Food Biophysics最新文献

Plant-derived anthocyanins are widely used as natural food colorants, with rambutan peels representing a potential source. However, their application is limited because of their inherent instability and susceptibility to rapid color changes. Copigmentation and encapsulation present promising strategies to increase both the stability and color intensity of anthocyanins. This study aimed to improve the stability and color intensity of anthocyanins extracted from rambutan peels through copigmentation and encapsulation. Rambutan peels were blanched, dried, and ground into powder before being subjected to ultrasound-assisted extraction via 0.2% citric acid in 96% ethanol. Copigmentation was conducted by adding Tannic acid at molar ratios of 1:0, 1:100, 1:150, and 1:200, followed by encapsulation with 10% maltodextrin. This study evaluated the color stability and anthocyanins degradation of copigmented rambutan peel anthocyanins extract, along with its characteristics and stability in powder form during storage at low temperatures. The results showed that increasing Tannic acid from a molar ratio of 1:100 to 1:200 caused a 10 nm wavelength shift, and the absorbance increased from 3 to 15%. The 1:150 molar ratio resulted in the most significant improvement, effectively preserving red color stability and reducing anthocyanins degradation in copigmented anthocyanins. FT-IR analysis confirmed that the improved stability of the anthocyanins following tannic acid addition resulted from intermolecular interactions. Moreover, the incorporation of tannic acid produced anthocyanins powder with smoother surfaces and greater uniformity. The highest half-life values and the lowest ΔE values were observed for the anthocyanins powder stored at -16 ± 5 °C.

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This study evaluated the potential of unconventional starches extracted from Andean tubers, ulluco (Ullucus tuberosus) and cubio (Tropaeolum tuberosum), as raw materials for 3D food printing. Gels were formulated with starch concentrations of 8%, 10%, and 12% (w/v) and characterized in terms of microstructure and rheological properties. Both starches exhibited suitable printability, attributed to their pseudoplastic flow behavior. However, the hardness of the printed structures varied depending on starch type and concentration. Cubio starch showed higher hardness at both low and high concentrations (8% and 12%), whereas ulluco starch exhibited its highest hardness at the lowest concentration. Microscopic analysis revealed reticulated networks whose homogeneity was influenced by the degree of gelatinization and the starch content in the matrix. The printed gels demonstrated good resilience, variable hardness, and low crystallinity, indicating thermal-induced disruption of the native ordered structure. Rheologically, the samples showed viscoelastic behavior dominated by the elastic modulus (G’) and fitted the power-law model. These findings support the technological feasibility of ulluco and cubio starches as functional ingredients for the development of customized or functional foods through additive manufacturing technologies. Their application may foster the utilization of underused crops and contribute to the diversification of raw materials in the food industry.

Food spoilage is one crucial problem and is very challenging to determine with accuracy. Food safety, food quality, shelf life and consumer health are factors linked to food spoilage and this research work explores the possibilities of developing a smart biopolymer film capable of detecting food spoilage. The anthocyanin extracted from red cabbage (Brassica oleracea var. capitata f. rubra) was incorporated into the cellulose matrix extracted from Water hyacinth (Eichhornia crassipes (Mart.) Solms), creating a smart pH sensitive biopolymer film. A 41% cellulose yield (8.2 g from 20 g) was obtained from WH, and 654.54 mg/L anthocyanin was incorporated to form a pH-sensitive biopolymer film. The Cellulose red cabbage anthocyanin (CRA) film showed distinct color transitions dark reddish pink (pH 2), purple (pH 5), grey-blue (pH 9) and improved mechanical properties with tensile strength rising to 22.25 ± 0.79 MPa and Young’s modulus to 1380.34 ± 223.86 MPa. Studies on cellulose extracted such as yield of cellulose, moisture and ash content and FT-IR, HPLC analysis to identify the various functional groups of cellulose were performed. The developed biopolymer film exposed to fresh milk (pH 6.7, 0.19% acidity) displayed a purple colour shade, whereas milk stored for 24 h (pH 5.25, 1.8% acidity) showed a pink-purple colour shade indicating spoilage in milk. The developed smart biopolymer film can detect spoilage of food with change in pH of food associated with spoilage.

This study investigated the effect of natural antioxidants from mullein flowers (Verbascum thapsus L.) on the quality and oxidative stability of linseed oil (Linum usitatissimum L.). Ultrasonic-assisted maceration was optimized by evaluating the effects of extraction time, ultrasonic power, and flower concentration. The optimal conditions for maximising oil oxidative stability were identified as 3.31 min of ultrasound, 40 W power, and 8.56% (w/w) flower content. Under these conditions, the oxidative stability of the oil improved significantly, with an average protective factor of 1.74. Although slight increases in hydrolysis and oxidation were observed, the oils remained within acceptable quality and safety limits. Maceration also enhanced oils’ bioactive compounds content, increasing phenolic content from 68.82 to 92.57 to 368.65–419.02 mg GAE/100 g and flavonoids from 6.24 to 8.87 to 34.54–38.20 mg QT/100 g. Additionally, the macerated oils had higher antioxidant activity, chlorophyll, and carotenoid levels. While the maceration process led to a reduction in individual fatty acid groups, the loss was less pronounced than that caused by ultrasound treatment alone. Overall, ultrasonic maceration with mullein flowers effectively improved both the bioactive properties and oxidative stability of linseed oil.

Alternative sustainable and green protein modification technologies for the improvement of functional properties of plant proteins are gaining increasing attention. This study investigated the novel application of plasma-activated water (PAW) as a gentle and uniform protein processing technology to enhance the functional properties of Soybean Protein Isolate (SPI). SPI was hydrated in PAW solutions prepared at different plasma exposure times (0–30 min) and then freeze-dried. Evaluations included Fourier transform infrared (FTIR) spectroscopy, sulfhydryl content, particle size, gel electrophoresis, surface hydrophobicity, solubility, water holding capacity, contact angle, and emulsifying activity and stability. Key findings revealed that PAW treatment induced partial unfolding of SPI, enhanced α-helix structure while reducing β-sheet content, particularly in the PAW20 group. Sulfhydryl group oxidation led to disulfide bond formation, transiently exposing buried groups and decreasing total sulfhydryl content. Surface hydrophobicity and solubility peaked at PAW15 treatment, significantly enhancing SPI’s emulsifying properties. Prolonged treatment (> 15 min) caused protein aggregation, diminishing functionality. Optimal PAW15 treatment improves SPI’s structural flexibility and interfacial properties, offering a sustainable strategy for developing high-performance plant protein ingredients in food systems. These results highlight the potential of PAW as a novel and effective method to improve the functional properties of plant proteins.

Proteins have potential to form the next generation of delivery vehicles for functional food and nutraceutical applications. Improved water solubility, biocompatibility and non-toxicity make them an attractive prospect for a health-conscious society. Research unveils these biopolymers as efficient encapsulators of bioactive compounds for controlled release, however, much of the literature does not explore the microstructural properties and physical mechanisms governing release from such systems. Of particular interest is the role of the aqueous solvent in controlling small molecule diffusivity. At a low level of solids, the presence of solvent alters the physical landscape of the protein and defines critical parameters such as crosslink density, mesh size and intermolecular coupling constant as tuneable properties to control release. As the level of solids increases, the landscape again shifts. Here, protein molecules can be treated using the free volume theory to ascribe a link between the mechanical glass transition temperature and bioactive compound release. While the focus of this review is on proteins, the industrialist must also consider protein and polysaccharide mixtures, as they closely resemble industrial formulations. Here, we demonstrate how the use of fundamental rheology-based blending laws provides a mechanistic understanding of these composite gels in relation to bioactive compound diffusion.

Extrusion cooking is a popular high temperature short time pasteurization (HTST method) for preparing snacks and ready-to-eat food products. This study investigates the incorporation of underutilized medicinal plants ashwagandha, gudwel, ginger, and drumstick leaves into extruded snacks made from sorghum, corn, and millet. A single-screw extruder and response surface methodology (RSM) were used to evaluate the effects of six independent variables on product characteristics such as mass flow rate, bulk density, expansion ratio, water absorption index, texture, color, and sensory attributes. The impact of the independent variable on the dependent variable was shown using the second-order polynomial regression equation. The best-optimized product was prepared at 15% moisture content, 60:30:10 blend ratio, 5% ashwagandha, 9% ginger, 2% gudwel, and 2.5% drumstick leaves powder. The corresponding values for the optimized product were: 0.324 g/s mass flow rate, 0.214 g/s bulk density, 4.326 expansion ratio, 416.68% water absorption index, 627.135 hardness, 9.215 crispness, color L-value 62.447, and overall acceptability 7.870. The optimized extrusion process successfully enhanced the nutritional and sensory properties of medicinal plant-enriched snacks, demonstrating their potential for functional food applications.

The interactions between Agaricus bisporus lectin (ABL) and phenolic acids, 4-hydroxybenzoic acid (4HBA) and p-coumaric acid (p-CA), were found to be non-covalent in nature at neutral pH and ambient temperature according to UV-vis analysis. Secondary structure analysis of the ABL on complexation with 4HBA or p-CA showed a reduction in α-helix content of around 3 and 4%, respectively. Intrinsic fluorescence quenching indicates that the association constant between ABL and 4HBA is stronger (1.27 × 10⁵ M^− 1) than ABL and p-CA (1.88 × 10⁴ M^− 1), with molecular docking analysis also showing a stronger binding energy (ΔG) for ABL-4HBA (-20.1 kJ/mol) than ABL-p-CA (-16.3 kJ/mol). Docking also suggests that phenolic acid interactions occur in the glucose binding region of ABL, stabilized mainly by multiple hydrogen bonds, notably including Arg103, which is also suspected to be a significant residue in glucose binding. These findings provide valuable insights into the binding behaviour of ABL with naturally occurring phenolic compounds, contributing to a better understanding of its potential bioactive properties in functional foods or as a nutraceutical.

As a predominant etiological agent of dental caries, Streptococcus mutans plays a pivotal role in the development of dental plaque. Given that the fermentative bacteria from Pu’er tea exert inhibitory effects on Streptococcus mutans, in this study, we examined the co-aggregation interactions between nine strains of Pu’er tea fermentative bacteria and three strains of Streptococcus mutans. Notably, Bacillus camelliae 7578-1 ^T and Paenibacillus yunnanensis YN2^T demonstrated robust co-aggregation capabilities. Treatments with sugars, heat, proteases, and amino acids, revealed that protein and saccharide molecules on bacterial surfaces significantly contribute to intergeneric co-aggregation. Importantly, strains 7578-1 ^T and YN2^T reduced the biofilm biomass and culturable cell counts of Streptococcus mutans, indicating their potential for maintaining oral health. Furthermore, hydrophobic interactions, disulfide bonding, and hydrogen bonding were observed in dual-species biofilms. This research elucidates the functional significance of Pu’er tea fermentative bacteria in regulating oral microbial communities and lays a groundwork for further investigation into their potential utility in the prevention of dental caries.