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High-dimensional non-Gaussian data is widely found in the real world, such as in face recognition, facial expressions, document recognition, and text processing. Linear discriminant analysis (LDA) as dimensionality reduction performs poorly on non-Gaussian data and fails on high-dimensional data when the number of features is greater than the number of instances, commonly referred to as a small sample size (SSS) problem. We proposed a new method to reduce the number of dimensions called iterative LDA (iLDA). This method will handle the iterative use of LDA by gradually extracting features until the best separability is reached. The proposed method produces better vector projections than LDA for Gaussian and non-Gaussian data and avoids the singularity problem in high-dimensional data. Running LDA does not necessarily increase the excessive computational cost caused by calculating eigenvectors since the eigenvectors are calculated from small-dimensional matrices. The experimental results show performance improvement on 8 out of 10 small-dimensional datasets, and the best improvement occurs on the ULC dataset, from 0.753 to 0.861. For image datasets, accuracy improved in all datasets, with the Chest CT-Scan dataset showing the greatest improvement, followed by Georgia Tech from 0.6044 to 0.8384 and 0.8883 to 0.9481, respectively.

Fish protein hydrolysates (FPH) obtained by enzymatic hydrolysis allows for smart valorization of fish side streams. However, further treatments are normally needed to enhance bioactive and functional properties of the obtained FPH. At present, the commonly used methods to improve functional properties of FPH include chemical and enzymatic modification. Chemical treatments often cause environmental problems, while the enzymatic modification method requires the use of quite expensive enzymes. In recent years, emerging technologies such as ultrasound treatment (US-treatment) have shown great potential in protein modification with high efficiency and safety, low energy consumption, and low nutritional destructiveness. In this study, high-power ultrasound treatments were applied to fish protein hydrolysates (FPH) extracted from Atlantic mackerel (Scomber scombrus) side streams to improve their quality parameters. The effect of three different treatments of 300 W, 450 W and 600 W at the operating frequency of 20 kHz for 10 min on the physicochemical, structural, and functional characteristics of FPH, were examined. The results have shown that with an increase in ultrasound power, the protein solubility of FPH increased linearly, and the changes were significant for all US-treated samples compared to control (untreated) samples. US-treatment significantly increased the degree of hydrolysis of FPH samples treated with 450 W and 600 W compared to control samples. The carbonyl content of FPH increased (significantly for 450 W and 600 W), while thiol groups decreased (significantly for 300 W and 450 W). This indicated that some US-treatments induced oxidation of FPH, however the values of the protein oxidation were low. Amino acid composition of FPH revealed that US-treatment increased the proportion of essential amino acids in the sample treated with 300 W and 450 W, but the increase was not significant. After the US-treatment, all FPH samples became lighter and less yellowish and reddish, which suggest potentially higher attractiveness to consumers. In addition, the in vitro antioxidant activity was assessed using the DPPH, FRAP, and ABTS assays and the cell-free dipeptidyl peptidase IV (DPP-IV) inhibitory activity was also measured. Moreover, these biological activities were measured at cellular level utilizing human intestinal Caco-2 cells. Specifically, the FPH capacity to lower H2O2-induced reactive oxygen species (ROS) and lipid peroxidation levels was used to measure its antioxidant activity. The findings suggest that Scomber scombrus hydrolysates could find use as ingredients for promoting health.

Materials informatics often struggles with small datasets. Our study introduces the Gaussian Mixture Model Virtual Sample Generation (GMM-VSG) approach to enhance feature correlation by generating virtual samples. Applied to six small and one large dataset of 218 N-heterocyclic compounds, GMM-VSG significantly improved predictive performance. Random Forest’s R2 rose from 0.80 to 0.99, with RMSE dropping from 9.87 to 0.22. Kernel Ridge’s R2 increased from 0.70 to 0.99, and RMSE decreased from 10.08 to 0.83. KNN improved from R2 of 0.74–0.90. ANN and MLPNN also saw notable improvements. GMM-VSG is thus crucial for advancing anti-corrosion material research.

In this investigation, a quantitative structure-property relationship (QSPR) model coupled with a quantum neural network (QNN) was used to explore the corrosion inhibition efficiency (CIE) of quinoxaline compounds. Integrating quantum chemical properties (QCP) features reduced computational burden by strategically reducing the features from 11 to 4 while maintaining prediction accuracy. QNN models outperform traditional methods like artificial neural networks (ANN) and multilayer perceptron neural networks (MLPNN), with a coefficient of determination (R2) value of 0.987, coupled with diminished root mean square error (RMSE), mean absolute error (MAE), and mean absolute deviation (MAD) values of 0.97, 0.92, and 1.10, respectively. Predictions for six newly synthesized quinoxaline derivatives: quinoxaline-6-carboxylic acid (Q1), methyl quinoxaline-6-carboxylate (Q2), (2E,3E)-2,3-dihydrazono-1,2,3,4-tetrahydroquinoxaline (Q3), (2E,3E) 2,3-dihydrazono-6-methyl-1,2,3,4-tetrahydroquinoxaline (Q4), (E)-3-(4-methoxyethyl)-7-methylquinoxalin-2(1 H)-one (Q5), and 2-(4-methoxyphenyl)-7-methylthieno[3,2-b] quinoxaline (Q6), show remarkable CIE values of 95.12, 96.72, 91.02, 92.43, 89.58, and 93.63 %, respectively. This breakthrough technique simplifies testing and production procedures for new anti-corrosion materials.

Abstract Background Serine residues in the protein backbone of heavily glycosylated proteoglycans are bound to glycosaminoglycans through a tetrasaccharide linker. UXS1 encodes UDP‐glucuronate decarboxylase 1, which catalyzes synthesis of UDP‐xylose, the donor of the first building block in the linker. Defects in other enzymes involved in formation of the tetrasaccharide linker cause so‐called linkeropathies, characterized by short stature, radio‐ulnar synostosis, decreased bone density, congenital contractures, dislocations, and more. Methods Whole exome sequencing was performed in a father and son who presented with a mild skeletal dysplasia, as well as the father's unaffected parents. Wild‐type and mutant UXS1 were recombinantly expressed in Escherichia coli and purified. Enzyme activity was evaluated by LC–MS/MS. In vivo effects were studied using HeparinRed assay and metabolomics. Results The son had short long bones, normal epiphysis, and subtle metaphyseal changes especially in his legs. The likely pathogenic heterozygous variant NM_001253875.1(UXS1):c.557T>A p.(Ile186Asn) detected in the son was de novo in the father. Purified Ile186Asn‐UXS1, in contrast to the wild‐type, was not able to convert UDP‐glucuronic acid to UDP‐xylose. Plasma glycosaminoglycan levels were decreased in both son and father. Conclusion This is the first report linking UXS1 to short‐limbed short stature in humans.

Text summarization is the process of creating a text summary that contains important information from a text document. In recent years, significant progress has been made in the field of text summarization research, along with the challenges that drive research progress in the field at large. The development of textual data has sparked great interest in text summarization research, which is thoroughly reviewed in this survey study. Text summarization research improvements continue to be made to date with various approaches, such as abstractive and extractive. The abstractive approach uses an intermediate representation of the input document to produce a summary that may differ from the original text. The extractive approach means that key sentences are extracted from the source document and combined to form a summary. Despite the various methodologies and approaches recommended, the summaries produced still contain ambiguities that can be interpreted with different meanings, resulting in errors in defining ambiguities, uncertainty in measuring the quality of summaries, difficulty in modeling linguistic context, difficulty in representing semantic meanings, and difficulty in specifying types of ambiguities. This research survey offers a comprehensive exploration of text summarization research, covering challenges, classifications, approaches, preprocessing methods, features, techniques, and evaluation methods, meeting future research needs. The results provide an overview of the state of the art of recent research developments in the topic of ambiguity resolution in text summarization, such as trends in research topics and approaches or techniques used in addressing ambiguity problems in text summarization.

Congenital diaphragmatic hernia (CDH) can occur in isolation or in conjunction with other birth defects (CDH+). A molecular etiology can only be identified in a subset of CDH cases. This is due, in part, to an incomplete understanding of the genes that contribute to diaphragm development. Here, we used clinical and molecular data from 36 individuals with CDH+ who are cataloged in the DECIPHER database to identify genes that may play a role in diaphragm development and to discover new phenotypic expansions. Among this group, we identified individuals who carried putatively deleterious sequence or copy number variants affecting CREBBP, SMARCA4, UBA2, and USP9X. The role of these genes in diaphragm development was supported by their expression in the developing mouse diaphragm, their similarity to known CDH genes using data from a previously published and validated machine learning algorithm, and/or the presence of CDH in other individuals with their associated genetic disorders. Our results demonstrate how data from DECIPHER, and other public databases, can be used to identify new phenotypic expansions and suggest that CREBBP, SMARCA4, UBA2, and USP9X play a role in diaphragm development.

Purpose: The purpose of this study is to identify contextual antecedents for team learning in professional service firms. Design/methodology/approach: Structural equation modelling was applied to establish reliability and validity and to measure the size of relationships. Evidence was drawn from an empirical sample of 210 consultants in the Nordic professional service industry. Findings: The findings of this study reveal and strongly support that two important contextual antecedent factors that facilitate for team learning in professional service firms are market orientation and leader support for collaborative learning practices. The effect of leader support on team learning is also mediated by a market orientation. Originality/value: There is a paucity of knowledge on contextual factors that contribute to team learning. This study provides insight of theoretical and practical value.

The aspect-based sentiment analysis of hotel reviews represents a critical yet underexplored area of research. Such reviews encompass a range of expressions that extend beyond simple positive, negative, or neutral sentiments, delving into specific aspects discussed within the review. For instance, a statement like 'the location is comfortable, the food is good, but unfortunately, the service is bad' encapsulates multiple aspects, including location, food, and service. Existing research in Aspect-Based Sentiment Analysis (ABSA) frequently employs word embedding techniques for feature extraction, utilizing both Term and Transformer models. This study introduces an innovative approach by transitioning from word to sentence embedding, employing the SBERT transformer model for this transformation. This study further innovates label creation and topic modeling by integrating Bayesian search clustering with Inverse Document Frequency (IDF) calculations. This approach enables the identification of relevant topics, categorizing IDF scores based on occurrence frequencies. Scores ranging between 4–6 are marked as having low value but high informative potential, making them suitable candidates for label-specific datasets, particularly those without pre-existing labels. Additionally, this study incorporates the BigBird model to enhance this classification methodology. Applying this comprehensive framework to hotel review datasets, the result of the ABSA evaluation achieved an impressive accuracy score of 99%, indicating the efficacy of the proposed methodology in this nuanced field.

Abstract Spondyloepimetaphyseal dysplasia with severe short stature, RPL13-related (SEMD-RPL13), MIM#618728), is a rare autosomal dominant disorder characterized by short stature and skeletal changes such as mild spondylar and epimetaphyseal dysplasia affecting primarily the lower limbs. The genetic cause was first reported in 2019 by Le Caignec et al., and six disease-causing variants in the gene coding for a ribosomal protein, RPL13 (NM_000977.3) have been identified to date. This study presents clinical and radiographic data from 12 affected individuals aged 2–64 years from seven unrelated families, showing highly variable manifestations. The affected individuals showed a range from mild to severe short stature, retaining the same radiographic pattern of spondylar- and epi-metaphyseal dysplasia, but with varying severity of the hip and knee deformities. Two new missense variants, c.548 G>A, p.(Arg183His) and c.569 G>T, p.(Arg190Leu), and a previously known splice variant c.477+1G>A were identified, confirming mutational clustering in a highly specific RNA binding motif. Structural analysis and interpretation of the variants’ impact on the protein suggests that disruption of extra-ribosomal functions of the protein through binding of mRNA may play a role in the skeletal phenotype of SEMD-RPL13. In addition, we present gonadal and somatic mosaicism for the condition.

Silaging can be used as preservation technology to valorize currently discarded raw material into protein hydrolysate on board deep-sea vessels. The aim of this study was to investigate the effect of sorting and raw material freshness on the quality and yield of protein hydrolysates obtained through silaging of saithe (Pollachius virens) viscera. Additionally, the effect of using acid-containing antioxidants was tested. Out sorting of the liver prior to silaging resulted in slightly higher hydrolysate yields. The hydrolysates with the highest protein contents were obtained from silages made from fresh raw materials (day 0), and the content decreased significantly after longer storage of the raw material (2–3 days at 4 °C). Storage of the raw material for 1 day did not affect the quality. However, a significantly higher degree of hydrolysis (DH), content of free amino acids (FAA), and total volatile basic nitrogen (TVB-N) were obtained when raw materials were stored for 3 days. The FAA composition was influenced by the raw material’s freshness, with increases in free glutamic acid and lysine and a decrease in free glutamine after longer storage. None of the studied parameters were significantly affected by out sorting of liver or the addition of antioxidants. Overall, the results indicate that the whole fraction of the viscera can be utilized without reducing the quality of the hydrolysate and that the raw material should be stored for a maximum of 1 day prior to preservation to optimize the quality.

Utilization of fish rest raw material for fish oil extraction has received interest with the increasing demand for sustainable food sources. Enzymatic hydrolysis is an efficient method for the extraction of value-added compounds, but its effectiveness may be enhanced by high-pressure processing (HPP). However, HPP can induce lipid oxidation, affecting the quality of the oil. This study aimed to evaluate the quality of fish oil obtained after enzymatic hydrolysis of a mixture of rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar) rest raw material pretreated by HPP. Six pretreatments were tested prior to enzymatic hydrolysis; 200 MPa × 4 min, 200 MPa × 8 min, 400 MPa × 4 min, 400 MPa × 8 min, 600 MPa × 4 min, and 600 MPa × 8 min. The oil samples were analyzed for lipid oxidation parameters, free fatty acid content, fatty acid composition, and color changes over 8 weeks. The results confirmed that HPP may induce lipid oxidation and revealed significant influence of HPP parameters on lipid oxidation, with higher pressures leading to increased oxidation. Fatty acid composition varied among samples, but it was not substantially affected by HPP.

Angrep og trusler mot journalister er utfordringer som påvirker pressens ytringsfrihet og handlingsrom. Utenriksjournalister jobber ofte i konfliktsoner med store sikkerhetsutfordringer. Tidligere forskning viser at kvinnelige journalister møter flere utfordringer enn sine mannlige kollegaer i felt. Samtidig er det flest mannlige journalister som blir drept på jobb. Hvilke tanker gjør dagens yngre utenriksreportere seg om kjønn og sikkerhet i utenriksarbeidet? Gjennom kvalitative dybdeintervjuer undersøker vi empirisk hvilke utfordringer utenrikskorrespondentene møter, og om, og i hvilken grad, de finner at kjønn har betydning for arbeidet deres. Artikkelen konkluderer med at det er behov for et mer sammensatt syn på kjønn og beskyttelse i journalistikken. En slik tilnærming må kombinere det menn og kvinner opplever som forskjellige utfordringer i felt, samtidig som den utfordrer et essensialistisk syn på kjønn som forsterker stereotype kjønnsroller og forventninger til sårbarhet.

Fileting is a popular form of processing methods and in addition to being sold fresh or frozen, filets are used for preparation products battered and breaded filets. This generates considerable amount of side streams like skin, frames, and cut-offs which forms around 30–70% of the total body weight. The European Waste Framework Directive 2008 and recent amendments [EU WFD (2018/851)] stipulates comprehensive regulations which the manufacturers must follow while handling the side streams generated during the processing. This demands a detailed compilation of information regarding the yield, classification and valorization potential of side streams associated with the fileting operations of the cold-water finfishes. The side streams are a rich source of proteins including structural proteins like collagen and biominerals such as hydroxyapatite which find multiple application in food and pharmaceutical industry. Previously, the recovery of these components was performed by extensive chemical treatment with acids or bases, including subsequent washing steps. Nowadays, green extraction methods, defined as technologies with reduced energy and chemical consumption, should be considered to achieve a green shift in the food industry. Nevertheless, industrial upscaling of green extraction methods and subsequent refinement of the isolated compounds must be further evaluated and improved in order to achieve a green shift in food industry by using side-stream derived compounds as ingredients. Moreover, legislations as well as national and international regulations must be considered and evaluated. Even though a number of articles are recently available regarding seafood side stream valorization, this review focus on side streams generated predominantly from cold water fish species and also discusses sustainable green technologies to be included during the recovery process.

IntroductionFish rest raw material generated from the fish processing industry may be a useful resource for recovery of added value compounds. The application of non-thermal novel technologies can improve the extraction. High-pressure processing (HPP) has long been used for the preservation and extension of the shelf life of seafood. It also constitutes a promising technology for the increased recovery of valuable compounds, such as lipids and proteins. The objective of this study was to assess the yield and the chemical composition of the fractions obtained after enzymatic hydrolysis on a mixture of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) rest raw material pretreated by high-pressure (HP).MethodsSix different pretreatments were applied prior to enzymatic hydrolysis; 600 MPa x 8 min, 600 MPa x 4 min, 400 MPa x 8 min, 400 MPa x 4 min, 200 MPa x 8 min, 200 MPa x 4 min.Results and discusssionThese applied pretreatments did not yield higher oil extraction compared to the control. However, the fish protein hydrolysates (FPH) contained higher amount of protein when compared to the FPH obtained from the control.

This scientific paper aims to investigate the best machine learning (ML) for predicting the corrosion inhibition efficiency (CIE) value of amino acid compounds. The study applied a quantitative structure–property relationship (QSPR) model based on an ML approach to predict the CIE values of three new amino acid compounds, namely L-asparagine (LA), L-isoleucine (LI), and L-proline (LP). The result is that the Gradient Boosting Regressor (GBR) model is proven to be the best predictive model based on the coefficient of determination (R2) and root mean square error (RMSE) metrics used. The study found that the three amino acid compounds LA, LI, and LP tested had high CIE values, ranging from 90.49% to 93.67%. These results are also relevant to the CIE values resulting from experimental studies and show a trend that is by the adsorption energy trend. This engineering breakthrough can be used to predict the corrosion inhibition properties of new compounds before experimental synthesis.

Abstract In this work, we developed a QSAR model using the K-Nearest Neighbor (KNN) algorithm to predict the corrosion inhibition performance of the inhibitor compound. To overcome the small dataset problems, virtual samples are generated and added to the training set using a Virtual Sample Generation (VSG) method. The generalizability of the proposed KNN + VSG model is verified by using six small datasets from references and comparing their prediction performances. The research shows that for the six datasets, the proposed model is able to make predictions with the best accuracy. Adding virtual samples to the training data helps the algorithm recognize feature-target relationship patterns, and therefore increases the number of chemical quantum parameters correlated with corrosion inhibition efficiency. This proposed method strengthens the prospect of ML for developing material designs, especially in the case of small datasets.

Lumpfish (Cyclopterus lumpus) is an underutilized marine resource that is currently only being exploited for roe. Lumpfish skin was pre-treated with alkali (0.1M NaOH) and acid (0.1M HCl) at a skin to chemical ratio of 1:10 for 24 h at 5 °C to remove non-collagenous proteins and minerals. The pre-treated skin was washed, and gelatine was extracted with 0.1M of acetic acid at three different ratios (1:5, 1:10, and 1:15), time (12,18, and 24 h), and temperature combinations (12, 28, and 24 °C). The highest total extraction yield (>40%) was obtained with combinations of extraction ratios of 1:15 and 1:10 with a longer time (24 h) and higher temperature (18–24 °C). The highest gelatine content was obtained with an extraction period of 24 h and ratio of 1:10 (>80%). SDS-PAGE analysis confirmed the presence of type-I collagen. A rheological evaluation indicated melting and gelling temperatures, gel strength, and viscosity properties comparable to existing cold-water gelatine sources.

Protease-activated receptor 4 (PAR4) (gene F2RL3) harbors a functional dimorphism, rs773902 A/G (encoding Thr120/Ala120, respectively) and is associated with greater platelet aggregation. The A allele frequency is more common in Black individuals, and Black individuals have a higher incidence of ischemic stroke than White individuals. However, it is not known whether the A allele is responsible for worse stroke outcomes. To directly test the in vivo effect of this variant on stroke, we generated mice in which F2rl3 was replaced by F2RL3, thereby expressing human PAR4 (hPAR4) with either Thr120 or Ala120. Compared with hPAR4 Ala120 mice, hPAR4 Thr120 mice had worse stroke outcomes, mediated in part by enhanced platelet activation and platelet-neutrophil interactions. Analyses of 7,620 Black subjects with 487 incident ischemic strokes demonstrated the AA genotype was a risk for incident ischemic stroke and worse functional outcomes. In humanized mice, ticagrelor with or without aspirin improved stroke outcomes in hPAR4 Ala120 mice, but not in hPAR4 Thr120 mice. P selectin blockade improved stroke outcomes and reduced platelet-neutrophil interactions in hPAR4 Thr120 mice. Our results may explain some of the racial disparity in stroke and support the need for studies of nonstandard antiplatelet therapies for patients expressing PAR4 Thr120.

Biopreservation using lactic acid bacteria (LAB) is a promising technology to prevent the growth of pathogenic microorganisms in fresh and mildly processed food. The main aim of this study was to select LAB, originally isolated from ready-to-eat (RTE) seafood, for biopreservation of fresh salmon and processed salmon products. Ten LAB strains (five Carnobacterium and five Leuconostoc) were selected based on previously demonstrated bioprotective properties to investigate their antimicrobial mechanisms and temperature-dependent growth kinetics in a sterile salmon juice model system. Furthermore, five strains (three Carnobacterium and two Leuconostoc) were selected to test process-dependent growth kinetic parameters relevant to the secondary processing of salmon. Two strains (Carnobacterium maltaromaticum 35 and C. divergens 468) showed bacteriocin-like activity against Listeria innocua, while inhibitory effect of cell-free supernatants (CFS) was not observed against Escherichia coli. All selected strains were able to grow in sterile salmon juice at tested temperatures (4, 8, 12 and 16 °C), with specific growth rates (μ) ranging from 0.01 to 0.04/h at 4 °C and reaching a maximum population density of 8.4–9 log CFU/ml. All five strains tested for process-dependent growth kinetic parameters were able to grow in the range of 0.5–5% NaCl and 0.13–0.26% purified condensed smoke (VTABB and JJT01), with inter- and intraspecies variation in growth kinetics. According to the temperature-dependent growth kinetics and antimicrobial assay results, two strains, Leuconostoc mesenteroides 68 (Le.m.68) and C. divergens 468 (C d.468), were selected for in situ test to validate their ability to grow in vacuum-packed fresh salmon at 4 °C. Both strains were able to grow at maximum growth rates of 0.29 ± 0.04/d for Le. m.68 and 0.39 ± 0.06/d for C.d.468, and their final concentrations were 7.91 ± 0.31 and 8.02 ± 0.25 log CFU/g, respectively. This study shows that LAB, originally isolated from RTE seafood, have promising potential as bioprotective strains in fresh and processed salmon products.

The intention of this article is from a phenomenological perspective to “unpack” the role of emotions when teaching practice-based subjects in higher education. When teaching practice-based subjects, educators’ embodied expressions and personal understanding affect both teachers’ and students’ knowledge production. The academic and the political worlds have a vested interest in understanding and improving methods of teaching and learning in higher education, and concepts such as accountability and performativity are used to indicate quality in education, whereas the affective and embodied knowledge tend to be unterminated. In this article, the authors investigate the teacher’s body as a knowledge producing and productive resource in teaching practice-based subjects. Analysis of the dialogue between two teachers shows how expressing the intersubjective and subjective dialogues in- and between them illuminates qualities such as daring to be a bodily perceptive and emotional being, listening within and the experience of teaching and learning simultaneously, trusting bodily sensations, and letting the students be who they are. By applying theoretical concepts to teachers’ descriptions of classroom experiences, this article contributes perspectives and sheds light upon human knowledge in professional relations.

Due to the continuous growth of the world population, there is an urgent need to find sustainable sources of high-quality protein. Fish side streams rich in essential nutrients and accounting for 60–70% of the whole fish, represent a sustainable source for recovery of valuable protein compounds. The present study aimed at extensive characterization of physicochemical, antioxidant and techno-functional properties of fish protein hydrolysate (FPH) obtained from farmed rainbow trout (Oncorhynchus mykiss). The FPH was produced from a minced rainbow trout raw material by enzymatic hydrolysis performed at 50 °C with addition of 0.05% w/w papain and 0.05% w/w bromelain. After inactivation of the proteases at 90 °C for 10 min, the content of the bioreactor was centrifuged, and the soluble protein fraction (FPH) was collected and freeze-dried. The total protein content of the FPH with 17.24% degree of hydrolysis was high (88.9%) and mainly represented by water-soluble proteins, while the lipid content was below 1%. In addition to the high protein content, trout hydrolysate had low protein oxidation values characterized by a relatively low total carbonyl content together with high amount of thiol groups (3.64 ± 0.31 and 20.7 ± 0.6 nmol/mg protein, respectively). No glass transition was detected in the differential scanning calorimetry (DSC) heat flow curves, suggesting lack of unfreezable solution formation in the FPH at freezing temperatures. The viscosity of FPH showed typical Newtonian behaviour. A peptidomic investigation (using HPLC-MS/MS technique) displayed chemical composition of the trout hydrolysate and identified peptide sequences which are present in the hydrolysate mixture, as well as proteins to which each peptide belongs to. In conclusion, it was suggested to use the obtained trout hydrolysate as a functional ingredient in the food and nutraceutical industry.

The main objective of this study was to investigate how the freshness of saithe (Pollachius virens) viscera affected the quality, composition and yield of oil obtained by silaging. Minced viscera with and without liver were stored separately for up to 3 days at 4 °C before silaging at pH 3.8 for 6 days at 10 °C. An antioxidant mixture was added to evaluate the effect on the lipid oxidation. Oil was extracted thermally from untreated raw material during storage (day 0–3) and after silaging. For oil obtained after silaging of viscera with liver, the oil yields increased significantly when the raw material was stored for more than one day prior to the treatment. Use of fresh raw material (collected at day 0) led to significantly lower oxidation compared to longer raw material storage. After one day of storage, the oxidation was less dependent on the freshness. Silaging with antioxidants resulted in significantly lower formation of oxidation products compared to acid without antioxidants and the most significant differences were observed after one day of storage. Contents of docosahexaenoic acid (DHA) and total omega-3 fatty acids decreased significantly when the raw material was stored for 1–3 days prior to silaging compared to fresh raw material. Results obtained by high resolution nuclear magnetic resonance (NMR) spectroscopy indicated that oxidation of esterified DHA might explain the DHA decrease. The free fatty acid content was highest when fresh raw material was used and was most likely affected by the formation of cholesteryl esters observed in NMR spectra after longer storage. The study shows that although the oil quality is reduced during silaging, processing shortly after catch and use of antioxidants can optimize the quality resulting in less oxidized oil richer in omega-3 fatty acids.