European Food Research and Technology最新文献

The objective of the study was the development of nonconventional restructured freeze-dried multicomponent snacks obtained with the addition of chokeberry pomace powder (CP) supported by calcium ions (0, 0.01 and 0.05%). The study consisted of the evaluation of the impact of various quantities (1, 3 and 5%) of dried chokeberry pomace powder on selected physicochemical characteristics compared to snacks structured by pectin (0.5 and 1.5%). The results showed that the application of CP caused a significant reduction in the snacks’ water content and activity, which could contribute to enhanced stability. Hygroscopic properties and porosity also decreased with increasing quantity of CP, which was a consequence of structural changes in the material. The CP addition elevated the hardness of the snacks, however the effect was notably lower than after pectin incorporation. The use of the CP promoted the bioactive compound content and antioxidant activity of the freeze-dried snack. Total phenolic and anthocyanin contents elevated with the increasing quantity of CP, also followed by antioxidant activity improvement. The introduction of anthocyanins, which are red colorants, also caused notable changes in the color of the products. Overall, the application of chokeberry pomace resulted in obtaining an innovative snack option characterized by fortified bioactive compounds content and antioxidant activity. However, more research is needed to optimize also nutritional characteristics of the products.

Bacillus cereus is a spore-forming foodborne pathogen that causes emetic and diarrheal food poisoning. An emetic strain of B. cereus produces spores and an emetic toxin called cereulide, which exhibits high heat resistance. In this study, we investigated the effects of epigallocatechin gallate (EGCg), theaflavin-3’-gallate (TF2b), and theaflavin-3,3’-gallate (TF3), polyphenolic components of tea extracts, on the survivability, spores, and toxin of B. cereus. Among them, EGCg at 62.5 μg/mL and 250 μg/mL showed bacteriostatic and bactericidal effects on B. cereus by damaging the cellular membrane, causing leakage of cellular nucleic acid related substances, and thus inhibiting the growth of B. cereus. However, no significant effects were shown on spore germination by EGCg, TF2b, or TF3 at a concentration of 250 μg/mL in this investigation. Their inhibitory effects were primarily confined to the outgrowth of daughter cells after spore germination. Furthermore, quantitative polymerase chain reaction (qPCR) showed that they suppressed the activity of cesA, a gene associated with cereulide production. At concentrations of 125 µg/mL for TF2b and 62.5 µg/mL for TF3, a discernible attenuation of cytotoxic effects induced by cereulide on HEp-2 cells was evident.

The application of anthocyanins as red colorants in lipid-containing foods such as oil-in-water emulsions is challenging due to their ability to act as antioxidants and their instability under various environmental conditions. In this study, we investigated the kinetics of black carrot anthocyanin degradation and the subsequent color loss influenced by lipid oxidation reactions in 1% (w/w) flaxseed oil-in-water emulsions stabilized by 0.1% (w/w) sodium dodecyl sulfate (SDS) at pH 2 upon storage at 35 °C for ten days under light and in the dark. Oxidatively stable Miglyol oil-in-water emulsions and SDS solutions were used as reference. The results showed simultaneous formation of lipid hydroperoxides and degradation of anthocyanins. The addition of anthocyanins decreased lipid hydroperoxide formation, confirming the antioxidant activity of anthocyanins through radical scavenging mechanism. The kinetic modelling of lipid oxidation and anthocyanin degradation are particularly important for estimating color stability in colored emulsion-based food systems such as dairy or non-dairy milk or yoghurt drinks.

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The objective of this study was to assess the antioxidant activity and phenolic compounds of bee bread samples obtained from various regions in Türkiye The goal was to characterize and classify 15 of bee bread samples based on their geographical origins. This investigation employed chemometric techniques, specifically principal component analysis (PCA) and a hierarchical clustering algorithm (HCA), for the inaugural comprehensive analysis of all data encompassing antioxidant activity and phenolic compounds in bee bread. The primary objective was to unveil potential clustering patterns among of bee bread samples based on their geographical origins. According to the results, the Total Phenolic Content (TPC) of bee bread samples ranged from 4.393 to 14.917 mg GAE/g dw, while the Total Flavonoid Content (TFC) exhibited variation within the range of 0.681 to 3.504 mg QE/g dw. p-OH benzoic and p-coumaric acids were detected in all samples. Other phenolic compounds were identified in different proportions among the bee bread samples. This study demonstrated the successful application of the PCA chemometric method to assess the antioxidant activity and phenolic compounds of bee bread samples from various regions of Türkiye. The results revealed effective clustering of the bee bread samples based on their geographical origins.

Graphical Abstract

Background: Salmonella, is one of the most important pathogens causing foodborne illnesses worldwide. The early detection of Salmonella is essential to minimize the risk. Herein, the nanoprobe (CS-AuNPs@phage-T156) for Salmonella was obtained by functionalizing cysteamine (CS) stabilized gold nanoparticles (CS-AuNPs) with phage T156. Results: In the presence of target Salmonella, the CS-AuNPs@phage-T156 specifically recognized and adsorbed on the surface of Salmonella, then induced the aggregation of gold nanoparticles and the color changes from red to purple, which enabled visual detection. The concentration of Salmonella was quantified by the absorption ratio (A₆₈₀/A₅₂₆), with a wide linear range from 1.2 × 10¹ CFU/mL to 1.2 × 10⁶ CFU/mL. Under the optimal experimental conditions, this assay possessed a potent selectivity characteristic quickly toward Salmonella, with a detection limit of 12 CFU/mL. Conclusion: This simple and rapid detection method is expected to provides a novel identification element for the detection of Salmonella by intuitive visualization judgment and quantitative analysis.

The general objective of this study was to assess the processing impact of selected advanced and conventional thermal technologies on the microbiological quality and selected physical and chemical parameters of blackcurrant juice (Ribes nigrum L.). In addition, the juice was extracted using an innovative spiral filter press operating under a low-oxygen atmosphere and vacuum pressing of the juice. Obtained blackcurrant juice was treated with selected technologies at a pilot scale: pulsed electric fields (PEF, 90 kJ/l, 15 kV/cm), high hydrostatic pressure (HHP, 400 MPa, 1 min), and thermal treatment (74 °C, 3 s). The processing effects were investigated directly after the treatments and during 8 weeks of refrigerated storage at 4 ± 1 °C. Different technologies and storage time affected mostly parameters like concentration of sugars, vitamin C, antioxidant capacity, total phenolic content, and total anthocyanins. The overall effect of PEF and HHP under the investigated conditions has had only a minor impact on selected quality parameters of the blackcurrant juices compared to the thermal treatment.

The comprehensive characterization of floral honeys enables a deeper understanding of their chemical composition and biological potential, which improves the market value of these honeys. This study evaluated in ten Brazilian commercial floral honeys the physicochemical characteristics (moisture, water activity, free acidity, pH, glucose, fructose, and sucrose, 5-(hydroxymethyl) furfural, diastase activity, color intensity, and electrical conductivity), aliphatic organic acids, mineral elements, phenolic compounds, antioxidant activity, and visible spectrophotometric profile. All the honey had differences (p < 0.05) in the physicochemical parameters, but were under international legislation. Gluconic acid was the major organic acid (134.62 ± 0.99–2254.35 ± 126.77 mg 100 g⁻¹), K was the major mineral (184.92 ± 13.71–2271.23 ± 1.63 mg kg⁻¹), and abscisic acid was the major phenolic compound (4.12 ± 3.12 µg g⁻¹–79.62 ± 12.68 µg g⁻¹). Eucalyptus honey presented the highest antioxidant activity, followed by multifloral and Escallonia spp. (canudo-de-pito) honey. Eucalyptus and canudo-de-pito honeys were distant from the other honey samples in the principal components analysis scatterplot (65.21% of the variability of the data explained). These findings contribute to the knowledge of the composition and quality of the floral honeys evaluated.

The present work aimed to analyse the bioactive compounds and antioxidant activities of peel and seed extracts obtained from three tropical fruits: papaya, mango, and loquat, with different solvents (water, ethanol, and water:ethanol, 1:1) and evaluate their potential effects as antioxidants in a cooked chicken model under refrigerated storage. In the seed and peel extracts produced, bioactive compounds (total phenolic compounds, total flavonoids, and condensed tannins) were quantified. Additionally, antioxidant activities (ABTS, DPPH, and FRAP) were assayed spectrophotometrically. Seed extracts from the three fruits were selected for application in a cooked chicken model in which colour, lipids, and protein oxidation were evaluated during refrigerated storage. Moreover, compared with the other extracts, the mango seed extracts (MSEs), irrespective of the extraction solvent used, had the highest contents of bioactive compounds and antioxidant activities. MSEs significantly reduced the CIE L* and increased the CIE a* while effectively controlling lipid and protein oxidation in cooked chicken models during refrigerated storage. Due to their high antioxidant activity and high concentration of phenolic compounds, flavonoids, and condensed tannins, MSEs are interesting sources of natural antioxidants and bioactive compounds for use in the meat industry.

This work aims to determine the effect on the aromatic profile and phenolic content of red wine vinegars produced by surface culture at two different temperatures (30 °C and 37 °C) and using different inocula of acetic acid bacteria (Acetobacter malorum, Gluconobacter oxydans and a mixture of bacteria isolated from a Sherry vinegar). Fifty-seven volatile compounds and 23 polyphenolic and furfural compounds were identified. Vinegars obtained at 37 °C had poorer volatile profiles, with no significant influence of the strain of acetic bacteria. For polyphenolic content, temperature was also the most significant variable, so that the vinegars produced at higher temperatures had lower total anthocyanin contents, while no clear trend was observed regarding the influence of temperature on the low-molecular-weight phenolic constituents. The total tannin content in the vinegars obtained experienced slight increases after acetification, although this was not affected by temperature, and it was observed that when using the mixture of acetic acid bacteria from the Sherry vinegar, the total tannin content was significantly higher than when individual bacteria cultures of Acetobacter malorum or Gluconobacter oxydans were used. Temperature appears as a key parameter for the volatile and phenolic composition of red wine vinegar versus the use of different acetic acid bacteria.