查看更多>>摘要：The present work investigated the feasibility of reusing soy peptide aggregates (SPA) obtained from the hydrolysis of soy protein. Nanoparticles were prepared using SPA and epigallocatechin-3-gallate (EGCG) after ultrasound treatment as emulsion stabilizers. The particle size, particle wettability, and surface hydrophobicity of the nanoparticles were measured, and other properties were assessed with Fourier transform infrared spectroscopy, scanning electron microscopy, and antioxidant capacity analyses. EGCG-SPA complexes nanoparticles (ESPNs) were regular spherical particles of 87.52 nm at an EGCG concentration of 0.8% (0-2.0%). With increasing EGCG concentration surface hydrophobicity decreased and antioxidant capacity increased. The emulsion stability, droplet size, rheology behavior, and microstructure of emulsions stabilized via SPA, SPA nanoparticles (SPNs), and ESPNs were also characterized. The emulsions stabilized by ESPNs showed extraordinary stability, smaller droplet size, and higher viscosity and modulus. This work establishes the feasibility of ESPNs as an effective emulsifier for enhancing the value of SPA.
查看更多>>摘要：This study aimed to evaluate the impacts of cinnamon essential oil nanoemulsions (CON) on the microbiological, physicochemical, and sensory attributes of chicken breast fillets during refrigerated storage. The nanoemulsions containing 0.25%, 1.0%, and 2.0% (w/v) cinnamon essential oil were prepared and referred to as LCON, MCON, and HCON, respectively. The results showed that CON could effectively inhibit the microbial growth in chicken breast fillets during storage at 4 degrees C. On day 15, the total viable count of chicken breast fillets treated with CON decreased by 1.00-3.95 log10 CFU/g when compared to the untreated samples (8.50 log10 CFU/g). As compared with controls (8.78 log10 CFU/g), Pseudomonas deceptionensis CM2 cells in CON-treated chicken fillets reduced by approximately 1.42-3.30 log10 CFU/g, respectively, at day of 10. CON also effectively improved the quality attributes of refrigerated chicken fillets during 15 days, such as pH, color (CIE L*, a*, and b*), lipid oxidation, and total volatile basic nitrogen content. HCON-treated fillets presented the highest scores in overall acceptance of sensory properties during storage. In summary, CON can be used to ensure the microbiological safety and quality of chicken meat during the chilled condition.
查看更多>>摘要：Little is known about the relationship between the chemical and microbial properties of Chouguiyu, a traditional Chinese fermented fish with unique aroma and plentiful taste. Therefore, we explored this relationship by determining the bacterial and fungal distribution of 14 brands of Chouguiyu. The distribution of microorganism and their effect on product quality, such as volatile flavor compounds (VFCs), free amino acids (FAA), physicochemical features and organoleptic properties were evaluated. Five VFCs (2-ethyl-1-hexanol, eucalyptol, 1octen-3-ol, nonanal and indole) and three FAAs (Glu, Vla and Ala) were considered as core components. LAB (Vagococcus and Lactococcus) were found to contribute greatly to critical aroma formation and inhibition of TVBN, leading to a moderate fermentation and good quality. While excessive increases in TVB-N, VFCs and FAA contents were found to be related with Psychrilyobacter and Fusobacterium, leading to poor organoleptic properties. The addition of Sufu to these products may be associated with the accelerating the fermentation process. Moderate fermentation with LAB is beneficial to typical aroma and good organoleptic properties, while excessive fermentation related with Psychrilyobacter and Fusobacterium may lead to overpowering flavors and lowered organoleptic properties.
查看更多>>摘要：In the present study, label-free quantification was used to study the protein changes in camel milk during homogenization. In the control and homogenization groups, we quantified 280 and 264 proteins, respectively between two groups. For the homogenization group, camel milk protein particles were smaller and more evenly distributed, and the ratio of each secondary structure of camel milk proteins changed compared with those in the control group. Proteomic analysis verified higher levels of FABP domain-containing protein, lactoperoxidase isoform 1 preproprotein, and lactoferrin in the control group than in the homogenization. For Kappa-casein, peptidoglycan-recognition protein, and Alpha-1-acid glycoprotein, the opposite result was observed. These proteins are associated with biological processes such as single organism process and cellular process. In the homogenized camel milk, significant changes were found in the proteome related to glycolysis/gluconeogenesis metabolism. The findings of the present study provide detailed information regarding the proteomic characteristics of homogenized camel milk.
查看更多>>摘要：This study aimed to develop a simultaneous drying and disinfection method for off-ground harvested almonds to improve drying efficiency and product safety. Almonds were dried in a column dryer (0.57 m-height) with hot air under constant temperature (ambient, 40, 50 and 60 degrees C) or step-down temperature (preheating with 80 degrees C and 90 degrees C, holding for 1-3 h, then stepping down to complete drying at 60 degrees C) and 1.0 m/s velocity. The drying time ranged from 240 to 2160 min to dry almonds from initial moisture content of 0.41 kg water/kg wet mass to a targeted 0.12 kg water/kg wet mass. Specific energy consumption ranged from 14.3 to 22.0 MJ/kg. No cavity, significant color change, concealed damage or oil quality deterioration were observed under all tested conditions. Step-down temperature drying with holding achieved up to 0.8 log CFU/g total bacterial counts reduction of in-shell almonds. Drying in-shell almonds saved up to 75% drying time and 78.6% specific energy consumption compared to drying in-hull almonds under the same temperature, with more uniform final moisture distribution. The findings suggested off-ground harvested almonds should be sorted and de-hulled prior to drying, which could significantly improve the drying efficiency, moisture uniformity and throughput of the drying process.
查看更多>>摘要：A total of 25 traditionally procured white cheese were collected from the Samsun region in Turkey. Selected physicochemical and microbiological characteristics of the cheese were screened via classical analysis and significant differences were detected between cheese samples. In this study, twelve lactic acid bacterial isolates with high antimicrobial activity from these cheeses were selected for further analysis. Isolated strains were identified and characterized by phenotypic and genotypic methods, and their probiotic and industrial properties were studied. Nine of the isolates were identified as enterococci (4 E. durans, 3 E. faecium, 1 E. faecalis and 1 E. gallinarum). Other identified strains included 2 Lactiplantibacillus pentosus, and 1 Loigolactobacillus coryniformis subsp. torquens. A series of established in vitro tests were conducted to determine the probiotic potential of isolates. These tests include bile and gastric juice tolerance, antibiotic resistance, ability to survive at different temperatures, pH ranges, and salt concentrations, acid-producing ability, proteolytic activity, beta-galactosidase production, and the ability to produce gas from glucose. The results of the study suggested that the E. faecium S1113, E. durans S104, E. durans S1121, and E. durans S202 isolates have potential use as novel probiotic strains in the food industry.
查看更多>>摘要：Using ionotropic gelation technique, Citrus medica L. phenolics was encapsulated in Ca-alginate microbeads to deliver associated health benefits. Microbeads were strengthened by polysaccharide fillers (starch, carrageenan, and pectin) at different concentrations (0.5-4 g/100 mL) for an effective phenolic encapsulation, controlled release, and swelling. All blended solutions were subjected to a similar set of instrumental conditions for controlled extrusion. Whereas, three polymeric combinations (ASE, ACE, and APE) with higher encapsulation efficiencies (EE%) were selected. Furthermore, the impact of polysaccharide fillers on physical properties of Caalginate microbeads, such as size, sphericity factor, viscosity, and water activity, was investigated. In contrast to AE, ASE, and ACE microbeads, APE (pectin; 2 g/100 mL) showed highest EE% (90.18) and antioxidant activity with a half maximal effective concentration (EC50) of 108.97 mu g/mL. Under in vitro gastrointestinal conditions, APE outperformed in terms of controlled release and swelling. While, UHPLC-DAD-QTOF-IMS also showed the higher amount of hesperidin (264.11 mg/100 g) and polymethoxy-flavones (PMFs) encapsulated in APE microbeads. The chemical interaction was confirmed by FTIR, which showed similar C-H stretching of aromatic components in APE and CMEE. Overall, the study revealed that Ca-alginate microbeads with polysaccharide fillers improved entrapment and controlled delivery of citrus phenolics for therapeutic uses.
查看更多>>摘要：Patulin (PAT) and alternariol (AOH) are the main mycotoxin contaminants in fruits and their products, which have great toxic effects on human body due to their teratogenicity and carcinogenicity. This study proposed a surface enhanced Raman spectroscopy (SERS) technology combining chemometrics and coffee-ring effect to build high-throughput label-free detection models for PAT and AOH. A stable coffee ring structure was built by optimizing the drying temperature and droplet volume. Comparing the partial least squares (PLS) models grounded on variables selection method, the best performance was obtained by using synergy interval (Si) and genetic algorithm (GA) for PAT (R-c = 0.9905, R-p = 0.9759) and AOH (R-c = 0.9829, R-p = 0.9808), respectively. The limits of detection (LOD) for PAT and AOH were as low as 1 mu g L-1, and the recovery rates were 92.80%-114.83% with relative standard deviation (RSD) = 4.86 for PAT and 82.06%-108.13% with RSD <= 2.28% for AOH. The SERS technology combined with chemometrics and coffee-ring effect holds promise for high-throughput label-free detection of PAT and AOH in fruits and their products.
查看更多>>摘要：Enhancing aminopeptidase fermentation using cheap substrate is very necessary for industrial production and application of aminopeptidase. The suitability of using raw soybean meal (SBM) as substrate for aminopeptidase production by Bacillus licheniformis SWJS33 in submerged fermentation was first evaluated. SBM alone provided both nitrogen and carbon sources for SWJS33 to produce aminopeptidase. Supplementation of 3 g/L glucose and 15 g/L yeast extract further improved the aminopeptidase yield by 0.63 and 1.3 folds, respectively. Addition of yeast extract altered the metabolic process of SWJS33, including shortening the lag phase, increasing the maximum specific cell growth rate and maximum specific aminopeptidase formation rate, and changing the utilization process of nutrients during the fermentation. What's more, SWJS33 secreted aminopeptidase prior to endoproteases when quick-release nitrogen (e.g. yeast extract) was supplied. High dissolved oxygen was demanded during aminopeptidase fermentation. The aminopeptidase production was successfully up scaled to 20 L fermenter.
查看更多>>摘要：The present study prepared an innovative structured fruit (SF) product based on king oyster mushroom (Pleurotus eryngii), litchi juice and gellan gel, and evaluated its textural, nutritional and sensorial properties. The lyophilized mushroom semi-ball sample was immersed in litchi juice containing different concentrations of gellan gel (0.25% and 0.5%), the SF products were obtained after the gelation of gellan gel. The nutritional analysis showed that the SF product possessed higher fiber and protein content, while lower sugar content than fresh litchi fruit. It retained about 30%-50% ascorbic acid, total phenols and total antioxidant capacity of fresh litchi due to the heating process during gel formation. Texture profile analysis revealed that gellan gum improved the texture properties of the structured fruit on hardness, cohesiveness, gumminess, chewiness, and resilience. Sensory descriptive analysis found that most sensorial attributes were highly remained in the final product, but the juiciness was significantly decreased by the addition of gellan gum. Scanning electron microscopy (SEM) observation revealed the synergistic effects between the mushroom and gellan gel resulted in the improved structure properties. In conclusion, the SF product could be a good solution for improving nutritional intake and reducing fruit wastage.
NSTL
Elsevier