. freudenreichii and 3 Propionibacterium acidipropionici strains was first studied in whey-based medium (WBM), and three of these P. freudenreichii strains were chosen to study B12 production in three aqueous cereal matrices prepared from malted barley (BM; 33% w/v), barley flour (BF; 6% w/v) and wheat aleurone (AM). Riboflavin (RF) and nicotinamide (NAM) as food-grade replacements for DMBI were investigated in WBM and cereal matrices. The stability of in situ-produced B12 and added cyanocobalamin (CNCbl) and hydroxocobalamin (OHCbl) during straight-dough, sponge-dough and sourdough breadmaking was studied. The developed UHPLC method employing an Acquity high-strength silica (HSS) T3 column showed excellent separation of active B12 from its analogues. A low limit of detection (0.075 ng/inj) enabled the measurement of the B12 levels in cell extracts directly and following immunoaffinity purification in extracts of fermented cereal matrices and B12-fortified baking samples. Analysis with UHPLC MS confirmed the production of active B12 by all 27 P. freudenreichii strains in WBM and 3 P. freudenreichii strains in cereal matrices. P. acidipropionici strains, however, produced an inactive form (pseudovitamin B12), thus making them unsuitable for active B12 fortification in foods. The level of B12 production in WBM varied considerably between the strains (0.45‒3.35 µg/mL), which increased up to 4-fold in 12 of the 27 P. freudenreichii strains following supplementation with RF and NAM. In many of these strains, the B12 yield was higher with RF and NAM co-supplementation than with DMBI. In cereal matrices without supplementation, the produced levels of active B12 (9‒37 ng/g) with P. freudenreichii strains were nutritionally significant. The B12 production increased many-fold, reaching up to 430 ng/g in BM, 39 ng/g in BF and 114 ng/g by adding cobalt (Co) and reached 712 ng/g in BM and 180 ng/g in AM with RF and NAM co-supplementation with Co. The incorporated in situ-produced B12 was retained during straight-dough breadmaking and the loss of 29% during sourdough baking was similar to the losses observed for relatively stable CNCbl. However, the added OHCbl decreased by 21%, 31% and 44% respectively in straight-dough, sponge-dough and sourdough breadmaking. These results showed that B12 produced in situ and incorporated during breadmaking was well retained in the bread prepared by the conventional breadmaking processes. This thesis shows that UHPLC combined with MS allows for the accurate identification and quantitation of low levels of active B12 in fermented food matrices (≥1 ng/g). P. freudenreichii strains could be utilised for in situ production of active B12 in cereal matrices and WBM. The availability of RF and NAM could considerably improve B12 production. The produced levels could easily fulfil the recommended dietary allowance set for B12 (e.g. 2‒2.4 µg/day for adults), and could be well retained in bread in the commonly used breadmaking processes.