Food Biophysics最新文献

In the present study, pearl millet varieties (ProAgro 9444 and HHB 67) with different amylose contents were used to synthesize starch nanocrystals (SNCs) through acid hydrolysis. The obtained SNCs were incorporated as nanofillers into starch-based nanocomposite films at varying concentrations (0–20%). The films were characterized for their mechanical, barrier, morphological, structural, thermal, and biodegradable properties. Control starch films, prepared without SNCs, exhibited tensile strengths of 4.31 MPa (ProAgro 9444) and 2.96 MPa (HHB 67). Maximum tensile strength (TS) and minimum water vapor permeability (WVP) were achieved at 7.5% SNC loading for ProAgro 9444 (12.56 MPa, 2.45 × 10⁻¹⁰ gPa⁻¹s⁻¹m⁻¹) and at 10% for HHB 67 (12.12 MPa, 2.31 × 10⁻¹⁰ gPa⁻¹s⁻¹m⁻¹) (p < 0.05). Elongation at break decreased in nanocomposite films compared to controls, dropping from 53.12% to 17.88% for ProAgro 9444 films and from 62.77% to 20.34% for HHB 67 films. Morphological analysis revealed no phase separation in nanocomposites up to 7.5% and 10% SNC incorporation, respectively. The nanocomposites exhibited A- and Vh-type crystallographic patterns with higher crystallinity than control films. Thermogravimetric analysis indicated enhanced thermal stability in SNC-containing nanocomposites. All films biodegraded in a three-stage process, with ProAgro 9444 nanocomposites showing the highest weight loss (97.39%), followed by HHB 67 nanocomposites (94.34%). Overall, SNCs and amylose content demonstrated a synergistic effect in enhancing the functional properties of starch-based nanocomposite films.

Drying and moisture sorption in bananas present ongoing challenges, especially in terms of providing accurate storage recommendations and minimizing drying time. This study aimed to investigate the moisture sorption isotherms and drying kinetics of bananas. Moisture sorption was analyzed using the static gravimetric method with saturated solutions, covering a water activity range of 0.14–0.88, and at incubation temperatures of 30, 40, and 50 °C. The models used in this study included Peleg, Oswin, Halsey, Brunauer–Emmett–Teller (BET), Guggenheim–Anderson–de Boer (GAB), and Courie. Statistical analysis showed that the Peleg model performed best. A comparison between the Peleg model and an Artificial Neural Network (ANN) revealed that the conventional Peleg model provided more accurate predictions. The Peleg model produced a sigmoid-shaped sorption curve. As temperature increased, the number of sorbed water monolayers, the sorption surface area, the percentage of bound water, and the monolayer moisture content all decreased. The thickness of the bound water monolayer and the pore radius ranged from 0.32 to 0.95 nm and 176.23–4981.34 nm, respectively. Field emission scanning electron microscopy (FESEM) revealed that the surfaces of dried bananas developed cracks, which facilitated a faster adsorption process. Energy dispersive spectroscopy (EDS) analysis showed that the surface of dried bananas was primarily composed of carbon (63%) and oxygen (35%). Higher temperatures accelerated the reduction in moisture content, with the average drying rate ranging from 0.12 to 0.15%d.b./min. The total color difference, volume of the visible object, and shrinkage were observed in the ranges of 45.92–48.49%, 40.26–47.54%, and 52.46–59.74%, respectively. The FTIR curve revealed distinct wavelengths for each type of bond. Based on the relationship between equilibrium moisture content (EMC) and water activity, dried bananas are recommended to have a safe moisture content of 14.94–16.85% (d.b.) during storage. Furthermore, the suggested drying time at temperatures between 40 and 60 °C ranges from 1800 to 3540 min.

Cocoa contains polyphenols that offer potential health benefits. However, the processing of cocoa beans often leads to a reduction in their polyphenol content. This study aimed to evaluate the antioxidant and methylxanthines profiles of chocolates made from cocoa beans fermented with specific yeast starter cultures: Pichia kudriavzevii (PK) (MH979681), Hanseniaspora thailandica (HT) (MH979675), and a combination of both (mix). Fermentation with HT or PK significantly influenced the process, producing less acidic beans, which impact the levels of catechin and epicatechin in the resulting chocolate. Additionally, chocolate made from beans fermented with HT or PK displayed higher concentrations of caffeine and theobromine, respectively. The highest caffeine level was found in HT-fermented chocolates, whereas PK-fermented chocolates showed the highest theobromine content compared to the control and Ghana chocolates. HT and PK are suggested as promising yeast starters for producing chocolates with enhanced methylxanthines profiles, offering potential for the development of functional and health-oriented chocolate products.

In order to analyze the formation mechanism and explore the potential applications of Canna starch and its derivatives (Canna Starch OSA Ester (CSOE)) and Canna Starch Phosphate Ester (CSPE)), the samples were subjected to an environment of iodine. The resulting complex was analyzed using small angle X-ray scattering and fluorescence (SAXS and XRF). The findings revealed that CSPE exhibited the highest binding capacity (5.19% at aw 0.15; 25.03% at aw 0.99). Interestingly, iodine tended to accumulate within the hilum rather than the periphery of the starch particles, resulting in smoother surfaces. Furthermore, it was observed that the process of octenylsuccinylation and phosphorylation caused a shift in the scattering peak towards higher values in the SAXS graphs, indicating a shorter lamellar repeat distance (CSPE, 9.52 nm; CSOE, 8.16 nm). These results have the potential to advance characterization techniques and contribute to the development of applications involving amylose-restrained materials.

Oral films (OFs) are versatile platforms that combine efficacy, ease of administration, and adsorption. The plant Crescentia cujete L. has shown bioactivity for respiratory applications. In this study, fruit pulp extracts obtained under different conditions (ripening stage, pulp pretreatment, and extraction method) were incorporated into gelatin/carboxymethyl cellulose (CMC) matrices to evaluate their influence on film properties. Extracts from freeze-dried pulp using the Soxhlet showed the highest flavonoid (8.7 ± 0.8 mg quercetin/g extract) and phenolic content (28.4 ± 2.4 mg gallic acid/g extract), strong antioxidant capacity against the ABTS^•⁺ radical (EC₅₀ = 19.0 ± 0.2 μg/mL). The agar diffusion method confirmed antibacterial activity against the oral bacterium S. mutans. Films with 0–7% extract were produced by casting and analyzed by physicochemical, morphological, thermal, mechanical, and FTIR methods. Increasing extract concentration modified visual appearance (b* parameter), phenolic content (7.8 ± 0.5 mg GA/g), contact angle (~ 16°), and disintegration time (~ 29 s), while thickness (0.05 ± 0.01 mm), moisture content (11.9 ± 0.9%), and antibacterial activity remained unchanged. SEM showed homogeneous morphology, and the extract addition decreased the melting temperature (~ 14 °C). Mechanical testing revealed the highest Young´s modulus at 6% extract (3716 ± 168 MPa). Release studies indicated that films with 6% and 7% of the extract fit Higuchi and First-order models, respectively. These results demonstrate the feasibility of developing plant-based OFs with tailored release profiles and therapeutic potential.

Packaging is essential in food production, particularly for red meat, which is vulnerable to spoilage because of its high protein and fat contents. This study explored the use of polylactic acid (PLA)/chitosan-based films integrated with the medicinal plant Astragalus tragacantha and biosynthesized copper nanoparticles (CuNPs) to increase the shelf-life of red meat and sausage. The green-synthesized CuNPs (32 nm, PDI 0.15) and PLA-chitosan nanoparticles (131 nm, PDI 0.41) were characterized via proton nuclear magnetic resonance (¹H-NMR), dynamic light scattering (DLS), and polydispersity index (PDI), confirming uniform dispersion and enhanced crystallinity in the composite films. HPLC identified key phytochemicals in A. tragacantha extract that contribute to its antioxidant and antimicrobial properties. Films with 500 µL/mL A. tragacantha and 0.3 mg/mL CuNPs exhibited superior performance: reduced water vapor permeability (6.41 g.mm/m².day.kPa), high tensile strength (25.13 MPa), and potent antioxidant activity (DPPH assay). Antimicrobial tests revealed synergistic effects against Escherichia coli, Salmonella enteritidis, and Staphylococcus aureus, with inhibition zones 20–30% greater than those of the individual components. In meat and sausage applications, these films maintained the optimal pH, reduced volatile nitrogen bases (16 mg/100 g in meat after 7 days; 31.5 mg/100 g in sausages after 60 days), and minimized lipid oxidation (peroxide value: 1.25 meq/kg on day 1). The composite films outperformed sodium nitrite in preserving freshness, demonstrating their potential as eco-friendly alternatives for extending shelf-life and ensuring meat safety. The integration of phytochemicals and nanotechnology offers a sustainable solution to replace synthetic preservatives in food packaging.

Intelligent indicator films were successfully fabricated by incorporating blood peach anthocyanins (BPA) and β-cyclodextrin-encapsulated carvacrol (β-CD@CAR) into chitosan/cellulose nanocrystals (CN) matrices. The prepared films were comprehensively characterized using multiple analytical techniques. The addition of BPA and β-CD@CAR significantly enhanced the films' UV–vis radiation blocking ability, thermal stability, as well as antioxidant (DPPH radical scavenging rate: 45.89% for CN-EO-1A film, vs. 7.71% for pure CN film) and antibacterial activities ​(inhibition zones of 10.24 mm and 8.52 mm against Escherichia coli and Staphylococcus aureus, respectively). Specifically, β-CD@CAR notably improved the mechanical properties of the films and strengthened their color stability and pH responsiveness. Notably, the CN film with 0.5% (w/w) BPA and β-CD@CAR (CN-EO-0.5A) demonstrated excellent performance, with a tensile strength of 10.99 MPa and an elongation at break of 91.66%. Additionally, it exhibited remarkable color responsiveness to different pH values and ammonia exposure.​ The effectiveness of the CN-EO-0.5A in monitoring shrimp freshness during storage at 4 °C was further evaluated. The film could visually indicate the freshness levels of shrimp, distinguishing among fresh, sub-fresh, and spoiled states through distinct color changes. Strong correlations were established between the total color difference of the CN-EO-0.5A and key freshness indicators of shrimp, including total volatile basic nitrogen (R² = 0.9630) and total viable count (R² = 0.9983). Therefore, the CN-EO-0.5A film showed promise for real-time monitoring seafood freshness.

Dynamics model for polysaccharide (HNCVP) extraction process from Nostoc commune Vauch was established. The process was fitted with the second Fick’s law, and exhibited a spontaneous and exothermic process. A maximal HNCVP yield was obtained under temperature of 363.15 K, extraction time of 150 min and solid-liquid ratio of 1:50 g/mL. The apparent viscosity of HNCVP affected significantly by pH and the type and intensity of ions, and increased significantly with the increase of Na⁺ and K⁺ concentration, while significant decreased after the addition of Ca²⁺ and Zn²⁺. In addition, HNCVP can inhibit the proliferation of Bovine Viral Diarrhea Virus (BVDV) by interference with 5’ UTR gene synthesis, and protection cells growth by regulating the relatively expression of IRF-1 and IRF-3 in Madin-Darby bovine kidney cells, where interferon maybe activated for virus elimination and defense. These results presented the potential of HNCVP as a functional additive in the food and pharmaceutical industries.

In this study, green coffee powder (GCP) was used as a source of dietary fiber and antioxidants in beef burgers stored under refrigeration for 7 days. The effects of GCP on the color, dietary fiber content, oxidative stability, sensory and textural properties of the burgers were evaluated. Additionally, the polyphenolic composition, total phenolic and flavonoid contents, antioxidant activities, and molecular docking analyses of GCP were performed. Green coffee powder contained high levels of bioactive compounds, particularly caffeic acid (724 mg/100 g), caffeine (754 mg/100 g), and chlorogenic acid (321.1 mg/100 g). Results such as DPPH radical scavenging activity (82.98%), total phenolic content (662.99 mg GAE/100 mL), total flavonoid content (144.63 mg CE/100 mL) and FRAP value (133.03 nmol Fe(II)/g) supported the strong antioxidant potential of GCP. The addition of GCP significantly increased the dietary fiber content of beef burgers. On day 7, the lowest TBARS values were observed in the GCP1 (3% green coffee powder added beef burger), GCP2 (6% green coffee powder added beef burger) and GCP3 (10% green coffee powder added beef burger) groups (0.65, 0.68, and 0.81 mg MA/kg sample, respectively), while the control group showed the highest value (1.96 mg MA/kg sample), indicating improved oxidative stability. Ferulic acid showed superior pharmacokinetics with high absorption and bioavailability, while chlorogenic acid had limited absorption and low bioavailability. Molecular docking studies with the 5IKQ protein target revealed that chlorogenic acid had the strongest binding affinity (− 9.4 kcal/mol) and formed multiple stabilizing hydrogen bonds. In conclusion, the use of green coffee powder as a natural source of antioxidants and dietary fiber offers a promising, clean-label, and cost-effective strategy to enhance the functional and technological quality of meat products.