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关键词： Dietary fibre   Neutral side chains   Essential amino acids   gamma-aminobutyric acid   Food composition  

摘要： This study reports physical parameters, proximate compositions, reducing sugar and amino acid contents in Amber, Laird's Large and Mulligan tamarillos that were produced in New Zealand. Across all three cultivars, about 3 % of dietary fibre was present. Higher amounts of neutral side chains were observed in pectin from Laird's Large compared to other cultivars and in pectin from pulps compared to peels. Among 22 detected amino acids, 2 essential amino acids and 5 non-essential amino acids were reported herein for the first time. The total amino acids content in peel and pulp of tamarillos ranged from 1192 to 1753 and 3455-6077 mg 100 g(-1) dry weight, respectively. L-glutamic acid, gamma-aminobutyric acid and L-aspartic acid dominated amino acid profile of Camarillo except for Amber peel. L-histidine and L-lysine dominated the essential amino acid profile of all tamarillo samples. Principal component analysis revealed a clear separation among soluble sugar and amino acid profiles of different cultivars and tissues of tamarillo.

关键词： Thyme essential oil microcapsules   Starch film   Antioxidant activity   Fruit preservation  

摘要： Essential oils are natural antibacterial substances with potential applications in packaging;however, due to their volatile and oxidizable properties, these materials have a low utilization rate. In this study, starch films containing thyme essential oil microcapsules (TEO-M) were prepared using the casting method, and the effect of the films on the quality and physicochemical properties of mango was evaluated. Scanning electron microscopy (SEM) image analysis showed that the structure of microcapsules presented higher integrity in starch films. The TEO-M starch film thermal stability was decreased compared to the stability of starch film alone. Fourier transform infrared (FT-IR) spectroscopy analysis revealed that TEO-M interacted effectively with starch films via hydrogen bonding. Furthermore, the TEO-M starch films showed an inhibitory effect against Botryodiplodia theobromae Pat and Colletotrichum gloeosporioides Penz. The addition of TEO-M to starch films increased the opacity, thickness, tensile strength and water solubility. Additionally, the TEO-M starch films presented lower elongation, moisture content and water vapor permeability. TEO-M starch films showed a better preservation effect compared with that of starch film alone. The shelf-life of mangoes treated with TEO-M starch films was 10 days at 25 degrees C. These results demonstrate the potential of developing TEO-M starch films for mango preservation.

关键词： Survey   Disease incidence   Sclerotinia sclerotiorum   Morphology   Soil texture   Ca   pH   Country bean   Correlation  

摘要： A survey was conducted to document the incidence of white mold disease in country bean production areas at Bogra, Pabna, Jessore, Sylhet, Hobigonj and Gazipur districts in Bangladesh during 2016-17. A total of 115 farmers' fields was surveyed from early vegetative to end of harvesting stages. Pathogens were collected from diseased stems, racemes and pods. Soil samples were collected from the same fields. White mold disease was identified based on symptoms in the field. White mold disease infection was recorded in 100% of the surveyed fields in Shahjahanpur upazila of Bogra district, while approx. 90, 80, 60 and 20% of the fields were infected in Bahubal of Hobigonj;Golapganj of Sylhet;Ishordi of Pabna and Monirampur of Jessore, respectively. White mold was not found in any of the fields surveyed in Joydebpur, Gazipur. Disease incidence and severity were higher in Shahjahanpur of Bogra and Bahubal of Hobigonj district. Moderate disease incidence and severity were observed in Golapganj of Sylhet. Pathogen infection was higher in the fields with loamy fine sandy soil with pH of 5.11-6.22. Globose to irregular black sclerotia developed in infected plant parts and the sclerotia germinated and produced apothecia in the fields after rain. Hyaline, branched, well developed and septate mycelia developed on potato dextrose agar medium. The hyphae were 2.0-7.2 mu m in width. After five days of incubation, the subsurface mycelial cells swelled and formed dark black sclerotia. The sclerotia were 1.5-6 mm in width and 2-17 mm in length. Sclerotia germinated, and brown colored round to globose shaped apothecia developed at the end of a long stipe. The length and diameter of apothecia were approximately 4-21 mm and 2-8 mm, respectively. Asci were hyaline and cylindrical in shape, while the ascospores were elliptical. The size of ascus and ascospore was 68-155 x 4.5-6.01 mu m and 4.7-6.94 x 4-6.2 mu m, respectively. Calcium oxalate was formed on the wall surface of the asci. Disease

关键词： multicomponent reacting mixtures   fuel combustion products   bulk condensation   submicron particles   numerical simulation  

摘要： A software package consisting of the TETRAN-PRO and the COND-KINET-1 proprietary computer codes, as well as computational methods and models they are based on, is described. The TETRAN-PRO code calculates the composition and thermodynamic properties of a multicomponent reacting system under thermodynamic equilibrium conditions, including products of combustion or pyrolysis of organic and composite fuels. The difference of this code from similar ones is the use of the method of prevailing components, which is most effective as to convergence, computation time, and the range of parameters used. The code includes the necessary database of the original thermodynamic properties for 3000 individual substances. The TETRAN-PRO code's capabilities are demonstrated by the results from calculation of mercury vapors' conversion in the combustion products of Kuznetsk and Berezovo coals. The COND-KINET-1 calculates the parameters of a condensation aerosol formed during the bulk condensation in a vapor-gas mixture flow. The process is described with a system of moment equations for the droplet size distribution function, which is closed by the equations of momentum and energy. A comprehensive approach, thermodynamic and kinetic, has been formulated to the description of the bulk condensation in multicomponent reacting systems based on the TETRAN-PRO and COND-KINET-1 codes. The approach's capabilities are demonstrated by the example of numerically simulating the formation of environmentally dangerous submicron particles in burning coals according to the condensation mechanism. Data on the concentration and size distribution of the generated particles are obtained. The predicted data on the fractional composition of particles are compared with the experiment.

关键词： aerosol   dispersion   exposure   nanoparticle   size distribution   suspension  

摘要： Physicochemical properties between colloidal engineered nanomaterials (ENMs) and aerosols released from consumer spray products were characterized. A dynamic light scattering (DLS), transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometer (ICP-MS) were used to evaluate the suspended ENMs in the products. Direct-reading instruments, TEM, and ICP-MS were used to characterize the properties of aerosolized ENMs. The aerosolized organic compounds with ENMs were assumed to be vaporized for a short time after spraying. The median diameter of ENMs in product solutions measured by DLS was about 200-350 nm, while individual particle was confirmed from 3 to 50 nm by TEM. The size of aerosolized ENMs was ranged from 7 to 44 nm, and their aggregates were about 100-1000 nm in near distance. Some inorganic substances including raw nanomaterials were also found in the aerosol. The particles released from the propellant sprays were identified in far distance, while they were not found in far distance when pump sprays were used. The number concentration from the propellant sprays increased up to 6000 particles/cm(3)/g at near distance and dispersed to far distance, while the most of droplets emitted from pump sprays were settled down near sprayer's location. We found other metals besides labeled ENMs are included in each product and the characteristics of the particles are different when they are sprayed.

关键词： Escherichia coli  

摘要： Leptospirosis is an emerging zoonotic disease in the Caribbean region and the island of Puerto Rico. Information on the presence of pathogenic Leptospira in rivers and streams of Puerto Rico is currently lacking. This study aimed to evaluate seasonal shifts in the presence of pathogenic leptospires and the level of Escherichia coli from 32 coastal locations in Puerto Rico's dry and wet seasons. Physicochemical parameters (temperature, salinity, pH, and dissolved oxygen) were determined at each site. The temperature (25.8 degrees C) and pH (average 7.6) values were all within acceptable USEPA regulatory standards. Thirty-eight percent of the sites of the dry season and 28% of the wet season sites contained dissolved oxygen levels <= 4 mg L-1, which is relatively low. In the dry season, 19 sites (59%) and 18 (56%) of the wet season sites had E. coli counts >410 most probable number (MPN) 100 ml(-1) and would be considered unsafe for recreational use. The lipl32 gene quantitative polymerase chain reaction assay was used for the detection of pathogenic leptospires in the samples. Low concentrations of pathogenic leptospires (<60 genome copies 100 ml(-1)) at Camuy, Espiritu Santo, Rio Guayanilla, Quebrada Majagual, and Rio Fajardo were detected during the wet season. Pathogenic leptospires were detected (similar to 40 genome copies 100 ml(-1)) at only one site, Loiza, during the dry season. There was no predictable relationship between the physicochemical parameters, concentrations of E. coli, and the presence of pathogenic leptospires in water samples.

关键词： Soursop pulp   Listeria monocytogenes   thermal treatment   inactivation kinetics  

摘要： Soursop (Annona muricata L.) is a commercially important tropical fruit, whether fresh or processed as a pasteurized or frozen pulp used to prepare juice, drinks, nectar, ice cream, popsicles, and desserts. Besides preserving quality, another preoccupation in the processing of fruit pulps is product safety. Several studies show the association between pulp processing and the development of various microorganisms;however, few have focused on the association between L. monocytogenes and the pulp of sour fruits. The objective was to evaluate the effect of moderate thermal treatments on the inactivation of L. monocytogenes and the physicochemical properties in soursop pulp in order to determine the best processing conditions that will allow to maintain quality as well as to achieve an adequate level of safety. Thermal inactivation kinetics were obtained for L. monocytogenes inoculated in soursop pulp at five levels of temperature (50, 52.5, 55, 57.5, and 60 celcius) and different exposure times (0-60 min). The survival curves did not suggest a log-linear relationship, and were, consequently, fitted to the modified Gompertz equation. The results indicated that the modified Gompertz equation provided an acceptable goodness of fit. Five-log(10) cycles reductions of L. monocytogenes were achieved at 50 celcius/60 min, 52.5 celcius/16 min, 55 celcius/10 min, 57.5 celcius/5 min, and 60 celcius/1.25 min. These 5-log(10) treatments applied to the soursop pulp indicated that the soursop pulp showed changes in the color parameters and a decrease in the content of total sugars, reducing sugars, ascorbic acid, total phenols, and pH.

关键词： Konjac glucomannan   Wheat gluten   Physicochemical property   Structural properties  

摘要： Konjac glucomannan (KGM), a dietary fiber, can be used to improve the quality of flour products. In this study, the effects of KGM at different concentrations on the water distribution, morphological, textural, thermal, and structural properties of wheat gluten were studied. KGM improved the physicochemical and structural properties of wheat gluten by changing the water holding capacity, secondary structure, and free sulfhydryl and disulfide bond contents. Scanning electron microscopy confirmed that KGM can evenly fill the network structure, affecting gluten network development. KGM exhibited no effect on moisture content;however, KGM decreased water mobility in wheat gluten. The increased thermal denaturation temperature indicates that KGM can improve the thermal stability of wheat gluten. Sharp changes in texture profile analysis (TPA) parameters were observed around 5% KGM, and elasticity and cohesiveness were optimal after the addition of 4% KGM. In addition, the secondary structure analysis indicated that a-helix and (3-sheet structures increased. The addition of 5% KGM increased the content of disulfide bonds by 2.57-fold. Overall, the changes in gluten structure and properties suggest that wheat gluten could be improved the stability, functionality and water holding capacity of gluten by adding KGM.

关键词： Beverages   Fermentation   Microbial quality   Physicochemical properties   Proximate composition  

摘要： Various fermented beverages have been produced and consumed across the world. Many of the low alcoholic traditional fermented beverages are valued for their nutritional values, safety and means of livelihood. The objective of this study was to assess microbial quality, physicochemical properties, and proximate composition of selected Ethiopian traditional fermented beverages.. The microbial analysis was conducted by homogenizing 25 ml of each sample in 225 ml sterile peptone water followed serial dilution, plating on respective culture media, incubation, and enumeration. Physicochemical and proximate analyses were done following standard analytical methods. Lactic acid bacteria (6.09-8.13 log CFU ml(-1)) and yeast (6.13-8.43 log CFU ml(-1)) dominated microbiology of all the three beverages, with highly significant (P = 0.000) differences in mean microbial count among samples. Physico-chemically, tej had more alcohol contents (8.23 +/- 2.07) than grawa (4.8 +/- 0.54) and borde (3.35 +/- 0.64). Likewise, content (g/100 ml) of carbohydrate (6.88 +/- 1.74), protein (3.20 +/- 0.39) and ash (0.78 +/- 0.12) of borde were significantly higher (P = 0.000) than that of grawa and tej. In general, borde had relatively higher microbial load and better nutritional quality. Thus, having improved the microbiological quality and designed mechanism for extension of the product's shelf life, borde could be used as nutritious local beverages.

关键词： corrosivity map   Fourier-transform infrared spectroscopy   mild steel   scanning electron microscopy   X-ray diffraction  

摘要： This paper has reported physicochemical features of mild steel's corrosion products and provided atmospheric corrosivity maps of Karachi harbor city, drafted on the basis of spatial distribution of corrosion data from July 2018 to June 2019 at 10 different urban, industrial, and marine test sites. Exposure tests have been performed to study atmospheric corrosivity, corrosion products, and corrodants including chloride, sulfur dioxide, time of wetness (TOW), and corrosion rate as per ISO and ASTM standards. Scanning electron microscope, Fourier-transform infrared spectroscopy, and X-ray diffraction have corroborated the presence of lepidocrocite, goethite, magnetite, and quartz phases at almost all the test sites, with slight variations in their morphologies and quantities. The data analysis has revealed that TOW is a major detrimental factor to accelerate corrosion of mild steel at Karachi city. The corrosivity category of all urban and marine test sites is found in C-4-C-5 range, whereas for industrial test sites, it is found in C-3-C-5 range. Resultant corrosivity maps have shown that the prevailing atmosphere is significantly corrosive at Karachi harbor city. This study has furnished a novel product of atmospheric corrosivity map, which is the first-ever corrosivity map for Pakistan.