Food research international (Ottawa, Ont.)最新文献

To explore the potential applications of pea protein isolate-pectin-pterostilbene complex (PPI-PEC-PT) in the sauce industry, its solubility, antioxidant capacity and oxidative stability were measured. The results indicated that PPI-PEC-PT exhibited a solubility of 77.67 %, more than double that of PPI-PT (31.93 %). The DPPH radical scavenging capacity of PPI-PEC-PT reached up to 78.52 % at a concentration of 50 μg/mL. After accelerated oxidation (60 °C, 7 days), the peroxide value (8.15 mmol/L) and malondialdehyde content (11.50 mmol/L) of PPI-PEC-PT emulsion were significantly lower than those of PPI. Additionally, when applied to walnut butter, PPI-PEC-PT significantly enhanced its gel properties. In conclusion, PPI-PEC-PT could not only serve as a natural antioxidant but also be utilized as a food additive to enhance the gelling properties of products in the food industry.

There is growing interest in developing protein-rich foods for the elderly using plant proteins. The application of soy protein isolate (SPI) as a model protein to create protein-rich, custard-like soft foods presents a unique opportunity for innovative formulations tailored to those within the aging population suffering from swallowing difficulties. This study investigated the physicochemical and textural properties of custard-type soft food formulations developed using SPI for dysphagic elderly individuals, with the goal of achieving characteristics similar to those of optimal milk protein-based counterparts. The protein content in the SPI-based custards varied from 8.9 % to 13.9 % and the milk-protein based custards had 8.9 % protein content. There was a substantial difference in textural, rheological and creep resistance and other properties between SPI and milk protein-based formulations. The SPI-based custards also had lower water-holding capacity, looser structure, and higher level of insoluble protein aggregates. The SPI-based custards imparted a more spreadable mouthfeel suitable for the aging population. The custards containing 13.9 % SPI had higher gel strength, viscosity, texture, and product stability. All of these custards were classified as Level 6 - Soft & Bite-sized dysphagia diet, based on International Dysphagia Diet Standardisation Initiative (IDDSI) tests. Instrumental IDDSI tests for Level 6 foods corroborated these observations, yielding reliable and consistent data. This research provides insights for developing protein-rich plant-based soft foods intended for the elderly population that have characteristics close to milk protein-based custards and comply with IDSSI criteria.

This research investigated the influence of the microencapsulation of phenolic compounds (PCs) from organic coffee husk with whey protein concentrate (WPC) and maltodextrin on the abundance of intestinal bacterial populations and their metabolic activity during in vitro fecal fermentation. The microencapsulated PCs were gradually metabolized during fecal fermentation, resulting in significant transformations and an increase in PCs in the fermentation media. The metabolism of PCs by the fecal microbiota occurred concurrently with the consumption of sugars, production of organic acids, and reduction in pH in the media. The PCs, especially when encapsulated, promoted an increase in the abundance of Lactobacillus spp./Enterococcus spp., Bifidobacterium spp., and Ruminococcus albus/R. flavefaciens, and a reduction in the abundance of Bacteroides spp./Prevotella spp., Clostridium histolyticum, and Eubacterium rectale/Clostridium cocoides. The results suggest that the PCs exhibited prebiotic potential, with their efficacy enhanced by microencapsulation, particularly when WPC was used exclusively as the encapsulating agent.

In this study, we assessed the effects of temperature and dilution on uropathogenic Escherichia coli (UPEC) growth in sugarcane juice and modeled the kinetics for shelf life simulation. Diluted and undiluted sugarcane juice samples inoculated with a four-strain UPEC cocktail were stored at 4, 10, 15, 20, 30, and 40 °C to evaluate their growth during storage. Changes in UPEC growth were fitted using three primary models (Baranyi, Huang, and reparameterized Gompertz models), and two secondary models (Huang square-root and Ratkowsky square-root models) were selected to evaluate the effect of temperature on specific growth rates. The best-fitted models (reparameterized Gompertz and Huang square-root models) were validated by an additional experiment under isothermal storage (35 °C). Combining differential forms of the Baranyi model, the prediction performances of these models were further validated under storage at dynamic temperature profiles (15 to 37 °C in 4-h cycles). Results revealed that UPEC growth was observed in diluted and undiluted juice samples at storage temperatures of 15 to 40 °C. No growth of UPEC was found in either type of juice at storage temperatures below 10 °C. The estimated minimum growth temperatures (T_min) of UPEC in sugarcane juice and diluted juice were 10.7 and 11.2 °C, respectively. Validation results showed that the model perfectly estimated UPEC growth under isothermal conditions in both types of sugarcane juice (proportion of prediction error (pPE) = 1.00). Predictions of dynamic conditions in sugarcane juice (pPE = 0.73) and diluted juice (pPE = 0.91) were acceptable, at pPE > 0.7. Using the model, shelf life charts were derived based on the time to reach a certain microbial concentration. In conclusion, these results together with shelf life charts provide valuable information for the food industry to enhance sugarcane juice safety.

Aroma plays a crucial role in the quality of pure green tea beverage. However, there are limited methods to improve their aroma. In this study, green tea produced using shaking and piling process (SPGT) demonstrated a notable improvement in aromatic intensity, particularly in floral, fruity, and sweet notes. A total of 58 volatile compounds were detected, with SPGT exhibiting the highest concentration of aroma compounds among the tested green teas. Eight key aroma compounds were selected based on a relative odor activity value (ROAV) greater than 1 in SPGT: dimethyl sulfide (71.14, cooked corn-like), 2-methylbutanal (3.17, cereal), octanal (1.31, fruity), linalool (5.25, floral), nonanal (5.00, floral), (E)-2-nonenal (2.81, cucumber), decanal (22.90, fruity), and β-ionone (60.51, floral). The concentration of aroma compounds, especially for floral and fruity key volatile compounds significantly increased during the shaking and piling process (p < 0.05), and their formation pathways help explained these changes. Our results provided a new theoretical foundation and practical guidelines for producing the high-aroma green tea.

Recently, interest in eco-friendly techniques for producing antibacterial food packaging films has surged. Within this context, plasma polymerization is emerging as a promising approach for applying degradable antibacterial coatings on various plastic films. This research therefore employs an atmospheric pressure aerosol-assisted plasma deposition technique to create polyethylene glycol (PEG)-like coatings embedding zinc oxide nanoparticles (ZnO NPs) of varying sizes on polyethylene (PE) substrates. The antimicrobial efficacy of these plasma-polymerized PEG-ZnO coatings against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) is assessed, demonstrating a robust antibacterial effect, particularly when using smaller ZnO NPs (35-45 nm). The deposition of uniform, conformal PEG-ZnO nanocomposites with a chemical composition akin to standard PEG polymers has been achieved. In addition, ZnO NPs are homogeneously dispersed within the PEG matrix, up to a concentration of 1 wt%. To assess the antibacterial performance in contact with real food, pasteurized pork sausages inoculated with a mixture of L. monocytogenes or LAB strains are wrapped in plasma-coated PE and vacuum-packed. Bacterial growth is monitored during storage at 7 °C over time, demonstrating that the developed plasma-polymerized PEG-ZnO nanocomposite effectively inhibits bacterial growth during refrigerated storage, with a more pronounced effect on LAB. The release of Zn from the developed PEG-ZnO nanocomposite into various food simulants also remains below the specific migration limit (5 mg kg^-1 or L^-1 food), confirming coating safety. Overall, plasma-polymerized PEG-ZnO nanocomposite coatings thus show great promise as effective degradable antimicrobial films for food packaging applications.

A soybean protein isolate (SPI)-based hydrogel with controllable properties was prepared under mild conditions using a simple mixing method with dialdehyde sodium alginate (DSA) as an eco-friendly macromolecular crosslinker. DSA was successfully synthesized via periodate oxidation. Analysis of the structure of the SPI/DSA hydrogel indicated that a 3D network was formed between SPI and DSA through dynamic imine and hydrogen bonds. The analysis of the physicochemical properties of the hydrogels showed that the micropore size, mechanical properties, and the swelling and release behavior of the hydrogels could be effectively regulated by changing the DSA content. When 3.0 wt% DSA was added, the hydrogel exhibited a dense and homogeneous network structure with optimal gel properties, which enabled the controlled release of curcumin. This effective structure is mainly attributed to the synergistic effect of short- and long-range chemical and physical crosslinking. Overall, the SPI/DSA hydrogels are effective carriers for the controlled release of bioactive compounds.

This study explored the effect of electrical stimulation (ES) and Pediococcus pentosaceus LL-07 (P. pentosaceus LL-07) and Staphylococcus simulans QB7 (S. simulans QB7) on the quality and microbial community of loin ham during the ripening. After the ES and starter culture treatments, the Aw and pH were decreased. Surface hydrophobicity, myogenic fiber fragmentation index (MFI), TCA-soluble peptide, amino nitrogen and free amino acids (FAAs) were also significantly higher than the control group (CK) (P < 0.05). This increase was more significant in the E-S group (electrical stimulation followed by inoculation with P. pentosaceus LL-07 and S. simulans QB7) than the rest of the experimental group (E、S、S-E group). Furthermore, the CK and E-S groups were subjected to a bacterial community comparison experiment. The microbial diversity of these two groups was increased. Pediococcus spp. and Staphylococcus spp. became the dominant bacteria in E-S groups during the ripening. Correlation analyses show a strong correlation between protein hydrolysis, microorganisms and FAAs. In conclusion, the combination of ES and starter culture could promote protein hydrolysis, the accumulation of FAAS, and improves the bacterial community of loin ham.

This study aimed to investigate the effect of the combination of shaking and various anaerobic treatments on the aroma quality of gabaron oolong tea (GAOT) by chemical and sensory evaluation. The results showed that elevated anaerobic treatment harmed GAOT aroma, emphasizing undesirable attributes such as earthy, fatty, etc. A total of 85 volatiles were identified by gas chromatography-ion mobility spectrometry (GC-IMS), and the relationship between aroma attributes and volatiles were revealed by PLS regression projection and correlation network. Hexanal and octanal at inappropriate concentrations were main causes to the earthy attribute, while nonanal exhibited a potential masking effect against unpleasant attributes. Addition experiments and σ-τ plot analysis verified these associations. Furthermore, observing dynamic patterns of content changes of these three aldehydes in fresh leaves prior to tea thermal processing, providing references for future process optimization. These results provide a new direction for enhancing the quality of GAOT.

The purpose of this study was to investigate the mechanism of enhancing gelling properties of low-salt surimi by utilizing the complementary advantages of L-arginine (L-Arg) and microwave (MW) from the perspective of gels' network characteristics. At MW 3 min, the diameters of protein filaments were increased from 0.015 μm to 0.06-0.08 μm by 2 % L-Arg. The gel strength was improved from 58.4 to 108.0 g × cm by 2 % L-Arg, the cooking loss was reduced (from 21.8 % to 3.8 %), and they showed a strong correlation (|r| ≥ 0.73) with the fractal dimension (D_f). These results suggested that the improvement (P < 0.05) of L-Arg in macro qualities was attributed to the denser microstructure. The intermolecular forces proved that L-Arg changed the dominant situation of hydrophobic interactions to a more balanced composition containing decreased hydrophobic interactions and increased ionic bonds, hydrogen bonds and disulfide bonds (P < 0.05) during the MW heating. The contribution of disulfide bonds was further proved by the reduced/non-reduced SDS-PAGE, and the increase of disulfide bonds can be explained by the conversion of sulfhydryl and the decreased proportion of α-helix. The present study can not only provide a universal theory for ameliorating the quality of low-salt surimi gels by regulating their microstructures but also promote the application of MW in surimi processing industry.