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Widespread saline soils in Northwest China pose a serious threat to the region's ability to use infrastructure safely because they are prone to soil structure damage when subjected to external environmental fluctuations, which in turn affects the stability of the foundations for buildings. The non-destructive approach of measuring resistivity can be used to swiftly reflect the subsoil body's state and make assumptions about its safety. However, the electrical resistivity of the underground soil body can be used to quickly identify unstable areas because the resistivity is influenced by the water content, salt content, and structural characteristics of the soil body. To do this, it is necessary to understand the coupling relationship between various factors. In this study, we first constructed samples with various water, salt, and soil structure characteristics, and then used indoor tests, such as soil resistivity measurement and thermogravimetric analysis, to analyze the multiple factors affecting the resistivity characteristics of the soil. The relationship between soil resistivity and actual saline soil diseases in Northwest China was then further discussed in conjunction with the results of the indoor tests and analyses. subsequently, the resistivity and soil properties have been measured in the field at specific locations in Northwest China where railway roadbeds are diseased. The study's findings can theoretically support a deeper comprehension of the law and mechanism of soil resistivity change, as well as provide assistance for building infrastructure in Northwest China.
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Cloreto de Sódio , Solo , Solo/química , China , Água , EletricidadeRESUMO
Rapid and large-scale estimation of soil salt content (SSC) and organic matter (SOM) using multi-source remote sensing is of great significance for the real-time monitoring of arable land quality. In this study, we simultaneously predicted SSC and SOM on arable land in the Yellow River Delta (YRD), based on ground measurement data, unmanned aerial vehicle (UAV) hyperspectral imagery, and Landsat-8 multispectral imagery. The reflectance averaging method was used to resample UAV hyperspectra to simulate the Landsat-8 OLI data (referred to as fitted multispectra). Correlation analyses and the multiple regression method were used to construct SSC and SOM hyperspectral/fitted multispectral estimation models. Then, the best SSC and SOM fitted multispectral estimation models based on UAV images were applied to a reflectance-corrected Landsat-8 image, and SSC and SOM distributions were obtained for the YRD. The estimation results revealed that moderately salinized arable land accounted for the largest proportion of area in the YRD (48.44%), with the SOM of most arable land (60.31%) at medium or lower levels. A significant negative spatial correlation was detected between SSC and SOM in most regions. This study integrates the advantages of UAV hyperspectral and satellite multispectral data, thereby realizing rapid and accurate estimation of SSC and SOM for a large-scale area, which is of great significance for the targeted improvement of arable land in the YRD.
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In this study, the relationship between the physicochemical and microbiological properties of the Surk cheese was investigated through the analysis of dry matter (D.M.), ash, protein, salt, acidity, pH and enumeration of the total mesophyll aerobic bacteria (TMAB), yeast-mold, presumptive lactobacilli and lactococci. Surk samples were obtained randomly from 36 different local dairy shops in Antakya province of Turkey. The average values of the dry matter, ash, protein, fat, and salt, acidity and pH analysis were 44.4%, 9.09%, 17.5%, 17.0%, 8.08%, 0.916% and 4.17, respectively. The average values for TMAB, yeast mold, presumptive lactobacilli and lactococci enumeration in the microbiological analysis were found to be 6.23, 4.09, 6.04, and 3.42 log cfu/g, respectively. Based on the statistical analysis, Surk samples were divided into 3 groups in terms of salt content (3-6, 6-9 and > 9%). Then, the physicochemical and microbiological properties of Surk samples were evaluated according to these groups. This study suggests that besides the different methods to produce Surk cheese as followed by the different manufacturers, the amount of salt added to Surk cheese affects its microbiological and physicochemical characteristics.
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Organic hazardous waste often contains some salt, owing to the widespread use of alkali salts during industrial manufacturing processes. These salts cause complications during the treatment of this type of waste. Molten salt oxidation is a flameless, robust thermal process, with inherent capability of destroying the organic constituents of wastes, while retaining the inorganic ingredients in the molten salt. In the present study, molten salt oxidation is employed for treating a typical organic hazardous waste with a high content of alkali salts. The hazardous waste derives from the production of thiotriazinone. Molten salt oxidation experiments have been conducted using a lab-scale molten salt oxidation reactor, and the emissions of CO, NO, SO2, HCl and dioxins are studied. Impacts are investigated from the composition of the molten salts, the types of feeding tube, the temperature of molten carbonates and the air factor. Results show that the waste can be oxidised effectively in a molten salt bath. Temperature of molten carbonates plays the most important role. With the temperature rising from 600 °C to 750 °C, the oxidation efficiency increases from 91.1% to 98.3%. Compared with the temperature, air factor has but a minor effect, as well as the composition of the molten salts and the type of feeding tube. The molten carbonates retain chlorine with an efficiency higher than 99.9% and the emissions of dioxins are below 8 pg TEQ g-1 sample. The present study shows that molten salt oxidation is a promising alternative for the disposal of organic hazardous wastes containing a high salt content.
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Resíduos Perigosos , Oxirredução , Carbonatos , Dioxinas/química , Sais , TemperaturaRESUMO
This study describes the diffusion of NaCl and water in Gouda cheese during brining and ripening. Furthermore, we established water activity as a function of the NaCl-in-moisture content in Gouda cheese during ripening. We determined NaCl content, water content, and water activity in block-type Gouda cheeses that were brined for 3.8d and foil-ripened for a period of 26 wk, and in wheel-type Gouda cheeses that were brined for 0.33, 2.1, or 8.9d and subsequently nature-ripened for a period of 26 wk. The calculated diffusion coefficients of NaCl during brining were 3.6·10(-10) m(2)s(-1) in the block-type Gouda cheeses and 3.5·10(-10) m(2)s(-1) in the wheel-type Gouda cheeses. Immediately after brining, gradients of NaCl and water were observed throughout both types of cheese. During ripening, these gradients disappeared, except for the water gradient in nature-ripened cheeses. An empirical model was derived for Gouda cheese, in which water activity is expressed as a function of the NaCl-in-moisture content, as established for different brining times, locations and ripening times. Moreover, the effect of reduced water activity on inhibition of growth of Listeria monocytogenes in Gouda cheese was calculated. In addition to the presence of lactate and a pH of 5.2 to 5.3, the reduced water activity as seen in Gouda cheese can substantially contribute to inhibition of microbial growth and even to inactivation when cheeses are brined and ripened for extended times and subjected to nature-ripening.
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Queijo/análise , Manipulação de Alimentos/métodos , Listeria monocytogenes/crescimento & desenvolvimento , Cloreto de Sódio/metabolismo , Água/metabolismo , Queijo/microbiologia , Listeria monocytogenes/efeitos dos fármacosRESUMO
Salt content variability of dry-cured ham production is a challenge for the industry since many factors can influence salt uptake during the salting procedure. The aim of this work was to define and evaluate different modifications of the salting procedure to reduce the salt content variability of an industrial dry-cured ham production. Results showed that magnetic induction (MI) is a valid technology for industrial purposes as it can predict in-line the fat and salt contents of hams with a percentage error of 1.75% and 0.38%, respectively. Modifications of the salting process defined according to raw material characteristics obtained in-line reduced the salt content variability (SD) of the global production from 0.337% to 0.283%. Moreover, a 25% reduction of the salt content variability in hams of similar weight and fat content could be achieved when using a reclassification of the defined categories with MI technology after 6 days of salting. Because of the complexity of the salting process, new tools combined with strategies need to be investigated and developed to overcome the variability coming from other sources than weight and the fat content of hams.
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Manipulação de Alimentos , Produtos da Carne , Cloreto de Sódio na Dieta , Animais , Produtos da Carne/análise , Manipulação de Alimentos/métodos , Cloreto de Sódio na Dieta/análise , SuínosRESUMO
Several studies have been conducted in many countries on how to increase the per capita consumption of poultry meat. With the growing demand for poultry meat, the development of value added product, such as chicken nuggets has been identified as the best way to increase poultry meat consumption. Apart from this allowing for the flourishing growth of fast food industries; chicken nuggets needs to be produced in higher quantity and to reduce cost, there is increasing interest in using of various meat additives. Though, chicken fat are edible, it is important to evolve production processes for gainful utilization of this part. So the main objective of this work was to study the effect of the addition of chicken fat and various salt contents on the physicochemical, proximate composition and sensory characteristics of chicken nuggets. Based on the results it is concluded that, even up to 5% level of chicken fat with 1.5-2% added salt there is no adverse effect in terms of physico-chemical, proximate composition and sensory qualities of cooked chicken nuggets. Even, at this fat and salt level product was more preferred by panellist than no fat-no salt chicken nuggets.
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Aeromonas are ubiquitous aquatic bacteria and frequently isolated from seafood. There is growing awareness of Aeromonas as foodborne pathogens, particularly in connection with consumption of ready-to-eat (RTE) seafood. The aim of this study was to investigate the effect of food processing factors on the growth kinetics of eight Aeromonas strains (representing seven species) isolated from RTE seafood. The effect of low temperature (4 and 8 °C) in combination with different NaCl concentrations (0.5-6.5 %) or with two purified condensate smokes (PCSs; Red Arrow SmokEz VTABB and JJT01) at different concentrations (0-0.26 %) was studied in Trypton Soy Broth (TSB). In food processing, application of PCS is considered healthier than traditional smoking. Growth kinetics parameters of each strain were estimated by using a primary predictive model. Our result showed that the addition of 3.5 % NaCl at refrigeration temperature (4 °C) was not sufficient to inhibit the growth of A. media, A. bestiarum, A. piscicola, and A. salmonicida, while higher NaCl concentration (≥5.0 %) at 8 °C suppressed their growth. On the other hand, our result demonstrated the antimicrobial potential of using PCS at maximal allowed concentration (0.26 %) against Aeromonas. PCS concentration and phenol content were important factors influencing the growth kinetics parameters of Aeromonas. Moreover, the growth kinetics of three Aeromonas strains were further studied in commercially produced vacuum-packed fresh and cold-smoked salmon stored at 4 °C for 14 and 21 days, respectively. Our results demonstrate that vacuum packing combined with cold storage at 4 °C was insufficient to inhibit the growth of Aeromonas in fresh salmon, while the growth was inhibited in a minimally salted cold-smoked salmon (salt content of 1.8 %). Our study implies that mild food processing factors applied in the production of RTE seafood might not guarantee the total inhibition of Aeromonas. Even though further studies on evaluating the antimicrobial potential of PCSs in actual seafood matrixes are necessary, the present study suggests that PCS technology might be a promising approach to prevent the potential growth of Aeromonas.
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Aeromonas , Listeria monocytogenes , Conservação de Alimentos/métodos , Embalagem de Alimentos/métodos , Cloreto de Sódio/farmacologia , Contagem de Colônia Microbiana , Manipulação de Alimentos/métodos , Alimentos Marinhos/microbiologia , Microbiologia de AlimentosRESUMO
Caiman meat is considered exotic and its consumption has significantly increased due to its nutritional quality. This study aimed to evaluate the kinetics of water content (WC) and salt content (SC) at different temperatures (1, 5, 10 and 15 °C) and to evaluate the use of mathematical models to predict the mass transfer kinetics until equilibrium conditions during the wet salting of caiman tail fillets. Moisture and chloride analyses were performed throughout the wet salting process. Four models (Peleg; Weibull; Zugarramurdi and Lupín; Diffusion) were tested to predict WC and SC kinetics in caiman tail fillets subjected to wet salting. The increase in the temperature resulted in a reduction (P < 0.05) in WC and an increase (P < 0.05) in SC. Nonlinear effects on WC and SC kinetics were observed between the different temperatures evaluated. Furthermore, the effective diffusion coefficients (Dw and Ds) increased (P < 0.05) with increasing temperature. Peleg, Weibull, Zugarramurdi and Lupín, and the Diffusion model satisfactorily represented WC and SC rates throughout the process. The kinetic behavior of the parameters of the models corroborated the effects of temperature on those parameters. Peleg was the best model for predicting WC and SC kinetics, and Zugarramurdi and Lupín was the best for predicting the equilibrium conditions of the process (WC∞ SC∞), all parameters which can be used to describe the mass transfer kinetics during wet salting of caiman tail fillets.
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Jacarés e Crocodilos , Animais , Temperatura , Sais , Cloreto de Sódio , Carne/análiseRESUMO
Hyperspectral technology has proven to be an effective method for monitoring soil salt content (SSC). However, hyperspectral estimation capabilities are limited when the soil surface is partially vegetated. This work aimed to (1) quantify the influences of different fraction vegetation coverage (FVC) on SSC estimation by hyperspectra and (2) explore the potential for a non-negative matrix factorization algorithm (NMF) to reduce the influence of various FVCs. Nine levels of mixed hyperspectra were measured from simulated mixed scenes, which were performed by strictly controlling SSC and FVC in the laboratory. NMF was implemented to extract soil spectral signals from mixed hyperspectra. The NMF-extracted soil spectra were used to estimate SSC using partial least squares regression. Results indicate that SSC could be estimated based on the original mixed spectra within a 25.76% FVC (R2cv = 0.68, RMSEcv = 5.18 g·kg-1, RPD = 1.43). Compared with the mixed spectra, NMF extraction of soil spectrum improved the estimation accuracy. The NMF-extracted soil spectra from FVC below 63.55% of the mixed spectra provided acceptable estimation accuracies for SSC with the lowest results of determination of the estimation R2cv = 0.69, RMSEcv = 4.15 g·kg-1, and RPD = 1.8. Additionally, we proposed a strategy for the model performance investigation that combines spearman correlation analysis and model variable importance projection analysis. The NMF-extracted soil spectra retained the sensitive wavelengths that were significantly correlated with SSC and participated in the operation as important variables of the model.
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Salinidade , Solo , Análise dos Mínimos Quadrados , Algoritmos , Cloreto de Sódio , Cloreto de Sódio na DietaRESUMO
Non-invasive technologies could help to guarantee quality standards of canned tuna fish. The aim of this study was to investigate the ability of bench-top (FT-NIR) and low-cost (LC-NIR) near infrared spectrometers to determine salt content and texture in canned tuna. Salt content distribution was also investigated using hyperspectral imaging (HSI) and computed tomography. Spectra were acquired on canned tuna and reference analysis performed. Partial least squares regression and discriminant analysis were used to develop salt content predictive and texture classification models. Salt content predictive errors were 0.10%, 0.22% and 0.22% for FT-NIR, LC-NIR and HSI, respectively. Salt content was not always homogeneously distributed in the can which was attributed to the salt content differences between internal and external parts of the tuna fish. Low-cost sensors could be a suitable solution to standardise the production and enable precise nutritional labelling, but more sophisticated algorithms are needed to identify textural defects.
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Alimentos Marinhos , Atum , Animais , Alimentos Marinhos/análise , Análise Discriminante , Análise dos Mínimos QuadradosRESUMO
Drought and salt stress are important abiotic stressors that adversely affect the growth, resistance and survival of plants. Haloxylon ammodendron is a strong halophyte, and its hydraulic characteristics and carbon metabolism response to drought and salt stress under natural conditions have not been widely studied. With H. ammodendron as the research object, three sample plots with different water and salt contents (high water and high salt, medium salt in reclaimed water, low water and low salt) were selected to determine their water physiology, photosynthetic physiology, carbon physiology and growth status under different water and salt conditions. Studies have shown that drought and salinity affect the hydraulic properties of H. ammodendron, reducing the water content and water potential of assimilation branches and secondary branches and increasing the hydraulic conductivity per unit cross-sectional area of biennial shoots. Affected by drought, the content of non-structural carbohydrates (NSCs) in assimilation branches and secondary branches was significantly reduced, and the NSC content of assimilating branches was significantly higher than that in secondary branches. The transportation of NSCs to the secondary branches caused obstacles, and more accumulated in the assimilating branches. In addition, drought reduced H. ammodendron photosynthesis and carbon assimilation and limited carbon uptake, resulting in slower growth. Under the influence of drought and salinity, the anisohydric properties of H. ammodendron weakened its stomatal regulation ability and made it susceptible to water transport obstacles, but the degree of carbon limitation was relatively small.
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The present work investigated the effects of water bath heating coupled with different ultrasound treatments on the gel properties, protein conformation, microstructures and chemical interactions of silver carp surimi at low/high salt levels. Results showed that the gel strength, hardness, springiness and water holding capacity (WHC) of surimi gels at low salt concentration were inferior to those at high salt content, regardless of the treatments. Compared with the traditional water bath heating, ultrasonic-assisted treatments significantly improved the gelation properties of surimi at the same salt level. In fact, ultrasound treatment also facilitated the unfolding of α-helix structure of the protein, with the resulting exposure of internal groups further enhancing hydrophobic interactions and hydrogen bonds between protein molecules, thereby leading to the formation of denser microstructures with smaller holes. Furthermore, the most noteworthy ultrasonic treatment group was ultrasound-assisted preheating (U + W) group, whose gelation performance under low salt condition, was comparable with that of the traditional two-stage heating (W + W) group with high salt content. Overall, ultrasound-assisted water bath preheating proved to be a feasible approach to improve the gel properties and microstructures of low-salt surimi gels.
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Carpas , Animais , Proteínas de Peixes/química , Manipulação de Alimentos/métodos , Géis/química , Calefação , ÁguaRESUMO
This study investigated the mechanism of glycerol, xylitol, and sorbitol-mediated curing of cured minced pork tenderloin. The use of polyhydroxy alcohol during mediated curing significantly reduced the salt content (p < 0.01) and water activity (aw) of the cured pork tenderloin. Low-field nuclear magnetic resonance (LFNMR) revealed that 1 % glycerol, 1 % xylitol, 1 % sorbitol, and 10 % glycerol-mediated curing decreased water mobility, and improved water holding capacity (WHC), and produced uniform dense microstructures. Raman spectroscopy and molecular docking indicated that polyhydroxy alcohols formed hydrogen bonds with myosin, as well as hydrogen bonds with free water molecules to convert free water into bound water to reduce aw, and altered the hydrophobic environment of myosin surface to reduce structural damage caused by high salt content. In conclusion, using polyhydroxy alcohol to mediate curing can effectively reduce the salt content of cured meat and provide a theoretical basis for its application in the cured meat industry.
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Soil salinization is one of key drivers for the degradation of soil quality and yield in arable land. To accurately and quickly evaluate soil salt content in Yinchuan Plain, field and indoor hyperspectral data were processed with first order differential (FDR) transformation, then the feature bands were identified by stepwise regression (SR). Partial least squares regression (PLSR) and support vector machines (SVM) were used to build models, which were verified to figure out the optimal hyperspectral type for the study area. Moreover, segmented and global corrections were performed to process poor hyperspectral, aiming to improve the accuracy of soil salt content inversion. The results showed that the accuracy of soil salt content inversion model based on field hyperspectral data was 58.9% higher than that of the indoor hyperspectral data. The accuracy of the inversion was improved through the segmented and global correction of the indoor hyperspectral. We found that the segmented correction is more accurate for the PLSR model (Rc2=0.790, Rp2=0.633, RPD=1.64) and the global correction is more accurate for the SVM model (Rc2=0.927, Rp2=0.947, RPD=3.87). The SVM models' inversion accuracy was higher than that of PLSR, with the field hyperspectral model fitted the best, followed by the indoor hyperspectral processed with the global correction and the indoor hyperspectral processed with the segmented correction, while the indoor hyperspectral the worst. Our results suggest that field hyperspectral data could contribute to the quantitative inversion of soil salt content in Yinchuan Plain. The corrected indoor hyperspectral could significantly enhance the inversion accuracy of soil salt content, which could guarantee food security and ecological quality development.
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Cloreto de Sódio , Solo , China , Análise dos Mínimos QuadradosRESUMO
Objective: To assess and compare the macronutrient and salt content in meat and dairy substitutes available on the Norwegian market. Design: Comparison between substitute products and two groups of meat and dairy products where one group represented the healthiest option (Keyhole) and one the most used option (Regular). Kruskal-Wallis test with pairwise comparison was conducted on categories with more than two groups, and Mann-Whitney U test was conducted on categories with two groups. Setting: Online stores in Norway. Hundred and two meat substitute products and 173 milk and dairy substitute products on sale spring and autumn 2020 were assessed; additionally, ninety-eight equivalent meat products and 105 milk and dairy products. Results: While Keyhole and Regular meat did not contain fibre, meat substitutes contained 3â 5-5â 0 g fibre per 100 g. The saturated fat content in meat substitutes was on average 1â 9 times lower than in Keyhole products and 5â 8 times lower than in Regular products. Milk and dairy substitutes contained 3â 2 and 3â 4 times less protein than Keyhole and Regular products, respectively. Conclusions: The study results indicate that meat and dairy substitutes on the Norwegian market vary in nutritional composition. Compared to Keyhole and Regular, substitutes contained lower levels of saturated fat, meat substitutes contained higher levels of fibre and milk and dairy substitutes less protein. Future studies should include content of micronutrients for a more comprehensive assessment.
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Carne , Nutrientes , Animais , Ácidos Graxos , Leite , NoruegaRESUMO
Salting and rehydration of myofibrils can be interfered with free radical diffusion process. This study investigated the effects of salt content (0, 1, 3 and 5%) and H2O2/ascorbate-based hydroxyl radical (OH)-generating system (1, 10, 20 mM H2O2) on the oxidation, conformation, aggregation, and thermal stability of porcine myofibrillar proteins (MPs). Results showed that 5% of salt inhibited carbonylation of MPs with intensive sulfhydryl loss and tryptophan quenching. Fourier transform infrared (FTIR), laser light scattering, and scanning electron microscopy (SEM) suggested that 20 mM H2O2 transformed more α-helix into ß-sheet of MPs, favoring larger aggregates being selectively exposed towards solvent during salt-induced fiber swelling. Oxidized MPs brined with ≤1% salt underwent partial unfolding with higher flexibility, while up to 5% of salt greatly hampered their hydration potential and weakened inter-fibrillar hydrogen bond with an improved protein solubility. Micro-rheology revealed that 1% of salt and 10 mM H2O2 rendered a denser structure of heat-set MPs gels.
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Peróxido de Hidrogênio , Miofibrilas , Animais , Géis , Oxirredução , Estresse Oxidativo , Reologia , SuínosRESUMO
Excessive soil salt content (SSC) seriously affects the crop growth and economic benefits in the agricultural production area. Prior research mainly focused on estimating the salinity in the top bare soil rather than in deep soil that is vital to crop growth. For this end, an experiment was carried out in the Hetao Irrigation District, Inner Mongolia, China. In the experiment, the SSC at different depths under vegetation was measured, and the Sentinel-1 radar images were obtained synchronously. The radar backscattering coefficients (VV and VH) were combined to construct multiple indices, whose sensitivity was then analyzed using the best subset selection (BSS). Meanwhile, four most commonly used algorithms, partial least squares regression (PLSR), quantile regression (QR), support vector machine (SVM), and extreme learning machine (ELM), were utilized to construct estimation models of salinity at the depths of 0-10, 10-20, 0-20, 20-40, 0-40, 40-60 and 0-60 cm before and after BSS, respectively. The results showed: (a) radar remote sensing can be used to estimate the salinity in the root zone of vegetation (0-30 cm); (b) after BSS, the correlation coefficients and estimation accuracy of the four monitoring models were all improved significantly; (c) the estimation accuracy of the four regression models was: SVM > QR > ELM > PLSR; and (d) among the seven sampling depths, 10-20 cm was the optimal inversion depth for all the four models, followed by 20-40 and 0-40 cm. Among the four models, SVM was higher in accuracy than the other three at 10-20 cm (RP 2 = 0.67, RMSEP = 0.12%). These findings can provide valuable guidance for soil salinity monitoring and agricultural production in the arid or semi-arid areas under vegetation.
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Tecnologia de Sensoriamento Remoto , Solo , Tecnologia de Sensoriamento Remoto/métodos , Radar , Cloreto de Sódio , Cloreto de Sódio na DietaRESUMO
This study aimed to analyze the fat, fatty acid profile, and salt content of restaurant foods (RFs) and find out strategies to lower them using the strengths, weaknesses, opportunities, and threats (SWOT). Five types of common foods (n = 70) were collected from restaurants in Tehran, Iran. The fat, fatty acid profile, and salt content of samples were analyzed by acid hydrolysis method, gas chromatography, and Charpentier Volhard methods, respectively. The quantitative data were analyzed by the SPSS using ANOVA and Spearman's correlation test. Then, a SWOT analysis was done. The laboratory results indicated that the highest amount of total fat was in Samosa (16.92% ± 6.27%), whereas saturated fatty acids (SFA) and trans fatty acids (TFA) were significantly higher in Koobideh kebab with rice (44.42% ± 5.07% and 2.86% ± 0.64%, respectively) as compared to other samples. In addition, the highest amount of salt was in the Falafel sandwich (2.87% ± 0.98%). The salt content in the majority of analyzed foods was about two times more than the daily recommendations of the World Health Organization (WHO). The SWOT analysis results showed the lack of standardization of recipes to measure accurate fat and salt content was the main weakness and food labeling in the menus was detected as an important opportunity. TFA and salt in RFs were alarmingly high and it is necessary to find strategies for reformulation of RFs to reduce their fat and salt content. Policymakers can use the SWOT analysis results of this study to offer directions for potential future strengthening actions of healthy foods in restaurants for public health.
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Surimi from silver carp with different salt contents (0-5%) was obtained treated by high intensity ultrasound (HIU, 100 kHz 91 W·cm-2). The gelation properties of samples were evaluated by puncture properties, microstructures, water-holding capacity, dynamic rheological properties and intermolecular interactions. As the salt content increased from 0 to 5%, gel properties of surimi without HIU significantly improved. For samples with low-salt (0-2% NaCl) content, HIU induced obvious enhancement in breaking force and deformation. HIU promoted the protein aggregation linked by SS bonds, hydrophobic interactions and non-disulfide covalent bonds in surimi gels with low-salt content. Moreover, microstructures of HIU surimi gels with low-salt content were more compact than those of the corresponding control samples. HIU also improved the gelation properties of surimi with 3% NaCl to an extent. However, for high-salt (4-5% NaCl) samples, HIU decreased the breaking force and deformation of surimi gels due to the degradation of proteins suggested by increased TCA-soluble peptides. In conclusion, HIU effectively improved the gelation properties of surimi with low-salt content (0-2% NaCl), but was harmful for high-salt (4-5% NaCl) surimi. This might provide the theoretical basis for the production of low-salt surimi gels.