• Rosenkilde Ulriksen opublikował 5 miesięcy, 1 tydzień temu

    Pseudomonas lundensis and Brochothrix thermosphacta are key spoilage microorganisms in aerobically stored chilled meat. The present study aimed to investigate the physicochemical and metabolomic profiles of refrigerated ground beef inoculated P. lundensis (PL) and B. thermosphacta (BT) as mono- or co-culture (BP). P. lundensis was the dominant spoilage strain in the co-culture of ground beef. A large amount of TCA-soluble peptide, TVB-N and TBA were formed in the PL and BP, while acetion was mainly produced in the BT, as accompanied by the different sensory and color changes. Meat metabolome indicated that 95, 396, and 409 metabolites with significant differences, were identified in ground beef inoculated BT, PL, and BP, respectively. These differential metabolites covered 58 metabolic pathways, in which histidine metabolism was identified as an important pathway related to spoilage in the three groups. Specifically, creatine, inosine, anserine, uracil, alanine, glutamine, 3-methylhistidine and 3-hydroxycapric acid were enriched as potential spoilage biomarkers. Taken together, those findings reveal the complex and competitive interactions of their co-culture of B. thermosphacta and P. lundensis, which provided a comprehensive insight into microbial spoilage mechanism in chilled beef.The fruit nutrigenomics is an interesting and important research area towards nutrition enhancement. The phytic acid is one of the major antinutrient compound, present in seeded fruits and crops. It hinders the absorption of iron (Fe), zinc (Zn), magnesium (Mg), potassium (K) and calcium (Ca), causing mineral deficiencies. In the present study, the BsPhy gene was overexpressed in the cucumber fruits using the tomato fruit specific E8 and constitutive CaMV 35S promoter. The E8 promoter imparted heterologous expression of GUS gene in cucumber fruits, furthermore, the fruit specific expression of E8 promoter with BsPhy gene was confirmed in transgenics (E8BsPhy) using anti rabbit-phytase antibody. The physio-biochemical analysis of transgenics revealed, maximum phytase activity in E8BsPhy cucumber fruits at 10 days after anthesis (DAA) compared to 35SBsPhy and wild-type (WT) fruits. Consequently, E8BsPhy fruits also showed increased amount of inorganic phosphorus (Pi), total phosphorus (P), minerals (Zn, Fe, Mg, K, Ca), total carotenoid and other macronutrients at 10 DAA compared to 35SBsPhy fruits. The metabolite profiling of fruits (10 DAA) showed increased sugars, amino acids, sugar acids and polyols, in both E8BsPhy and 35SBsPhy transgenics suggesting higher phytate metabolism, compared to WT fruits. Interestingly, both the transgenic fruits showed higher fruit biomass and yield along with improved nutritional quality, which can be attributed to increased P and Zn contents in transgenic fruits, compared to WT fruits. Our findings reveal that the BsPhy gene enhances minerals and macronutrients in transgenic cucumber fruits making it nutritious and healthy.Esters of 3-monochloro-1,2-propanediol (3-MCPDE), 2-monochloro-1,3-propanediol (2-MCPDE), and glycidyl esters (GE) are processing contaminants that can be found in refined edible fats and oils. Recently, the European Commission has implemented maximum limits for the presence of free and bound 3-MCPDE in vegetable fats and oils and in marine and fish oils. This boosted the necessity of oil producers to develop refining methods to limit the concentration of both 3-MCPDE and GE in their final products. Physical refining may lack the potential to mitigate the formation of 2- and 3-MCPDE. Therefore, in this study, the chemical refining method were explored to provide a viable mitigation strategy aimed at industrial application. Several pilot plant treatments with organic palm oil were performed. The investigated refining methods included a neutralization, a water washing process, reduced deodorization temperature, and a combination of them. The best performing chemical refining treatment achieved a final concentration of 0.42 (-49%), 0.78 (-52%), and 0.99 (-73%) mg/kg for 2-MCPDE, 3-MCPDE, and GE in organic palm oil, respectively. Results thus showed chemical refining has great potential for the simultaneous mitigation of 2-, 3-MCPDE, and GE.Selenium is an essential trace element for human and animal health, and an appropriate amount of Se can promote the growth and development of plants. Cabbage is a popular cruciferous vegetable with a good ability to accumulate Se, and Se-enriched cabbage can be used as an important Se source for humans. However, the effects of Se-enriched cultivation and the Se accumulation mechanism in cabbage are still unclear. In this study, the effects of different concentrations (0, 0.1, 0.2, 0.4, 0.8, and 1.6 mmol/L) of selenate on cabbage growth and quality were explored. A low concentration of selenate (0.1 mmol/L) promoted growth and nutritional quality. The contents of total Se, S, selenocystine, and selenomethionine significantly increased following selenate application. Important secondary metabolites, namely glucosinolates, phenolic acids, and flavonoids, participate in the response to selenate in cabbage. Comparative transcriptome and metabolomics analysis revealed that SULTR2.2, SULTR3.1, APS, APK2, HMT, MMT, and NTR2 played important roles in Se absorption and conversion. Additionally, the SUR1, UGT74B1, and ST5b genes and cytochrome P450 family genes CYP83A1, CYP79A2, and CYP79F1 may be the crucial genes in the glucosinolates biosynthesis and regulation pathway. The PAL, 4CL, CAD, CHS3, FLS, and CYP73A5 genes were involved in flavonoid and phenolic acid accumulation under selenate treatment. These results reveal the internal relationships in the regulatory network of Se metabolism and secondary metabolite biosynthesis in cabbage and help further the understanding of the physiological and molecular mechanism of how Se biofortification affects cabbage quality, thereby providing genetic resources and a technical basis for the breeding and cultivation of Se-enriched cabbage with excellent nutritional quality.The importance of single-cell variability is increasingly prominent with the developments in foodborne pathogens modeling. Traditional predictive microbiology model cannot accurately describe the growth behavior of small numbers of cells due to individual cell heterogeneity. The objective of the present study was to develop predictive models for single cell lag times of Salmonella Enteritidis after heat and chlorine treatment. A time-lapse microscopy method was employed to evaluate the single cell lag time by monitoring cell divisions. Four supervised machine learning algorithms including gradient boosting regression tree (GBRT), artificial neural network (ANN), random forest (RF), and support vector regression (SVR) were applied and compared. Results show that all four machine learning models have good predictive capabilities without an overfitting of the data. The ANN approach demonstrated superior prediction performance over other machine learning models (RMSE 0.209, MAE 0.135 and R2 0.989). Furthermore, the SHapley Additive exPlanation (SHAP) measures were used to capture the influence of each feature on the model output, and results revealed that population lag times and sublethal injury rate have dominant impacts on the single cell lag time. Consequently, the findings generated from this study may be useful in managing the potential food safety risk caused by single cells of foodborne pathogens.As one of the major non-conventional edible legumes, different cultivars of pigeon pea have different uses according to their specificity. For the first time, the main phenotype and plant physiological parameters of ten different pigeon pea cultivars were evaluated in detail, and then a novel method using UPLC-QqQ-MS/MS has been investigated for the qualitative and quantitative analysis of eighteen active constituents originating from pigeon peas. After systematic optimization of MRM parameters, the developed method showed a good precision (RSD less then 7.28%) and high recovery (91.27-113.62%) within 6 min. It was found that pigeon pea 11Y21, R7 and R10 exhibited superiority in contents of the unique active compounds of cajaninstilbene acid, cajanuslactone, longistylin A and longistylin C. Moreover, combined with the main plant physiological parameters, we can find that excessive plant growth may affect the metabolites content in pigeon pea. Meanwhile, the gene expression levels indicating that the metabolite profiles of different cultivars can be strongly influenced by genetic variation. Overall, the present work developed a valid method for the detection of various phenolic compounds, which could be applied for applicability and variety breeding of pigeon pea and also providing sufficient evidences for other utilization in the future.The strong-flavor Baijiu (SFB) brewing workshop is a complex ecosystem with diverse microbiomes. As a potential source of microbiomes in fermentation, microbiota in the environmental microecology may affect the quality and flavor of SFB. Here, we report the collection of environmental microecological samples from three SFB workshops with different usage times (named 70a, 30a, and new, respectively). We used 16S rRNA and internal transcribed spacer (ITS) gene amplicon full-length sequencing to explore the microbial community structure in SFB. The SourceTracker tool was used to investigate links among fermentation samples, raw materials, and the environment and decipher the construction process in the workshop indoor environment. Lactobacillus acetotolerans was the most important bacterial genus in Zaopei after fermentation, whereas other types of samples exhibited different prokaryotic community structures. The composition of the fungal community was similar, with Saccharomycopsis fibuligera, Debaryomyces hanstrol of spontaneous fermentation.Word association (WA) is a projective and powerful technique that consists of the spontaneous generation of words from specific stimuli. This technique is used in sociology and psychology studies; however, in the Consumer and Food Science area has gained importance since it allows to explore beliefs, expectations, or attitudes in the context of food consumption behavior. The aim of this work is to present a current status on the use of this technique in the studies of food consumption behavior. A narrative review of the literature was carried out with articles published in four databases ScienceDirect, Wiley Online Library, Emerald Insight, and Taylor & Francis. Seventy-four articles that show the use of the WA technique in different cultures were selected. WA technique has been applied in different countries, however, it has been primarily used in Latin America. WA has been applied mainly to decipher consumers’ perceptions towards different aspects of food, although some works show that WA serves to understand beliefs, expectations, impressions, attitudes, and even to conceptualize different categories of food from the language of consumers. Some theoretical and methodological implications are discussed regarding the use and application of this projective technique.Double W1/O/W2 emulsions can act as fat substitutes in food matrices, although synthetic emulsifiers are commonly used due to their inherent instability and susceptibility to coalescence. In order to guarantee the stability of the W/O interface, the synthetic emulsifier polyglycerol polyricinoleate (PGPR – 4.5% w/w) was used. However, the replacement of chemically synthesized ingredients by natural alternatives has been extensively pursued in food applications. In this sense, whey protein isolate (WPI) and sodium caseinate (SC) were used to stabilize the external aqueous phase (W2) of water-in-oil-in-water double emulsions (W1/O/W2), in addition to Tween 80 that was used as a control. The composition of the internal aqueous phase and its effects on the double emulsion were studied by the addition of sodium chloride (0.2% w/w NaCl), gallic acid (0.5% w/w GA) or a GA/NaCl mixture (0.5% / 0.2% w/w). The effect of these different hydrophilic components was evaluated from measurements of droplet size, viscosity, ζ potential, interfacial tension and kinetic stability.

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