Food Biophysics最新文献

In this study, alkalized cocoa powders were obtained by optimization study with the Mixture Design, which included the use of the main alkali salts (NaOH, KOH and K₂CO₃). The effects of the alkali salt(s) used on the antioxidant activity (DPPH and ABTS methods), total phenolic compounds, particle size distribution, physicochemical (pH, moisture content, water activity, total ash amount, color) and volatile component profiles of samples were investigated. Significant models with high R² values (0.8297–0.9983) were determined for all main alkalization indicators (a*/b*, pH, and TrMP/TMP), color characteristics, Sauter mean (D3:2), bulk and tapped density (p < 0.05). It has been determined that classification based only on pH and color properties in alkalization may cause disadvantages in terms of polyphenol content and aroma profile, which are among the main motivation factors for consumption of cocoa-based products. In addition, the effects of alkalis on stability and technological properties should also be taken into consideration for this process.

The rise in environmental awareness has led to the development of biopolymers-based alternatives to synthetic packaging materials. This disease can be controlled by improving its coating properties. This study investigates the efficacy of zinc oxide nanoparticles (ZnO NPs) incorporated with corn starch as an edible coating to enhance the post-harvest quality of mangoes. Mango samples were coated with varying concentrations of ZnO solutions and stored at ambient temperature for seven days. The findings demonstrate that a 1.5 M ZnO-corn starch concentration is optimal, significantly delaying fruit senescence, minimizing fungal growth, and maintaining sensory quality, resulting in the lowest weight loss percentage of 13.53%. The ZnO NPs- corn starch coating achieved a 97.9% efficiency in preventing decay during storage. Analytical techniques such as XRD, FTIR, and EDX confirmed the presence of ZnO on the mango skin, correlating with increased pH levels and change in total soluble solids (TSS), which indicate reduced respiration rates and preserved titratable acids. FESEM analysis revealed a uniform coating thickness of 21.59 nm, while HPLC analysis showed extended citric acid retention (3.2 min), correlating with prolonged mango quality. This study successfully demonstrates the potential of a non-toxic ZnO NPs-starch nanocomposite coating to improve mango preservation, offering a promising solution for extending the shelf life of mangoes post-harvest.

Graphical Abstract

The bacterial and fungal community structure and diversity of Sauerkraut samples (LPS, GY, AS, ZA, QN (2), QN (1), QXN, KL, YQ, RH, TR, and BJ) obtained from 12 different sampling sites in Guizhou Province were analyzed, as were their physicochemical indices and characteristic volatile constituents, by performing third-generation high-throughput sequencing. The results showed that there were some similarities and differences among the sauerkraut samples from different regions of Guizhou Province. A network correlation analysis revealed stronger interactions among microorganisms in the six regions. Additionally, the results of the redundancy analysis showed that Lactobacillus plantarum was positively correlated with altitude (H). In this study, we evaluated the correlation between microbial diversity and physicochemical indices and volatile components in sliced sauerkraut samples from different regions of Guizhou Province to provide a theoretical basis for mining microbial resources in traditional sauerkraut foods in Guizhou, China.

The development of edible films (EFs) using renewable resources such as gelatin and native corn starch has garnered significant interest due to their potential to enhance food preservation and safety. Combining extrusion with the casting method enhances mechanical and barrier properties by modifying starch and gelatin structures through heat, pressure, and shear. This study aimed to develop, characterize, and optimize the functional properties EFs produced from an extruded formulation of corn starch, gelatin, and glycerol using the casting method. Furthermore, it evaluated the impact of these optimized EFs as coatings on the quality characteristics of the “Kent” mango cultivar. The study factors were gelatin content (GC, 0–10%) and extrusion temperature (ET, 80–120°C). The EFs were characterized and optimized, determining the tensile strength (σ), elongation (ε), water vapor permeability (WVP), and Water Solubility (S), using the surface response methodology. Results showed GC significantly influenced mechanical and barrier properties (P < 0.05), with higher GC increasing σ, ε, WVP, and S. ET also affected mechanical properties (P < 0.05) but not barrier properties (P > 0.05). EFs exhibited σ of 3.14 MPa to 8.34 MPa, ε of 10.55–25.60%, WVP (5.59 × 10^–12 to 6.82 × 10^–11 g m Pa^-1 s^-1 m^-2), and S from 66.29–80.50%. According to the optimization study, the EFs with the best mechanical and barrier properties were obtained using an ET of 80°C and GC of 2.93%. Applied as coatings on ‘Kent’ mango, these EFs significantly extended shelf life and preserved postharvest quality.

This study aimed to develop oil-in-water emulsion gels based on quinoa protein hydrolysates, alginate, and high-oleic sunflower oil, to assess their antioxidant activity, and to evaluate their viscoelastic properties. Quinoa protein concentrate (QPC) was hydrolyzed using alcalase. The resulting quinoa protein hydrolysates (QPH) (DH: 30 ± 4%) were evaluated for their iron-chelating activity and reducing power. The antioxidant capacity of emulsion gels based on QPC or QPH was determined using the ABTS and DPPH methods, and rheological analysis was also performed. The QPH exhibited higher ability to chelate ferrous ions and greater reducing power than QPC. The ABTS and DPPH free radical scavenging activity of the QPH-based emulsion gels was higher than that obtained from QPC-based emulsion gels. Furthermore, QPH was more effective in reducing lipid oxidation. After 30 days of storage, QPH-based emulsion gels showed lower levels of malondialdehyde compared to those obtained from QPC-based emulsion gels. The rheological behavior of the emulsion gels revealed that the storage modulus (Gʹ) was greater than the loss modulus (Gʺ) throughout the entire frequency range, thus deformation in the linear region was mainly elastic. The strain recovery occurred because of the good viscoelastic properties of the samples. Although the strengthening of QPH-based emulsion gels was less than that of the QPC-based gels, the gel structure remained stable through the entire temperature range. Overall, this evidence strongly suggests that quinoa protein hydrolysates can be effectively employed in the development of soft-solid food acting as natural antioxidant sources and preventing lipid oxidation.

This study investigates the incorporation of anthocyanin-rich extracts from Mountain Pepper Berry (MPB) and Queen Garnet Plum (QGP) into pectin-based films to develop pH-sensitive indicators. Using glycerol as an extraction solvent, significant differences in anthocyanin composition were identified: MPB extracts contained a diverse range of anthocyanin species, with a total content of 267.13 ± 5.21 mg L⁻¹, compared to the predominantly cyanidin-based QGP extracts, with 222.14 ± 1.61 mg L⁻¹. Differences in anthocyanin structures were elucidated using UPLC-Q-ToF-MS/MS analysis. FTIR and UV-Vis spectroscopy were used to assess the compatibility of the extracts with pectin and the homogeneity of anthocyanins within the film structure. Mechanical testing revealed that MPB films exhibited superior tensile strength (8.53 ± 0.51 MPa), stiffness (2274 ± 158.64 gmm^− 1), and energy to failure (141.7 ± 16.23 J m^− 3) compared to QGP films, which had lower tensile strength (7.74 ± 0.32 MPa), stiffness (1947 ± 125.82 gmm^− 1), and energy to failure (115 ± 18.81 J m^− 3). Both film types displayed similar moisture content (MPB: 48.89%, QGP: 48.13%) and water vapour permeability, indicating comparable barrier properties. When exposed to volatile ammonia, QGP films showed a more pronounced colour change, attributed to their anthocyanin profile, with a notable shift from red to brown. This research highlights the potential of glycerol-extracted anthocyanins from Australian native fruits as functional additives in pectin films, offering promising applications for intelligent packaging with enhanced mechanical performance and responsive colour-changing properties.

Graphical Abstract

This study investigates the synthesis and characterization of active microcapsules and films using basil seed gum (BSG) and ginger essential oil (GEO). Varied concentrations of BSG wall (1% and 2%) and GEO (0.1%, 0.2%, 0.5%, and 1%) were explored, assessing their effects on antioxidant activity, zeta potential, particle size distribution, encapsulation efficiency (EE), and microstructural features of the microcapsules. Additionally, the impact of these variables on the physicochemical properties of BSG-MGEO films, including colorimetric attributes, mechanical properties, moisture content, water solubility, water vapor permeability (WVP), density, thickness, antibacterial efficacy, microstructural morphology, and thermal behavior, was examined. Encapsulation efficiency of MGEOs with 1% and 2% wall concentration ranged from 44.15 ± 2.86% to 67.06 ± 1.69% and 96.80 ± 0.98% to 97.93 ± 0.59%, respectively. The inclusion of GEO and both concentrations of the wall significantly increased film thickness, water solubility, and WVP compared to the control film (p < 0.05). Elevating GEO concentration led to a significant enhancement in elongation at break (EB), escalating from 19.05 to 39.88%, while an increase in wall concentration to 2% resulted in an EB of 35.04% (p < 0.05). Field emission scanning electron microscopy (FE-SEM) images illustrated that heightened solid content (BSG) in MGEOs preserved stability during film formation and increased film density. Remarkably, films containing 0.5% and 1% GEO, across both wall concentrations, exhibited significant antibacterial activity against Staphylococcus aureus (p < 0.05), with no discernible effect on Salmonella typhimurium.

This is a structural examination of egg-and-lemon sauce (avgolemono), a complex colloidal food which, depending on the stage of preparation and use, is a viscous liquid, an aggregated dispersion, a foam, an emulsion, and a gel. Following the food’s preparation, the pH-dependent zeta potential and phase equilibria/separations are discussed as principal contributors to the extensional rheology and to the relaxation times of its macromolecular components. Foaming under whipping is discussed along with the topology of the foam’s interface. These are used to understand the foam stability of the sauce, as it undergoes structural (foaming), compositional (addition of yolk), and chemical changes (acidification by lemon juice). The effect of the above on the shear rheology of the bulk phase and of the foamed product are used as to explain its foaming ability and stability. The foams are examined as to highlight the fine interplay of the dual character created by the bubble collapse and the liquidification during the recipe’s preparation. The temperature changes during the making and the application of the sauce, as well as cases of the recipe’s mismanagement (e.g. overheating), are discussed in terms of thermodynamics and structure.

Pimenta dioica (L.) or Allspice leaves is a spicy leaf and its bio-actives, nutrient and therapeutic value, is under-exploited. In this study, the leaves were dehydrated by sun (SD), shade (SHD), cross-flow (CFD), freeze (FD), low temperature low humidity (LTLH), and vacuum (VD) drying. Our focus extended beyond mere kinetics to explore the chemometrics, volatiles and bioactivity of the leaves. Modified page and Lewis models exhibited a superior fit in describing the dehydration process with high R² value (0.98 – 0.99), lower χ² and RMSE, with effective moisture diffusivity ranging from 0.26 × 10⁻⁹ to 7.47 × 10⁻⁹ m²/s. SEM exemplifies the matrix of leaf microstructures. FD and CFD retained highest total polyphenol content (70.67 ± 2.13 and 65.58 ± 1.95 mg GE/g), total flavonoid content (61.58 ± 0.95 and 43.34 ± 1.23 mg RE/g), essential oil yield (3.62 ± 0.01 and 3.23 ± 0.02%), volatiles (94.47% and 99.83%) and antioxidant activities (109.43 ± 1.15 mg TE/g and 105.88 ± 2.51). GC–MS analysis revealed eugenol, β-myrcene, chavicol, limonene and 3-octenol as a major compounds and Principal Component Analysis were explained 82.2% of the data variation in volatile compounds. Although effective, FD’s cost-effectiveness is challenging. Conversely, CFD emerged as a more economically viable option, preserving essential nutrients such as ash, protein, carbohydrates, fiber, vital multi-minerals, and intrinsic bioactive components. This study pioneers the exploration of Allspice leaves, unlocking promising avenues in the spice industry for diverse applications. It highlights the need to optimize dehydration methods to preserve nutritional content and bioactive properties, paving the way for further advancements in spice processing technologies.

Graphical Abstract

Strawberries are highly perishable, leading to significant postharvest losses and reduced fruit quality during storage and distribution. Conventional preservation methods are often insufficient, necessitating the development of innovative and natural approaches to improve the longevity and quality of these fruits. This study investigates the use of sericin, chitosan, and Aloe vera blended formulation (SBF) coating to extend the shelf life and quality of strawberries. The coated strawberries were stored at 14 ± 1 °C and 40–45% humidity, with their properties monitored over 12 days. Scanning electron microscopy (SEM) and fourier transform infrared (FTIR) spectroscopy analyses of strawberries confirmed the uniform application and chemical interaction of the coating, while contact angle measurements demonstrated improved wettability (contact angle 50.73 ± 0.6 °). The SBF coating significantly reduced weight loss and maintained higher firmness i.e. with only 7 ± 1.14% weight loss resulted after 9 days compared to a 16.5 ± 0.7% weight loss in uncoated strawberries. It also preserved higher levels of total soluble solids and titratable acidity compared to uncoated strawberries. Additionally, the SBF coating effectively slowed moisture loss, prevented infection, and regulated pH and respiration rate, demonstrating its potential for postharvest preservation of strawberries.