Food Biophysics最新文献

Aflatoxins (AFs) are toxic secondary metabolites of filamentous fungi which can reduce the quality of several food commodities like hazelnut and hazelnut products. For the AFs, the data were fitted to polynomial response models using multiple regression analysis, resulting in high coefficients of determination (R² values ranging from 0.8917 to 0.9674) for each type of aflatoxins. The optimal conditions for achieving maximum degradation percentages for total aflatoxins (AFT) and AFB1 were determined to be US power of 80W, enzyme treatment of 2.5 U g sample, and 20 min of US application for 12.5 µg kg AFT conditions after graphical and numerical optimizations. The optimum conditions resulted in 44.33% and 45.58% degradation for AFT% and AFB1 respectively, with predicted values of 43.93% and 44.17% for AFT% and AFB1. The data exhibited that, enzyme treatments were not significant for degradation for AFB1% and AFT%, whereas significant for AFB2 and AFG2. Depending on the initial AFT concentration, more than 50% degradation rate was achieved by current design parameters. Study results indicated that US treatment can alter certain quality parameters of hazelnut paste, including changes in aroma, a decrease in browning index, and a slight increase in peroxide value.

In this study, kefir-containing healthy snacks were produced by using 3D food printing technique. Although kefir has many important health benefits, its consumption is quite low. It was thought that kefir-containing snacks in attractive shapes produced with a 3D food printer could increase the kefir consumption. For this purpose, disintegrated kefir gels prepared with starch, gelatin and alginate were used as inks. First, the minimum gelation concentration (C*) of each gelator was determined. Then, disintegrated gels with concentrations of C*, C*+1%, and C*+2% were prepared with each gelator and the effect of gelator concentration on printing quality was investigated for each gelator. Printing quality was associated with storage modulus, loss factor and flow behavior, and the minimum gelator concentration required for a suitable formulation for 3D printing (highest printability and dimensional stability) was determined as 5%, 6% and 3% for starch, gelatin and alginate, respectively. Lactobacillus spp. and Lactococcus spp. contents of the starch-based sample were found to be significantly lower than those of fresh kefir and gelatin and alginate-based samples. Sensory properties and consumer appreciation were lower for the gelatin-based sample. Due to the high printing quality (98% printability and 99% dimensional stability), high probiotic content (7.81 and 8.13 log cfu/ml Lactobacillus spp. and Lactococcus spp. content, respectively) and high consumer appreciation (4.71 out of 5 for general acceptance), alginate-based sample (containing 3% alginate) was chosen as the best sample. In conclusion, new, chewable, alive, alternative kefir products were successfully developed for consumers seeking new ways of kefir consumption.

In this study, microalgae proteins (Spirulina and Chlorella) were extracted, characterized, and investigated for their potential techno-functionalities. The proteins from the microalgae biomass were extracted by alkaline solubilization followed by iso-electric precipitation. Subsequently, their physicochemical characteristics (microstructure, thermal stability, secondary structure, and crystallinity) and functional properties (protein solubility, water and oil holding capacities, as well as emulsifying and foaming properties) were investigated. Spirulina biomass resulted in a high extraction yield (37%), giving a protein isolate containing 90% of proteins. Both Spirulina and Chlorella protein extracts displayed high thermal stability. FTIR analysis revealed a clear difference in the secondary structure of the protein extracts. A slight difference in microstructure was noted between the two proteins, but both had small particle sizes and uniform dispersity. Spirulina proteins were more crystalline (53%) than the Chlorella proteins (36%). Spirulina showed better functional properties (protein solubility, emulsifying, and foaming properties) compared to Chlorella. We observed that the Spirulina protein had more water-holding capacity than the Chlorella protein, while the latter also showed appreciable oil-holding capacity. These findings suggest that the microalgal proteins could be useful in the food industry.

In this study, we successfully fabricated vanillin (VAN) incorporated poly (ethylene oxide) (PEO) and whey protein isolate (WPI) nanofibers and optimized the preparation conditions. The nanofibers were prepared at different percentages of PEO/WPI/VAN, and the characterization techniques of XRD, FTIR, FESEM, and DSC were employed to analyze the samples. Additionally, mechanical properties, and physicochemical were measured to identify the critical factors for nanofiber optimization. The best parameters observed at a PEO 10%: WPI 3% ratio of 80:20, producing narrower and smoother fibers (average diameter of 264.07 nm; additionally, the addition of VAN to the optimal PEO/WPI ratio (80:20) decreased fiber diameter. Furthermore, vanillin was incorporated into the optimized PEO/WPI nanofibers at concentrations of 1MIC (10 mg/mL) and 2MIC (20 mg/mL) to evaluate their antioxidant and antibacterial abilities before and after electrospinning. In summery, these findings suggest that the PEO/WPI nanofibers, with the addition of VAN, hold potential as a promising platform for future applications in the food and drug industries. Further research can build upon these findings to explore the specific functionalities and applications of these nanofibers in greater detail.

The objective of this research was to obtain and characterize chitosan (CS) based matrices conceived as folic acid (FA) dried reservoir that could find application as food coating upon rehydration. An Argentinean and high molecular weight (MW) chitosan (AC) was used and contrasted with a commercial type one (CC). FTIR and XRD were applied for the polysaccharide-vitamin dried mixed systems characterization. Shifts in bands of FA and AC or CC were observed in the mixed systems, confirming the interaction among the components, for example, the bands at 1382 and 1391 cm^− 1 (AC and FA, respectively) shifted to 1387 cm^–1 in the in AC-FA mixed systems. XRD data showed that the FA is in its protonated form as expected and is maintained in the different mixed systems obtained using either with CC or AC, demonstrating the robustness and applicability of the material to properly conserve the active ingredient.

The ultrastructure and topography were studied by SEM and AFM, respectively. FA incrustations in a self-associated form were observed in the topography images. Variations in topography observed for the AC-FA and CC-FA mixed systems could be attributed to specific interactions between the components and the molecular features of each CS (i.e. the mean particle size was 63 ± 3 and 9 ± 1 nm and, roughness gave values of 0.47 and 0.41 nm, respectively).

Vitamin bioaccessibility remained unchanged compared to the control (88.36% ±10.35%), being equal to 91.08% ± 5.02% for AC-FA and 71.56% ±14.08% for CC-FA, after submitted samples to an in vitro digestion process. In sum, mixed AC-FA systems obtained are promising materials for a possible additional application in coating matrices inspired by biopolymers to improve food preservation, maintaining the bioaccessibility of vitamins.

Konjac glucomannan (KGM) is commonly blended with κ-carrageenan to improve the gel properties of food, which are mostly influenced by KGM purification. Control of ethanol pH for KGM purification is an easy and simple option to modify the properties of KGM, that tends to alter the gel properties of κ-carrageenan/KGM blends. In this study, the effect of ethanol at different pH (ranging from 2.5 to 12.5) on KGM was investigated, and the gels of κ-carrageenan with KGM purified by ethanol at different pH were prepared with microwave heating. With KGM purified with ethanol between pH 5.5 and 9.5, κ-carrageenan/KGM blends exhibited higher gel strength, hardness and water holding capacity than those of gel with native KGM, which was much related with the removal of impurity, the increased viscosity and altered structure of KGM, enhancing the interaction between κ-carrageenan and KGM. Poor gel properties of the blends were observed with KGM purified with ethanol at pH between 2.5 and 4.5 caused by KGM degradation, or at pH 12.5 due to the removal of acetyl groups. Thus, control of ethanol pH during KGM purification can easily and simply optimize the gel characteristics of κ-carrageenan/KGM blends to meet desired application requirements.

The Ilex paraguariensis, known as yerba-mate, is widely consumed as a hot or cold infusion in South America. Every year during the leaves harvesting, a rate of 5 tons/ha of branches is generated due to the tree trimming. The epidermis of these branches (IPC) is characterized by a high concentration of chlorogenic acids. Due to its promising high compound concentration, IPC extract is well-suited for various applications, and its preservation is particularly crucial, especially in bakery goods. This study aimed to optimize the spray-drying encapsulation of IPC extract to enhance the stability of chlorogenic acids for baked product applications. Through multivariate design, the optimal encapsulation conditions were determined, resulting in 75% encapsulation efficiency (%EE), 66.5% loading capacity (%LC), a 41 ºC increase in thermal stability, and particles with an average diameter of up to 5 µm. In sponge cakes formulated with encapsulated IPC extract (IPCE), an average of 94.4% of chlorogenic acids was preserved, compared to only 69.3% when free-IPC extract was used. Furthermore, the chlorogenic acids in IPCE exhibited excellent stability over 12 months when stored at 4ºC. Spray-drying encapsulation proved to be a rapid and effective process for the food industry, preserving chlorogenic acids for at least one year during storage under conditions that would naturally lead to degradation. These findings encourage the application of encapsulates to enhance the functionality of foods and add value to a naturally neglected commercial product.

This study has sought to determine the impact of interfacial dynamics on the in vitro lipid digestion of a commercial infant formula; in particular, the specific role of interfacial proteolysis on the subsequent rates of reaction of droplet lipolysis. A powder infant formula was used as the as a protein-stabilised emulsion substrate during simulated infant gastric digestion at different pH level 3.5, 4.5 and 5.5. The digestate was treated with a fungal lipase and porcine pepsin (used to analogue human gastric lipase and pepsin) respectively and in a combined action. The study found that for fungal lipase treated digestate, the rate and extent of lipolysis were observed to be maxim at pH 5.5, in accordance with the optimal pH activity of the lipase. Findings also indicated that the proteinaceous interface did not appear to act as a barrier to lipolysis, since treatment with lipase and pepsin did not result in any significant increase in extent of lipolysis. However, it was observed that surface proteolysis did lead to alteration of the structural fate of the enzyme during digestion when compared to when the emulsion was digested solely by lipase. Findings suggest that lipolysis under these conditions may be independent of the structural dynamics of the emulsion during digestion, as observed within the context of this study design.

Yogurt is popular among consumers because of its unique flavor and rich nutrition, but the residue of yogurt in the package causes a huge waste of resources and economic losses. To reduce yogurt residues in packaging, a green and safe anti-adhesion coating was assembled using beeswax and modified hydrophobic zinc oxide spray. The water contact angle of the coating reached up to 156.45° and up to 150.64° for yogurt, with a sliding angle of 4.50°, exhibiting good anti-adhesion ability. During actual storage, yogurt adhesion in the package was reduced by 93.73% and the coating had no negative effect on the quality of yogurt. The study showed that a secure anti-adhesion coating that is resistant to acidic environments and refrigeration temperatures and suitable for a variety of material surfaces can be prepared by a simple spraying process, providing a new approach to solving the yogurt adhesion problem.

Legume proteins were utilized in this study to electrospin an bioactive component for use in food packaging. Firstly, the protein extraction from legumes with ultrasound assistance with the use of deep eutectic solvents (UA-DES) has been studied. The optimum extraction conditions were determined. Secondly, lentil protein isolate (LPI) and chickpea protein isolate (CPI) produced by the UA-DES were used in nanofiber production by electrospinning using polyvinyl alcohol (PVA) at different ratios. Lastly, the usability of fibers obtained from protein isolates and PVA in coating bioactive components was tested using ferulic acid (FA). The encapsulation properties of nanofibers produced at a ratio of 50:50 (PVA:PI) were investigated. The characteristic and antibacterial properties and release kinetics of the produced FA-loaded nanofibers were evaluated. The distribution of FA within the fibers was confirmed by fluorescence microscopy. Furthermore, the antibacterial properties were proven and the release kinetics of the produced FA-loaded fibers in different food simulants were determined. As a result, the final encapsulated material obtained by coating FA with nanofibers created with PVA and LPI-CPI mixtures might have suitable properties which may be used in various food applications.