Food Technology and Biotechnology最新文献

Research background: Recently, natural ingredients have come to the fore instead of synthetic additives in meat and meat products. In this context, the use of propolis extracts, a natural bee product, prepared with different solvents is quite widespread. From this perspective, this study investigates the contribution of ethanolic extract of propolis on the shelf life of beef meatballs and the extent to which it maintains the quality characteristics of the samples during storage at 4 °C.

Experimental approach: In this study, an ethanolic extract of 0.1, 0.3, 0.5 and 1 % of propolis was added to meatball samples. After preparation, the samples were packaged and stored at 4 °C. During storage, the meatball samples were subjected to physicochemical, microbiological and sensory analysis.

Results and conclusions: The addition of propolis did not affect significantly the water activity values. However, significantly lower pH values were observed during prolonged storage, especially in the samples containing higher amounts of propolis. The addition of propolis also effectively delayed oxidation and there was an amount-dependent decrease in TBARS values. The use of propolis in the preparation of meatballs did not have a significant effect on the initial CIELab parameters of the samples, but changes in a* and b* values ​​were observed at the end of storage compared to the control sample. A significant increase in the total phenolic content as well as the DPPH˙ and ABTS⁺ radical scavenging activities of the meatballs was observed depending on the propolis amount. Considering the results of microbiological analysis, it was found that propolis could increase the microbiological quality of the meatballs, but the addition of more than 0.5 % propolis affected the overall acceptability of the samples.

Novelty and scientific contribution: As a result, the addition of certain amounts of propolis was found to be a potential alternative to synthetic counterparts that could be used to preserve refrigerated meatballs to delay oxidation and microbial spoilage without affecting the sensory properties of the samples.

Research background: Ectoine is a desirable molecule with high application potential, particularly in the cosmetics and pharmaceutical industries. The current production method uses microorganisms that require high salinity. Therefore, purification of the product is expensive, complex and requires appropriate equipment. To overcome these obstacles, we were looking for new moderately halophilic, ectoine-producing bacteria.

Experimental approach: The bacteria were isolated from high-salinity environments: in the vicinity of Tyrawa spring, in Złockie near the Na Mokradłach spring and in Rajcza, all in Poland. Their ability to biosynthesise ectoine and additionally hydroxyectoine in a 10 % premixed seawater environment was assessed semiquantitatively using mass spectrometry (MS). The growth of the bacteria was also compared under these conditions. The most promising strains were then identified based on 16S rDNA sequence and their morphological, biochemical and physiological properties were described. The ectoine was biosynthesised based on the collected data and the preferences of individual strains. The concentrations of the final product were determined by HPLC. After the screening process, the most suitable strain was identified.

Results and conclusions: Fifty-six bacterial strains were isolated. Most strains produced insignificant amounts of ectoine or hydroxyectoine in the presence of 10 % salt. However, ten strains, all isolated from the Tyrawa spring, showed promising properties and were used in further studies. Based on the 16S rDNA sequence, four were identified as Halobacillus sp., two as Virgibacillus sp. and one as Bacillus sp., Pseudalkalibacillus sp., Salimicrobium sp. and Thalassobacillus sp. The basic biochemical and physiological properties as well as the ability to grow in the presence of NaCl, KCl, (NH₄)₂SO₄ and MgSO₄ were described. Ectoine was biosynthesised following the best parameters estimated for each strain. Based on the results, Virgibacillus salarius BHTA19 was identified as a new potential producer of ectoine.

Novelty and scientific contribution: We isolated a promising ectoine producer, moderately halophilic bacterium - Virgibacillus salarius BHTA19. BHTA19 is a wild-type strain that produces significant amounts of ectoine in environments with moderate salt concentrations. It has great potential and the possibility of industrial application.

Research background: Gluten contamination is the main concern of those who follow a gluten-free diet. Although rice is naturally gluten-free, previous studies have identified gluten contamination of rice that can occur during processing, storage, handling or cooking. As a result, consumer confidence may be affected, emphasising the need to examine how these concerns shape their risk perceptions and influence their subsequent decisions. This study aims to evaluate: (i) the perceived risk of gluten contamination among gluten-free diet followers and (ii) the actual presence of gluten contamination in commercially available rice on the Croatian market.

Experimental approach: This cross-sectional study combined survey methods and laboratory analysis. An online questionnaire was used to assess the perceived risk of gluten contamination in rice among individuals following a gluten-free diet (N=66). The presence of gluten in forty-one samples of white, brown and parboiled rice from six producers on the Croatian market was then analysed using an enzyme-linked immunosorbent assay (ELISA).

Results and conclusions: Laboratory assays failed to detect gluten in any of the rice samples (limit of quantification 5 mg/kg), yet 54 (82 %) respondents expressed high uncertainty about the risk of gluten contamination in rice. These results show a significant discrepancy between consumer perception and scientific evidence. They emphasise the need for improved communication and clearer labelling to build consumer trust and support informed dietary choices.

Novelty and scientific contribution: This study highlights the gap between the perceived and actual risk of gluten contamination in naturally gluten-free food and emphasises the importance of addressing consumer concerns through better education and transparent product information.

Research background: Cactus pear (Opuntia ficus-indica) is an excellent source of polysaccharides and bioactive compounds with remarkable health benefits. The mucilage of the cactus pear, which consists mainly of water and complex carbohydrates, has properties similar to gum due to its unique physiological properties. Recently, plant-derived mucilage has gained significant attention in the dairy industry for its potential as a natural thickening and colloidal stabilizing agent.

Experimental approach: This study investigates the use of freeze-dried cactus pear cladode pulp from Opuntia ficus-indica L. Miller as a source of mucilage and its interaction with a commercial stabilizer on the physical properties of low-fat cocoa ice cream (3.0 % fat). The study evaluates the influence of cactus pear cladode pulp on the physicochemical properties and technological parameters of the ice cream. Ice cream samples containing 1.0, 1.5 and 2.0 % cactus pear cladode pulp were compared with a control sample (without cactus pear cladode pulp).

Results and conclusions: The results show that cactus pear cladode pulp is rich in fiber and phenolic compounds and has significant technological potential due to its water absorption capacity (WAC), water solubility index (WSI) and oil absorption capacity (OAC). The addition of cactus pear cladode pulp lowered the pH of the ice cream, improved its darkness and yellowness, increased the overrun and delayed the melting process. These results suggest that cactus pear cladode pulp works synergistically with the commercial stabilizer, highlighting its potential as a natural fat substitute and stabilizer for low-fat ice cream formulations.

Novelty and scientific contribution: This study represents pioneering research into the use of freeze-dried Opuntia ficus-indica cladode pulp in the production of ice cream. The results offer valuable insights for the ice cream industry and provide a natural alternative for stabilizers and fat substitutes.

Research background: Chronic, unregulated inflammation is a crucial factor in the development of numerous diseases and is closely linked to the increased expression of cyclooxygenase-2 (COX-2). While various bioactive peptides from marine organisms have shown COX-2 inhibitory effects, peptides derived from the collagen of the peanut worm (Siphonosoma australe) have not yet been demonstrated. The aim of this study is to investigate the potential COX-2 inhibitory activity of peanut worm collagen by simulated digestion in vitro with pepsin-pancreatin followed by molecular docking.

Experimental approach: During simulated in vitro digestion, commercial pepsin (at pH=3) and pancreatin (at pH=7.5) were applied for 240 min at 37 °C to evaluate the degree of hydrolysis, peptide concentration and COX-2 inhibitory activity. The samples with the most significant COX-2 inhibitory activity were then separated into fractions and identified.

Results and conclusions: The 210-minute simulated digestion in vitro showed the highest COX-2 inhibitory activity (64.31 %). This result was confirmed by the increased degree of hydrolysis (DH) and peptide concentrations observed during the simulated in vitro digestion. The peptide fraction of <1 kDa had the highest inhibitory activity (89.05 %) and was subsequently subjected to sequencing analysis. Three novel peptides, ADIAGQAAQVLR, LNNEITTLR and VGTVEK, were identified and confirmed to contain crucial amino acids and therefore verified as COX-2 inhibitors. VGTVEK has the most potent interaction, as shown by the lowest binding energy (-4.41 kcal/mol). The molecular docking revealed that VGTVEK (631.35 Da) binds to the active site of COX-2 and forms hydrogen bonds with Gln178, Leu338, Ser339, Tyr371, Ile503, Phe504, Val509 and Ser516 and hydrophobic interactions with Met99, Val102, Val330, Ile331, Tyr334, Val335, Leu345, Trp373, Leu517 and Leu520. Other biological activities of the produced peptides included ACE inhibitors, dipeptidyl peptidase-IV (DPP-IV) inhibitors and α-glucosidase inhibitors. After toxicity prediction, the peptides were classified as non-toxic.

Novelty and scientific contribution: The study found that peptides derived from peanut worm collagen have the potential to be novel, natural agents for anti-inflammatory therapy. Their broader application in functional foods, nutraceuticals and pharmaceuticals could provide new options for people suffering from inflammation and support both treatment and maintenance of overall health.

Research background: Dandelion flowers have a very short shelf life. The canning process is known not only to stabilise food and preserve its nutritional content at a high level, but also to significantly extend its shelf life. For this reason, canned dandelion flowers are believed to be beneficial for both consumers and the gastronomy sector.

Experimental approach: In this study, fresh dandelion (Taraxacum officinale L.) flowers were canned using sucrose syrup with different (20 and 30) degrees of Brix (°Bx) as filling medium and stored at 25 °C for 30 days. A total of 56 phytochemicals were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS), while the in vitro antioxidant activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and cupric reducing antioxidant capacity (CUPRAC) and the total phenolic content (TPC) were analysed in both the canned flowers and the syrup at different storage times (on days 10, 20 and 30).

Results and conclusions: The antioxidant activities of fresh dandelion flowers were 89.6 % and 0.8 mmol Trolox equivalents (TE) per gram, respectively. The lowest DPPH (41.4 %) and CUPRAC expressed as TE (0.3 mmol/g) activities were observed on day 20 in samples stored in the 30 °Bx syrup. The TPC in fresh flowers, expressed as gallic acid equivalents (GAE) per g of extract, was 367.4 mg/g. The highest TPC in canned flowers was determined on day 10 in the samples in syrup with both °Bx. LC-MS/MS analysis identified 24 phytochemicals in fresh flowers, including quinic acid, luteolin, siranoside, chlorogenic acid, fumaric acid, caffeic acid, protocatechuic acid, quercetin, cosmosiin, isoquercitrin and apigenin. A decrease in the polyphenol content of canned flowers was observed during storage. The results indicate that canning dandelion flowers in a 30 °Bx syrup and storing them for 20 days preserved their phenolic content and antioxidant capacity.

Novelty and scientific contribution: Numerous studies in the literature focus on extending the shelf life of fruit and vegetables by the canning method. However, this study fills a gap in the literature by successfully applying the canning technique to edible flowers for the first time. Furthermore, the results of this study contribute to future research on the potential commercialisation of canned dandelion flowers as a food product.

Research background: The main problem regarding the authenticity of fish meat lies mainly in misleading labelling or substitution of species, like the replacement of valuable fish meat with species of lower value or species originating from illegal fishing. For these reasons, the need has arisen for adequate analytical methods to detect food fraud.

Experimental approach: The aim of this study is to differentiate six fish species-carp, mackerel, pike, pollock, salmon and trout-based on differences in their protein composition using two mass spectrometry methods. Matrix-assisted laser desorption/ionization-time ff flight mass spectrometry (MALDI-TOF MS) was employed to identify characteristic species-specific m/z values to differentiate raw and cooked fish meat. Additionally, liquid chromatography-electrospray ionization-quadrupole-time tf flight (LC-ESI-Q-TOF) was used to determine specific amino acid sequences in carp and salmon, selected as model species.

Results and conclusions: Distinct species-specific m/z markers were identified for all six fish species, enabling their differentiation in both raw and processed form. In carp and salmon, hundreds of peptide sequences were detected, leading to the identification of a panel of peptide markers that determine both the fish species and the type of meat processing. The results confirm that mass spectrometry-based proteomic approaches can serve as effective tools for the authentication of fish meat.

Novelty and scientific contribution: This study shows that it is possible to use two complementary mass spectrometry techniques for reliable and rapid authentication of fish species. The identification of specific peptide markers and species-specific m/z values contributes to the improvement of food authenticity control and provides a powerful approach to the detection of fish meat adulteration.

Research background: Silver nanoparticles (AgNPs) were synthesised using agricultural waste and green synthesis, a sustainable alternative to traditional synthesis techniques that require hazardous chemicals and extensive processing. The AgNPs were produced using spent coffee (Coffea robusta) grounds and rice (Oryza sativa) husks, both common agricultural wastes rich in bioactive substances such as proteins, flavonoids and phenolic acids that act as natural reducing agents.

Experimental approach: The formation and stability of AgNPs were confirmed using various methods. UV-Vis spectroscopy showed surface plasmon resonance (SPR) peaks at 450 nm, indicating the formation of AgNPs, while Fourier transform infrared spectroscopy (FTIR) identified functional groups responsible for the bio-reduction and stabilisation of the nanoparticles. X-ray diffraction spectroscopy (XRD) confirmed the crystalline, face-centred cubic structure. Zeta potential analysis showed a stable dispersion and particle size analysis showed a consistent size distribution. The antibacterial activity of AgNPs was evaluated by testing their effectiveness against both Gram-positive and Gram-negative bacteria.

Results and conclusions: The AgNPs were synthesised using spent coffee grounds and rice husks, which are rich in biomolecules that serve as effective reducing and stabilising agents. FTIR analysis identified functional groups involved in the reduction and stabilisation of nanoparticles, while XRD confirmed their face-centred cubic (FCC) crystalline structure. Zeta potential measurements showed stable dispersions with particle sizes of AgNPs obtained using spent coffee grounds of approx. 187 nm and of AgNPs obtained using rice husks of 198 nm. The synthesised AgNPs also showed strong antibacterial activity against both Gram-positive and Gram-negative bacteria.

Novelty and scientific contribution: AgNPs were obtained by green synthesis using agricultural waste such as spent coffee grounds and rice husks as natural reducing and stabilising agents. This study highlights the innovative use of biomolecule-rich materials to generate stable AgNPs with strong antibacterial properties and provides a sustainable basis for further development of nanotechnological applications.

Research background: The almond beverage enriched with flaxseed is an important source of α-linolenic acid (ALA), an essential omega-3 fatty acid that the human body cannot synthesize and must obtain it through the diet. Although omega-3 fatty acids are essential for all people, this beverage is particularly beneficial for those who do not consume fish, such as vegans and vegetarians, as it is a plant-based source of ALA. Its versatility allows it to be easily incorporated into different recipes and daily meals. Therefore, this study aims to optimize a plant-based almond beverage enriched with flaxseed, offering a natural and completely vegan source of omega-3 fatty acids.

Experimental approach: The initial formulation of the drink comprised 75 % raw almonds and 25 % flaxseed mixture, water (in 1:6 ratio) and 4 % sweetener. Following preliminary tests, the beverage was optimized using the mixing method to determine the ideal proportions of the ingredients. This process resulted in 16 samples, each with different minimum and maximum amounts of each ingredient, which were replicated and analyzed. One of the formulations achieved an optimal mass fraction of 4.27 mg/g of omega-3 fatty acids and a viscosity of 6.03 mPa^.s. The physicochemical properties, bioactive compounds, fatty acid composition and lipid profile of the optimized beverage were evaluated.

Results and conclusions: The addition of flaxseed had a significant effect on the lipid profile and increased the alpha-linolenic acid content in the beverage by 1960 times, eventually reaching 3.92 %. This optimization enriched the beverage with omega-3 fatty acids and improved the concentration of antioxidants and carotenoids. Importantly, these improvements did not significantly affect the color and viscosity of the final product, creating an affordable option that can benefit the vegan and vegetarian community.

Novelty and scientific contribution: This study shows that the response surface model effectively identified the ideal composition for the beverage, leading to an optimized formulation of a plant-based drink. This composition could have promising applications in the food industry.

Research background: Biodegradable packaging is gaining immense research interest as conventional non-biodegradable food packaging has led to significant environmental pollution. In response to this, this study aims to develop biodegradable films based on polyhydroxyalkanoate (PHA) as potential food packaging material.

Experimental approach: Polyhydroxyalkanoate (PHA) homopolymer, poly(3-hydroxybutyrate) [P(3HB)] and copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)], known microbial biodegradable biopolymer plastics, were layered in different mass ratios using the dispersion coating technique over the brown kraft paper as a food packaging material. PHA are known to be safe, non-cytotoxic and non-genotoxic, with a remarkable ability to biodegrade in the environment. The P(3HB) and P(3HB-co-3HV) were synthesised from carbon sources of palm olein and a combination of palm olein with 1-pentanol, respectively, using Cupriavidus malaysiensis USMAA2-4_ABH16, a transformant bacterial strain with acquired lipase genes.

Results and conclusions: Contact angle analysis indicated that brown kraft paper coated with P(3HB-co-3HV) had a higher contact angle than uncoated brown kraft paper and paper coated with P(3HB). The biodegradation analysis of brown kraft paper coated with P(3HB) showed that it degraded 100 % within 9 days compared to all samples of brown kraft paper coated with P(3HB-co-3HV), which were completely degraded by day 12.

Novelty and scientific contribution: The results show that brown kraft paper coated with P(3HB-co-3HV) was more hydrophobic than uncoated and P(3HB)-coated brown kraft paper. This study encourages further investigations of brown kraft paper coated with PHA to develop biodegradable food packaging, paving the way for a sustainable alternative to non-biodegradable packaging material.