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关键词： Spices   Gamma radiation   Decontamination   Physico-chemical   Sensory characteristics  

摘要： The effect of gamma radiation on the decontamination of microbial population, physico-chemical, radiation sensitivity and sensory characteristics of common spices for storage were evaluated. Spices were irradiated with gamma doses of 0 (as control), 2, 4, 6, 8 and 10 kGy, packed in the glass vials and stored at room temperature (22 +/- 2 degrees C) in the laboratory. In this research, Bacillus, Salmonella and Listeria species were identified in un-irradiated spice samples. Results also indicated that gamma radiation reduced the total microbial population compared to control and optimum gamma radiation doses (6 kGy for red chili and turmeric;4 kGy for cumin, coriander, garlic and black pepper;2 kGy for ginger powder samples) were identified for decontamination of the organisms in the studied spices. It was concluded that no significant differences before and after gamma radiation were observed in physico-chemical, nutritional and sensory properties but significantly changed in microbial load in spices samples.

关键词： Plasma-activated water (PAW)   Cold atmospheric pressure plasma (CAPP)   Microbial inactivation   Storage stability   Reactive oxygen and nitrogen species (RONS)  

摘要： Plasma-activated water (PAW) is an emerging disinfectant with high antimicrobial activity due to a variety of reactive oxygen and nitrogen species. This study evaluated the inactivation efficacy of PAW against planktonic Escherichia coli and Listeria innocua as representatives of gram-negative and gram-positive bacteria, characterized the physicochemical properties of PAW, and investigated the storage stability of PAW. The effectiveness of PAW increased by extending the plasma activation time over water during PAW preparation or the incubation time of bacteria in PAW. PAW also showed higher effectiveness against E. coli than L. innocua: PAW5 (PAW prepared by plasma activation of water for 5 min) reduced E. coli by > 5 log CFU/mL and L. innocua by 1.8 +/- 0.5 log CFU/mL within 5 min of bacterial incubation time, while PAW15 (PAW prepared by plasma activation of water for 15 min) reduced E. coli by > 5 log CFU/mL and L. innocua by 3.5 +/- 0.6 log CFU/mL within 5 min of bacterial incubation time. Acidic pH and nitrogen species such as NO2-synergistically contributed to the inactivation efficacy of PAW. Fresh PAW showed the highest inactivation efficacy while refrigerated PAW maintained the inactivation efficacy compared to PAW stored at room temperature due to delayed dissipation of reactive species.

关键词： alumina-chromia catalyst   steam-air treatment   dehydrogenation   coke   Cr(VI)  

摘要： The effect that calcination of an alumina-chromia catalyst containing 13 wt % Cr with additions of Na+ and Zr4+ in an air-water vapor atmosphere (from 0 to 80 vol % water vapor) at 750 degrees C and a pressure of 1 bar exerts on the physicochemical properties of the catalyst and its activity in n-butane dehydrogenation was studied. The steam treatment leads to a slight decrease in the specific surface area (by up to 10%), partial decomposition of Cr(VI) compounds (up to 60%), and Cr2O3 crystallization. The catalytic activity decreases with an increase in the water vapor : air ratio. Low water vapor concentration (10 vol %) favors a significant decrease in the amount of the coke formed (by 60%) without significantly affecting the yield of alkenes. Thus, introduction of water vapor into the calcination atmosphere allows control of the Cr(VI) amount and catalyst selectivity.

关键词： Catechin   β   -cyclodextrin   Inclusion complex   Nanoparticles   Cooling precipitation  

摘要： Nano-size catechin/beta-cyclodextrin inclusion complex (CA/beta-CD IC) with 1:1 molar ratio was obtained by cooling precipitation at 4 degrees C. Physicochemical properties of the CA/beta-CD IC nanoparticles were characterized. Results of dynamic light scattering and SEM observation showed that CA/beta-CD IC molecules underwent a process of assembling and shaping nano-size particles. In the range of 10-14 mM, the higher the concentration of beta-CD aqueous solution, the faster the CA/beta-CD IC nanoparticles form and the larger the size of the nanoparticles (195.2-438.6 nm). The total recovery, inclusion ratio and loading capacity of the CA/beta-CD IC nanoparticles were determined. Results of FT-IR and DSC indicated that stability of CA was enhanced after it was embedded into beta-CD cavity. XRD results showed that the strongest three diffraction peaks (located at 2 theta = 10.6 degrees, 12.4 degrees and 19.6 degrees) of the CA/beta-CD IC nanoparticles was different from that (located at 2 theta = 6.6 degrees, 11.7 degrees and 17.7 degrees) of micro-size CA/beta-CD IC and the nanoparticles obtained from higher concentration solution possessed higher crystallinity.

关键词： Old wheat landraces   Malting quality   Wheat malt chemical composition   Wheat malt sugar profile   Local craft beer  

摘要： Craft beers produced by small breweries are becoming increasingly popular worldwide due to their unique composition, taste, and flavour. Wheat malt is a traditional brewing raw material with great potential to improve beer properties such as mouthfeel, foam, haze, and flavour. In this study, the malting quality of eight wheat varieties (four common and four durum) was evaluated to explore the feasibility of producing 100 % wheat malt beer from old landraces. The physicochemical characteristics such as friability, Kolbach index, viscosity, and colour, of the wheat malts indicated a better degree of modification in the common wheat varieties when compared to that of the durum wheat varieties. The wheat malts showed a proper enzymatic pattern, and significant differences in the enzyme activities were observed in durum and common wheat malts which affected the non-starch and starch polysaccharide content. The sugar content, profile, and extract levels of the congress worts were comparable to those of commercial malts. This study could be a useful resource that enables small brewing and malting to extend their product portfolio and promote the use of old landraces to produce beers with unique tastes and profiles.

关键词： Self-assembly   Supramolecular polymers  

摘要： Solution-cast films of ClO4--doped oligo(3-methoxythiophene) exhibit a luster similar to that of metallic gold;however, the effects of synthetic conditions on the physicochemical properties of the above oligomer and its films remain underexplored. To bridge this gap, this study examines how these properties are affected by (i) the time required to add the oxidant solution to the monomer solution (t(a)) and (ii) the polymerization time (t(p)) for oligomer synthesis, revealing that oligomer molecular weight, film conductivity, and the amount of edge-on lamellar crystallites increase with decreasing t(a) and/or increasing t(p). Given that the crystallinity of edge-on lamellar structures, together with film surface roughness, strongly influences film specular reflectance, the obtained results are expected to facilitate the fabrication of conductive oligo(3-methoxythiophene) films with tunable color and metal-like luster for diverse applications.

关键词： Lithology   Drainage   Physico-chemical parameters   K-40   Ra-226   Th-232   Central and northern Kerala  

摘要： The present study investigates the correlation between physico-chemical parameters and natural radionuclides, and relates its distribution with geographical factors of the study area. For the same, the activity concentration of natural radionuclides such as K-40, Ra-226, and Th-232 in sand samples collected from the central and northern parts of coastal Kerala, India has been measured using high efficiency NaI (Tl) detector and compared the concentration with 'favoring factors for distribution' that is lithology and drainage pattern. The activity concentration was also correlated with multiple phyisco-chemical parameters of the sand samples. The details of which are discussed in the manuscript.

关键词： functional properties   liquid whole egg   mineral supplement   physicochemical properties   salts  

摘要： The study aimed to evaluate the physicochemical and functional properties of liquid whole egg (LWE) with L-calcium lactate (L-Ca), zinc lactate (L-Zn), and sodium ferric EDTA (NaFeEDTA), and to compare with NaCl addition to determine the application potential of these mineral supplements. Results showed that salts addition significantly influenced the foaming, emulsifying, and gelling properties of LWE, which was possible through affecting the pH, particle size, surface hydrophobicity, apparent viscosity, and solubility. The addition of all the four salts reduced pH but increased the d(4,3) diameter of LWE. Additionally, the addition of 200 mM L-Ca and 6 mM L-Zn significantly improved the emulsifying capacity by 41.73% and 13.6%, the foaming capacity by 26.57% and 10%, and the protein solubility by 13.89% and 12.70%, respectively. In the meantime, mineral supplements tend to produce lower hardness gel, especially with 25 mM L-Ca and 8 mM L-Zn, and the hardness was decreased from 2401.13 to 1138.29 and 1175.59 g, respectively. A relative decrease in hardness was desirable in gelled egg products. Moreover, the addition of NaCl and L-Ca showed a higher redness and yellowness, but the addition of NaFeEDTA showed an undesirable color in dark brown, which may be not accepted by the public. In summary, L-Ca and L-Zn had great potential for application in LWE, which was more appropriate than adding NaCl. This study provides a basis for improving the functional properties of LWE products in the future. Practical Application The addition of L-Ca and L-Zn to liquid whole egg (LWE) could improve the foaming and emulsifying capacity of LWE as well as produce a lower hardness gel, which may be more conducive to the production of cake, custards, and meat products. Meantime, it is more in line with people's pursuit of a healthy diet.

关键词： Dry matter   Pasteurization   Infant formula mix   Flowability   Rehydration   Particle size  

摘要： This paper investigated the effects of heat treatment (75 degrees C x 18 s and 100 degrees C x 18 s) and wet-mix total solids level (TS: 50 and 60%, w/w) on the physicochemical and techno-functional properties of model infant milk formula (IMF) powders. IMF produced from wet-mixes with 50% TS preheated at 75 degrees C (50%-75 degrees C) exhibited the longest wettability time (55 +/- 2 s) and the poorest flowability, explained by the small particle size (D [4:3]= 16.5 +/- 2.29 mu m) and low poured bulk density (0.27 +/- 0.02 g/cm(3)). Larger particles were obtained by increasing both pasteurization temperature and TS. Further, powders from 60%TS wet-mixes showed less particle size uniformity, leading to better packing and higher bulk densities. 50%-75 degrees C powders also showed the lowest onset glass transition temperature, which may affect its storage stability. Wettability time was reduced by increasing TS from 50 to 60% or by increasing pre-heating temperature from 75 to 100 degrees C. However, as observed by low-field nuclear magnetic resonance, the increase in the pasteurization temperature slowed down the global rehydration process. The flowing properties of the powders improved by increasing TS level of the wet-mix. In conclusion, the pre-spray drying wet-mix processing variables, pasteurization temperature and TS level, had a major effect on the physicochemical and functional properties of the IMF powders. It is crucial to understand how variations in the process parameters affect these powder characteristics, due to their functional, technological and economic importance. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Transition metal   Co(II) diphosphate cluster   Optimized geometry   Magnetic properties   Molecular docking  

摘要： Interaction of the diphosphoric acid (H4P2O7) and organic ligand (3.4-dimethylaniline) with transition metal ions, cobalt (II) chloride leads to the formation of novel stable Co(II)-diphosphate cluster with empirical formula (C8H12N)(2)[Co(H2P2O7)(2)(H2O)(2)]center dot 2H(2)O. The structure of the synthesized material was confirmed by single crystal XRD at 120 K. The crystal was plate and crystallized in the triclinic P (1) over bar space group with a = 7.5340(4) angstrom, b = 7.5445(4) angstrom, c = 13.6896(8) angstrom, alpha = 84.215(5)degrees, beta = 76.038(5)degrees, gamma = 74.284(5)degrees, V = 726.38(7) angstrom(3) and Z = 1. Full-matrix least-squares refinement converged at R = 0.035 and Rw = 0.088 for 3636 independent observed reflections. Indeed, the purity phase was confirmed by the powder X-ray diffraction. A detailed analysis of the intermolecular close interactions and their percentage contribution has been performed based on the Hirshfeld surfaces and their associated two-dimensional fingerprint plots. In this context, spectroscopic studies were performed to distinguish the different chemical functional groups and their environments in this molecule. To determine the optical properties, the UV-Visible and luminescence behavior were investigated. The magnetic properties have been investigated in the temperature range 2-300 k. The geometry of the hybrid complex was optimized in the gas phase, using density functional theory (B3LYP) with the 6-31+G (d,p) basis sets, it is found that the calculated and the experimental results were in good consistency. Furthermore, the synthesized product was screened for its antioxidant activities. Molecular docking study was additionally carried.