The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,an...The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,and breakdown value to prepare LAB compound starter cultures.The results revealed that Latilactobacillus sakei HSD004 and Lacticaseibacillus rhamnosus HSD005 had apparent advantages in increasing the viscosity and reducing the setback and breakdown values of glutinous rice flour.In particular,the compound starter created using the two abovementioned LAB in the ratio of 3:1 had better performance than that using a single LAB in improving the pasting properties and increasing the water and oil absorption capacity of glutinous rice flour.Moreover,the gelatinization enthalpy of the fermented samples increased significantly.For frozen glutinous rice dough stored for 28 days,the viscoelasticity of frozen dough prepared by compound starter was better than that of control dough,and the freezable water content was lower than that of control dough.These results indicate that compound LAB fermentation is a promising technology in the glutinous rice-based food processing industry,which has significance for its application.展开更多
[Objective] The aim of this study was to explore the effects of storage temperature on pasting properties of brown rice.[Method] Rapid viscosity analyzer was used to determine the viscosity of brown rice under differe...[Objective] The aim of this study was to explore the effects of storage temperature on pasting properties of brown rice.[Method] Rapid viscosity analyzer was used to determine the viscosity of brown rice under different storage temperatures（30,25,20 and 15 ℃）.[Result] The peak viscosity value increased with storage time prolonging.The higher the storage temperature was,the more rapidly the increasing of peak viscosity value;different storage temperatures and storage time showed significant effects on peak viscosity value of brown rice;the difference on peak viscosity value of brown rice under different storage temperatures was significant.The hot viscosity value of brown rice stored under 30 and 25 ℃ gradually increased with the storage time prolonging;and storage time and storage temperature showed significant effects on hot viscosity value;there was extremely significant difference on hot viscosity value of brown rice under 30,25 and 20,15 ℃.The breakdown value showed a first increasing and then decreasing trend with the storage time prolonging;storage temperature and storage time had extremely significant effect on the breakdown value of brown rice;the breakdown value of brown rice among each storage temperature was extremely significant.The final viscosity of brown rice increased with storage time prolonging.The higher the temperature was,the higher the increasing rate of final viscosity;storage time and temperature showed extremely significant effect on the final viscosity of brown rice;the difference on final viscosity among different storage temperature treatments was extremely significant.The changes on setback value of brown rice under different storage temperature treatments were different with the storage time prolonging;and the storage temperature showed extremely significant effect on the setback value of brown rice.[Conclusion] The study had provided theoretical basis for the storage of brown rice.展开更多
The effect of gluten on pasting properties of wheat starch was studied to provide a scientific basis for the application of gluten in food production and quality improvement in wheat breeding. The pasting properties o...The effect of gluten on pasting properties of wheat starch was studied to provide a scientific basis for the application of gluten in food production and quality improvement in wheat breeding. The pasting properties of blends were analyzed using PH 1391 wheat starch mixed with five different additions of three kinds of gluten （strong-, medium-, and weak-gluten） and the structures of network were observed with microscope. The significant downtrends of peak viscosity, trough viscosity, final viscosity, area of viscosity, setback, and peak time were observed with the increase in the addition of gluten. In general, the average value of them decreased respectively by 3.6, 4.8, 3.4, 3.8, 4.0, and 1.18% of those corresponding indexes of pure starch for every 2% increase in gluten. The decreasing rate of the indexes mentioned above exceeded more than 2% except peak time, but there were no significant influence of gluten addition on breakdown, pasting temperature and pasting time. The inter layer composed of gluten was not observed when the addition of gluten was 10%, as the compound formed of gluten inlaid in the paste of starch, but obvious inter layer was detected when the addition of gluten was 18%. There was significant or remarkable difference among the effects of three different kinds of gluten on the peak viscosity, trough viscosity, area of viscosity, setback, and peak time, but it had no significant difference among the effects of different glutens on pasting temperature and pasting time. The descending order of the effect of different glutens on peak viscosity, trough viscosity, and area of viscosity was strong-, medium-, and weak-gluten, but the order of them for setback was opposite. Both addition and types of gluten significantly affected peak viscosity, trough viscosity, area of viscosity, setback, and peak time, but there were no significant effects of it on peak time and peak temperature.展开更多
Pasting properties are among the most important characteristics of starch, determining its applications in food processing and other industries. Pasting temperature derived from the Rapid Visco-analyser （RVA） （Newp...Pasting properties are among the most important characteristics of starch, determining its applications in food processing and other industries. Pasting temperature derived from the Rapid Visco-analyser （RVA） （Newport Scientific）, in most cases, is overestimated by the Thermocline for Windows software program. Here, two methods facilitating accurate measurement of pasting temperature by RVA were described. One is to change parameter setting to ＇screen＇ the true point where the pasting viscosity begins to increase, the other is to manually record the time （T1） when the pasting viscosity begins to increase and calculate the pasting temperature with the formula of （45/3.8）×（T1-1）＋50 for rice flour. The latter method gave a manually determined pasting temperature which was significantly correlated with the gelatinization temperature measured by differential scanning calorimetry.展开更多
As one of the most effective enzymatic modification methods of protein, papain hydrolysis is applied widely in food production, accompanying starch pasting frequently in order to improve industrial quality. Effects of...As one of the most effective enzymatic modification methods of protein, papain hydrolysis is applied widely in food production, accompanying starch pasting frequently in order to improve industrial quality. Effects of the papain hydrolysis on flour pasting properties were investigated in five papain/flour concentrations and five time-treatments. The structure of starch and protein networks in slurry was investigated under microscope before and after pasting. Results showed that papain hydrolysis influenced the pasting properties of wheat flour significantly through affecting structural characteristics, amylase activity and exotbermic transition, especially during the early stage of hydrolysis. Peak viscosity, trough, final, integral area, and setback significantly decreased along with the increasing concentration of papain. Both hydrolysis time and concentration of papain had obviously effect on the breakdown. Pasting temperature and pasting time increased significantly with the enhancement of papain concentration. Hydrolysis time exerted minor effect on the pasting temperature and pasting time. The average peak time was slightly prolonged by lower concentration of papain, otherwise slightly shortened by higher concentration.展开更多
Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of Chinese spring wheats....Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of Chinese spring wheats. Starch pasting properties were closely associated with noodle quality. Significant differences were observed for all pasting characteristics. Samples collected from Harbin, Shenyang, Beijing, Ba-meng, Yongning, and Urumqi had better pasting quality than those from other locations. Genotype, environment, and genotype by environment interaction had large effects on all pasting characteristics. Significant correlations among pasting characteristics were observed and peak viscosity was considered the most important pasting characteristics.展开更多
Lotus seed starch （15%, w/w） was subjected to ultra-high pressure （UHP） at 500 MPa for 10～60 min. The effects of UHP on the structural, pasting, and thermal properties of starch were investigated using solid-stat...Lotus seed starch （15%, w/w） was subjected to ultra-high pressure （UHP） at 500 MPa for 10～60 min. The effects of UHP on the structural, pasting, and thermal properties of starch were investigated using solid-state 13C CP/MAS NMR, differential scanning calorimetry （DSC）, HPSEC-MALLS-RI, and a rapid visco analyzer. The 13C CP/MAS NMR results revealed a reduction in the relative crystallinity and peak intensity of the crystalline state with increasing the UHP time. The molecular weight of native starch was 1.433 × 107 Da, which was higher than that of the UHP-treated starch. Viscograms of UHP-treated starch revealed an increase in paste viscosity, peak time, and pasting temperature and a reduction in breakdown and setback viscosity compared to the native starch. Furthermore, the DSC results showed a reduction in gelatinization temperature and gelatinization enthalpy with increasing the UHP time.展开更多
A rapid predictive method based on near-infrared re flectance spectroscopy(NIRS)of paddy rice was developed to measure the pasting properties of rice.The paddy rice samples were scanned by a near-infrared re flectance...A rapid predictive method based on near-infrared re flectance spectroscopy(NIRS)of paddy rice was developed to measure the pasting properties of rice.The paddy rice samples were scanned by a near-infrared re flectance spectrometer in the wavelength region of 1400–2400 nm and preprocessed by mathematical pretreatments prior to pasting properties analysis using a rapid visco-analyzer(RVA).The results indicated that the developed models of setback(SB),peak viscosity(PV),breakdown(BD)and consistency(CS)provided good prediction results with relatively high correlation coe±cients(0.81–0.96).In addition,the validity of the calibration models was statistically tested.Standard error of prediction(SEPT) and bias were small enough without any significance at 95% confidence interval.Nonetheless,this study proved that the use of NIRS for predicting pasting properties was feasible in paddy rice and could be applied in commercial trade and research.展开更多
Walnut (Juglansregia) seeds are edible rich source of several essential nutrients which can be processed into flour for several purposes. Composite flour blends (wheat/walnut flour) in the ratio of 100:0, 90:10, 80:20...Walnut (Juglansregia) seeds are edible rich source of several essential nutrients which can be processed into flour for several purposes. Composite flour blends (wheat/walnut flour) in the ratio of 100:0, 90:10, 80:20, 70:30, and 50:50 were produced and analyzed for proximate composition, functional properties and pasting properties using standard techniques. Proximate composition results indicated increased level of protein and fat (12.17% - 25.70% and 2.40% - 37.57%) respectively while carbohydrate decreased (63% - 19.4%) with increasing level of substitution with walnut flour. Functional analysis result indicated a decreasing level of bulk density and water absorption capacity (0.78% - 0.52% and 5.17% - 4.03%) respectively while swelling capacity increased (2.00% - 7.53%) with increasing level of walnut flour substitution. Pasting properties data indicated a decreasing level of pasting viscosity (92.69 - 42.30), trough (59.19 - 39.60) RVU, breakdown (33.55 - 2.92) RVU, final viscosity (252.09 - 95.51) RVU, setback (192.85 - 55.93) RVU with increasing level of walnut flour substitution. Results showed that supplementing wheat flour with walnut flour considerably improved the protein and fat content of the flour, hence they can find useful application for making of pastries like cakes and other snacks.展开更多
Chemical and functional properties of ten sweetpotato varieties were investigated. The sweetpotato were of various flesh colours which included orange, yellow, cream and white with dry matter content ranging from 30.2...Chemical and functional properties of ten sweetpotato varieties were investigated. The sweetpotato were of various flesh colours which included orange, yellow, cream and white with dry matter content ranging from 30.2% - 39.2%. The sweetpotato varieties varied significantly (p < 0.05) in total amylase activity, total starch and amylose content whose value ranges were 0.256 - 0.570 mg/ml/min 68.4% - 73.6%, 16.2% - 23.4% respectively. The pH of flours from the different sweetpotato varieties ranged from 6.01 - 6.64. The pasting behaviours of the sweetpotato flours also showed significant differences (p < 0.05) in the individual parameters (peak time, pasting temperature, peak viscosity, trough viscosity, final viscosity, breakdown and setback) among the different varieties. The results revealed the influence of variety on the chemical composition of sweetpotato and their pasting properties. Correlations were also revealed among different components of the sweetpotatoes which would be a basis in selection of the varieties for processing into different products.展开更多
Four oat β-glucan enriched hydrocolloids (Nutrim10, C-Trim20, C-Trim30, C-Trim50), oat bran concentrate (OBC), and β-Glucan95 were investigated for antioxidant and pasting properties. C-Trim30 had the highest solubl...Four oat β-glucan enriched hydrocolloids (Nutrim10, C-Trim20, C-Trim30, C-Trim50), oat bran concentrate (OBC), and β-Glucan95 were investigated for antioxidant and pasting properties. C-Trim30 had the highest soluble phenolic content, followed by C-Trim20. The trend of antioxidant activity was similar with that of phenolic contents. The phenolic content of the extracts increased with increasing temperatures. The highest content of soluble phenolic compounds was found at temperatures up to 100℃ for most samples regardless of solvent. Water extracts had significantly higher phenolic contents than extracts from 50% ethanol at 100℃ for all samples with the exception of C-Trim30. However, the effect of temperature and solvent concentrations was not as apparent for antioxidant activity as that observed for phenolic content. In general, the differences in three different solvents were not as apparent. Significantly higher water holding capacities were found for C-Trim30 and C-Trim50 than the other samples while β-Glucan 95 had substantially the highest paste viscosity followed by C-Trim50 and C-Trim30.展开更多
This research was aimed to evaluate the pasting properties of white corn flour made from Anoman 1 and Pulut Harapan varieties as affected by the fermentation process of the corn grits. The fermentation process studied...This research was aimed to evaluate the pasting properties of white corn flour made from Anoman 1 and Pulut Harapan varieties as affected by the fermentation process of the corn grits. The fermentation process studied were 1) spontaneous fermentation (SF);2) fermentation with the addition of a complete starter culture at 0 hour (CC fermentation) and 3) fermentation of (CC) with additional inoculation of starter culture containing amylolytic microorganisms at 16 hours (AC fermentation). The evaluation of pasting properties was done on the flour made from corn grits fermented for 0, 36, 48, and 72 hours. Our results showed that pasting properties of corn flour of Anoman 1 and Pulut Harapan varieties were affected by fermentation process. Addition of starter culture in the fermentation showed more complex effect on the pasting properties and was a function of the fermentation time. Fermentation process of corn grits affected the pasting properties of the resulted flour, both for Anoman I and Pulut Harapan corn varieties. The differences in the effect of fermentation process on the pasting properties were due to the different amylose/amylopectin content. AC fermentation of corn grits could increase the stability of paste for flour containing higher amylose content but decrease the stability of paste for flour containing high amylopectin. Specifically, CC fermentation caused significant increase in the peak viscosity value especially for corn flour of Pulut Harapan. Fermentation for up to 48 h had resulted in corn flour of Pulut Harapan variety having a higher PV value, but it did not affect the tendency to retrograde.展开更多
The objective of this research was to investigate the effect of Malva nut gum （MG） replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and free...The objective of this research was to investigate the effect of Malva nut gum （MG） replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and freeze-thaw stability of different flours incorporated with 0, 0.5%, 1%, 2%, 3% and 5% of MG were investigated. Pasting temperature （60 ℃-87 ℃） of the pastes significantly decreased with increasing of MG content for wheat and rice flours, but had no significant effect for waxy rice flour. Incorporation of MG into all flours significantly elevated the peak viscosity by about 0.9-2.6 folds when compared to non-MG samples. Hot paste viscosity, breakdown and final viscosity for all flour mixtures significantly increased with increasing of MG which ranged from 81-427, 37-559 and 152-463 RVU, respectively. Freeze-thaw stability measurement demonstrated that higher level of MG in wheat and rice gel mixtures could decrease syneresis. However, MG had no effect on syneresis of waxy rice gel. Presence of MG in flours alters the pasting properties and syneresis effect. It is suggested that higher viscosity and lower syneresis of gels could be modified by MG.展开更多
<span style="font-size:14px;">The use of hydrocolloids to modify the properties of native starches has been on the rise in the recent times due to the market demand for natural, safe and economical foo...<span style="font-size:14px;">The use of hydrocolloids to modify the properties of native starches has been on the rise in the recent times due to the market demand for natural, safe and economical food ingredients. The objective of this study was to investigate the effect of gum Arabic from </span><i><span style="font-size:14px;">Acacia senegal </span></i><span style="font-size:14px;">var.</span><i><span style="font-size:14px;"> kerensis</span></i><span style="font-size:14px;"> to modify pasting and textural properties of corn and cassava starches, as an alternative to chemical </span><span style="font-size:14px;">and enzymatic modification. Blends were prepared by substituting the starches </span><span style="font-size:14px;">with gum at different levels (0%, 0.5%, 2.0%, 4.0%, 6.0% and 8.0%), whereas native corn and cassava starches were used as control. The pasting properties of the starch-gum mixed systems were determined using the Brabender vis</span><span style="font-size:14px;">cograph while the textural properties (firmness, consistency, cohesiveness</span><span style="font-size:14px;"> and work of cohesion) were determined using Texture Analyzer. Results showed that the gum Arabic significantly decreased all the viscosity parameters</span><i> </i><span style="font-size:14px;">(peak viscosity, final viscosity, break down and setback values) of both starches at </span><span style="font-size:14px;">all levels of substitution. However, there was no significant effect of gum</span><span style="font-size:14px;"> Arabic on the pasting temperature (72.05</span><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:14px;">°C - 71.85</span><span style="font-size:14px;white-space:normal;">°</span><span style="font-size:14px;">C) for corn starch and (68.90</span><span style="font-size:14px;white-space:normal;">°</span><span style="font-size:14px;">C - 68.65</span><span style="font-size:14px;white-space:normal;">°</span><span style="font-size:14px;">C) for cassava starch. The degree of gel firmness and consistency was higher in corn starch than in cassava starch and the effect of gum addition </span><span style="font-size:14px;">differed with each starch. The findings from this study indicate that gum</span><span style="font-size:14px;"> Arabic significantly modified the pasting and textural properties of corn and cassava starches due to strong interaction between the gum and the starches. Hence, this property of gum Arabic could be useful in controlling starch retrogradation and determining starch end use functionality.</span></span>展开更多
Adjustment of the sowing date is a widely used measure in rice production for adapting to high-temperature conditions.However,the impact of a delayed sowing date(DS)on rice quality may vary by variety and ecological c...Adjustment of the sowing date is a widely used measure in rice production for adapting to high-temperature conditions.However,the impact of a delayed sowing date(DS)on rice quality may vary by variety and ecological conditions.In this study,we conducted experiments using four different sowing dates,the conventional sowing date 1(CS1),CS2(10 d later than CS1),DS1(30 d later than CS1),and DS2(30 d later than CS2),and three rice varieties,i.e.,Yixiangyou 2115,Fyou 498,and Chuanyou 6203.This experiment was conducted at four sites in the Sichuan Basin in 2018 and 2019 to evaluate the infuence of DS on the pasting properties of rice,which are a proxy for the eating and cooking quality(ECQ).In DS1 and DS2,the rice had a signifcantly greater amylose content(AC)but a lower protein content(PC),peak viscosity(PKV),cool paste viscosity(CPV),and hot paste viscosity(HPV)than in CS1 and CS2.Moreover,except for CS2 and DS1 in 2018,DS1 and DS2 led to 2.15-11.19%reductions in breakdown viscosity(BDV)and 23.46-108.47%increases in setback viscosity(SBV).However,the infuence of DS on rice pasting properties varied by study site and rice variety.In 2019,DS1 and DS2 led to BDV reductions of 2.35-9.33,2.61-8.61,10.03-17.78,and 2.06-8.93%,and SBV increases of 2.32-60.93,63.74-144.24,55.46-91.63,and-8.28-65.37%at the Dayi,Anzhou,Nanbu,and Shehong(except for SBV in CS2 and DS1)sites,respectively.DS resulted in greater reductions in PKV,HPV,CPV,and BDV and greater increases in the AC and SBV for Yixiangyou 2115 than for Chuanyou 6203 and Fyou 498.The correlation analysis indicated that PKV and HPV were signifcantly and positively related to the mean,maximum,and minimum temperatures after heading.These temperatures must be greater than 25.9,31.2,and 22.3℃,respectively,to increase the relative BDV and reduce the relative SBV of rice,thereby enhancing ECQ.In conclusion,DS might contribute to a signifcant deterioration in ECQ in machine-transplanted rice in the Sichuan Basin.A mean temperature above 25.9℃ after heading is required to improve the ECQ of rice.展开更多
The heat intolerance and retrogradation behavior of native wheat starch(WS)are undesirable for starch-based gel foods,therefore the combinations of WS and hydrocolloids have attracted extensive attentions.The objectiv...The heat intolerance and retrogradation behavior of native wheat starch(WS)are undesirable for starch-based gel foods,therefore the combinations of WS and hydrocolloids have attracted extensive attentions.The objectives of this study were to investigate the effects of konjac glucomannan(KGM)with different degree of deacetylation(DD)on the pasting,rheological and retrogradation properties of WS.Results showed that deacetyl-konjac glucomannan(DKGM)increased the peak viscosity(PV),trough viscosity(TV)and final viscosity(FV),while decreased the breakdown(BD)values of WS,suggesting the enhancement of the viscosity and thermal stability of WS paste.The raised storage modulus(G′)of WS gels with DKGM1(DD,48.23%)demonstrated that the partial removal of acetyl groups from KGM chains effectively promoted the formation of gel network,accompanied by increased elasticity.After storing at 4℃ for 7 days,the hardness of gels increased up 369%,while supplement with DKGM significantly(p<0.05)decreased the hardness.These data demonstrated that DKGM delayed the process of starch retrogradation,which was further verified by LF-NMR analysis.Besides,the addition of DKGM reduced the retrogradation rate,relative crystallinity and the orderliness of WS-DKGM gels with the prolonging of storage at 4℃,all validating the hindrance of starch retrogradation by DKGM.Therefore,these data suggested that partial deacetylation of KGM could effectively improve the pasting,rheological characteristics and impede the retrogradation of WS.展开更多
Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly as...Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash paste.We conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the samples.The mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were investigated.The results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased significantly.When the content exceeded 4%,the rate of increase in strength decreased.Based on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping conditions.The activation effect was poor for long-term strength after 28 days.The CaO content did not significantly affect the degree of activation achieved.The maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the system.The activators also corroded the surface of the fly ash particles,resulting in a pozzolanic reaction.The active substances in fly ash were released efficiently,and hydration was realized.The pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.展开更多
Pear paste is a traditional preparation with both medicinal and nutritional functions.The“pear”,as its core ingredient,plays a crucial role in the efficacy of the preparation.This paper,through the interdisciplinary...Pear paste is a traditional preparation with both medicinal and nutritional functions.The“pear”,as its core ingredient,plays a crucial role in the efficacy of the preparation.This paper,through the interdisciplinary integration of evidence from traditional Chinese medicine,food chemistry,molecular biology,and clinical medicine,constructs a complete“raw material-component transformation-biological regulation”model for the first time.It is found that in pear paste,pears not only serve as a functional matrix.The polysaccharide-polyphenol-triterpene complex system forms a multi-target cough-relieving and anti-inflammatory network through dual regulation of TRPV1/TRPA1 ion channels,inhibition of the NLRP3 inflammasome,and metabolites of gut microbiota such as SCFAs.The research results provide a theoretical breakthrough for the modern development of pear paste and a scientific basis for the modernization of traditional preparations.展开更多
Aceh in Indonesia is rich inmarine resources and abundant fishery products such as oyster.Traditionally,fishermen only harvest oysters and discard the shells,which can cause pollution and environmental contamination.W...Aceh in Indonesia is rich inmarine resources and abundant fishery products such as oyster.Traditionally,fishermen only harvest oysters and discard the shells,which can cause pollution and environmental contamination.Waste Oyster Shells(WOS)contain a high percentage of calcium carbonate(CaCO_(3))that experiences thermal decomposition at high temperature,following the reaction CaCO_(3)→CaO+CO_(2)(ΔT=825℃).At temperature>900℃,dead-burned lime is formed,which severely influences CaO reactivity.However,the optimum temperature for producing high CaO content is still uncertain.Therefore,this study aimed to determine the optimum calcination temperature to produce high CaO content,assess initial setting time of WOS paste,and identify the best compressive strength of paste.For the experiment,WOS was used as a partial cement replacement(with a size of 0.075 mm)in paste at a proportion of 5%and calcined at temperature of 700℃,800℃,900℃,and 1000℃.The specimens used were an ebonite ring(dimensions:70 mm bottom diameter,60 mm top diameter,and 40 mm height)and a cube(dimensions:5 cm×5 cm×5 cm).The experiment was conducted following the ASTM(American Society for Testing andMaterials)standards and optimumcompressive strength values were analyzed using ANOVA(Analysis of Variance)and Response Surface Methodology(RSM)through the Design Expert software.The results showed that WOS calcined at 1000℃ increased CaO content by approximately 57.40%.Furthermore,the initial setting time test of 5%WOS paste at 1000℃ showed a more uniform binding performance compared to conventional cement paste,with an initial setting time of 75 min and a penetration depth of 15 mm.In line with the analysis,optimum compressive strength of 71.028 MPa with a desirability value of 0.986 was achieved at 5%cement replacement and calcination temperature of 786.44℃.展开更多
With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.T...With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.To enhance the mechanical properties of CPB materials,fiber reinforcement technology has gradually gained attention,though challenges remain in predicting its performance.This study develops a hybrid model based on the adaptive equilibrium optimizer(adap-EO)-enhanced XGBoost method for accurately predicting the uniaxial compressive strength of fiber-reinforced CPB.Through systematic comparison with various other machine learning methods,results demonstrate that the proposed hybridmodel exhibits excellent predictive performance on the test set,achieving a coefficient of determination(R^(2))of 0.9675,root mean square error(RMSE)of 0.6084,and mean absolute error(MAE)of 0.4620.Input importance analysis reveals that cement-tailings ratio,curing time,and concentration are the three most critical factors affectingmaterial strength,with cement-tailings ratio showing a positive correlation with strength,concentrations above 70% significantly improvingmaterial strength,and curing periods beyond 28 days being essential for strength development.Fiber parameters contribute secondarily but notably to material strength,with fiber length exhibiting an optimal range of approximately 12 mm.This study not only provides a high-precision strength prediction model but also reveals the inherent correlations between various parameters and material performance,offering scientific basis for mixture optimization and engineering applications of fiber-reinforced CPB materials.展开更多
基金supported by the National Key Research and Development Program of China(2021YFD2100902-3)the National Natural Science Foundation of China(32072258)+5 种基金Major Science and Technology Program of Heilongjiang(2020ZX08B02)Harbin University of Commerce“Young Innovative Talents”Support Program(2019CX062020CX262020CX27)the Central Financial Support for the Development of Local Colleges and Universities,Graduate Innovation Research Project of Harbin University of Commerce(YJSCX2021-698HSD)Training plan of Young Innovative Talents in Universities of Heilongjiang(UNPYSCT-2020218).
文摘The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,and breakdown value to prepare LAB compound starter cultures.The results revealed that Latilactobacillus sakei HSD004 and Lacticaseibacillus rhamnosus HSD005 had apparent advantages in increasing the viscosity and reducing the setback and breakdown values of glutinous rice flour.In particular,the compound starter created using the two abovementioned LAB in the ratio of 3:1 had better performance than that using a single LAB in improving the pasting properties and increasing the water and oil absorption capacity of glutinous rice flour.Moreover,the gelatinization enthalpy of the fermented samples increased significantly.For frozen glutinous rice dough stored for 28 days,the viscoelasticity of frozen dough prepared by compound starter was better than that of control dough,and the freezable water content was lower than that of control dough.These results indicate that compound LAB fermentation is a promising technology in the glutinous rice-based food processing industry,which has significance for its application.
基金Supported by "Eleventh Five-Year "National Science and Technology Ministry Support Project(2006BAD08B03-3)~~
文摘[Objective] The aim of this study was to explore the effects of storage temperature on pasting properties of brown rice.[Method] Rapid viscosity analyzer was used to determine the viscosity of brown rice under different storage temperatures（30,25,20 and 15 ℃）.[Result] The peak viscosity value increased with storage time prolonging.The higher the storage temperature was,the more rapidly the increasing of peak viscosity value;different storage temperatures and storage time showed significant effects on peak viscosity value of brown rice;the difference on peak viscosity value of brown rice under different storage temperatures was significant.The hot viscosity value of brown rice stored under 30 and 25 ℃ gradually increased with the storage time prolonging;and storage time and storage temperature showed significant effects on hot viscosity value;there was extremely significant difference on hot viscosity value of brown rice under 30,25 and 20,15 ℃.The breakdown value showed a first increasing and then decreasing trend with the storage time prolonging;storage temperature and storage time had extremely significant effect on the breakdown value of brown rice;the breakdown value of brown rice among each storage temperature was extremely significant.The final viscosity of brown rice increased with storage time prolonging.The higher the temperature was,the higher the increasing rate of final viscosity;storage time and temperature showed extremely significant effect on the final viscosity of brown rice;the difference on final viscosity among different storage temperature treatments was extremely significant.The changes on setback value of brown rice under different storage temperature treatments were different with the storage time prolonging;and the storage temperature showed extremely significant effect on the setback value of brown rice.[Conclusion] The study had provided theoretical basis for the storage of brown rice.
基金supported by the National Basic Research Program of China (973Program,2009CB118300)the Improved Variety Project of Shandong Province,China (LN2008-167)the Youth Science and Technology Innovation funded by the Shandong Agricultural University,China (005-23601)
文摘The effect of gluten on pasting properties of wheat starch was studied to provide a scientific basis for the application of gluten in food production and quality improvement in wheat breeding. The pasting properties of blends were analyzed using PH 1391 wheat starch mixed with five different additions of three kinds of gluten （strong-, medium-, and weak-gluten） and the structures of network were observed with microscope. The significant downtrends of peak viscosity, trough viscosity, final viscosity, area of viscosity, setback, and peak time were observed with the increase in the addition of gluten. In general, the average value of them decreased respectively by 3.6, 4.8, 3.4, 3.8, 4.0, and 1.18% of those corresponding indexes of pure starch for every 2% increase in gluten. The decreasing rate of the indexes mentioned above exceeded more than 2% except peak time, but there were no significant influence of gluten addition on breakdown, pasting temperature and pasting time. The inter layer composed of gluten was not observed when the addition of gluten was 10%, as the compound formed of gluten inlaid in the paste of starch, but obvious inter layer was detected when the addition of gluten was 18%. There was significant or remarkable difference among the effects of three different kinds of gluten on the peak viscosity, trough viscosity, area of viscosity, setback, and peak time, but it had no significant difference among the effects of different glutens on pasting temperature and pasting time. The descending order of the effect of different glutens on peak viscosity, trough viscosity, and area of viscosity was strong-, medium-, and weak-gluten, but the order of them for setback was opposite. Both addition and types of gluten significantly affected peak viscosity, trough viscosity, area of viscosity, setback, and peak time, but there were no significant effects of it on peak time and peak temperature.
基金This research was financially supported in part by the National High Technology Development Project of China(Grant No.2006AA10Z193)the National Natural Science Foundation of China(Grant No.30300227)the Science and Technology Department of Zhejiang Province(Grant No.2007C32014).
文摘Pasting properties are among the most important characteristics of starch, determining its applications in food processing and other industries. Pasting temperature derived from the Rapid Visco-analyser （RVA） （Newport Scientific）, in most cases, is overestimated by the Thermocline for Windows software program. Here, two methods facilitating accurate measurement of pasting temperature by RVA were described. One is to change parameter setting to ＇screen＇ the true point where the pasting viscosity begins to increase, the other is to manually record the time （T1） when the pasting viscosity begins to increase and calculate the pasting temperature with the formula of （45/3.8）×（T1-1）＋50 for rice flour. The latter method gave a manually determined pasting temperature which was significantly correlated with the gelatinization temperature measured by differential scanning calorimetry.
基金supported by the National Natural Science Foundation of China(31171554)the National Basic Research Program of China(2009CB118300)the Improved Variety Project of Shandong Province, China(LN2008-167)
文摘As one of the most effective enzymatic modification methods of protein, papain hydrolysis is applied widely in food production, accompanying starch pasting frequently in order to improve industrial quality. Effects of the papain hydrolysis on flour pasting properties were investigated in five papain/flour concentrations and five time-treatments. The structure of starch and protein networks in slurry was investigated under microscope before and after pasting. Results showed that papain hydrolysis influenced the pasting properties of wheat flour significantly through affecting structural characteristics, amylase activity and exotbermic transition, especially during the early stage of hydrolysis. Peak viscosity, trough, final, integral area, and setback significantly decreased along with the increasing concentration of papain. Both hydrolysis time and concentration of papain had obviously effect on the breakdown. Pasting temperature and pasting time increased significantly with the enhancement of papain concentration. Hydrolysis time exerted minor effect on the pasting temperature and pasting time. The average peak time was slightly prolonged by lower concentration of papain, otherwise slightly shortened by higher concentration.
基金the NationalNatural Science Foundation of China(300600433 and 39930110).
文摘Forty-seven spring wheat Triticumaestivum cultivars and advanced lines from spring-sown spring wheat regions, at twelve locations in 1998 and 1999, were used to investigate pasting properties of Chinese spring wheats. Starch pasting properties were closely associated with noodle quality. Significant differences were observed for all pasting characteristics. Samples collected from Harbin, Shenyang, Beijing, Ba-meng, Yongning, and Urumqi had better pasting quality than those from other locations. Genotype, environment, and genotype by environment interaction had large effects on all pasting characteristics. Significant correlations among pasting characteristics were observed and peak viscosity was considered the most important pasting characteristics.
基金Supported by the Cooperation in Production,Study and Research of Science and Technology Major Projects of Fujian Province(2012N5004)the Natural Science Foundation of Fujian Province(2012J01081)+1 种基金the Scientific and Technological Innovation Team Support Plan of Institution of Higher Learning in Fujian Province([2012]03)the Scientific and Technological Innovation Team Support Plan of Fujian Agriculture and Forestry University(cxtd12009)
文摘Lotus seed starch （15%, w/w） was subjected to ultra-high pressure （UHP） at 500 MPa for 10～60 min. The effects of UHP on the structural, pasting, and thermal properties of starch were investigated using solid-state 13C CP/MAS NMR, differential scanning calorimetry （DSC）, HPSEC-MALLS-RI, and a rapid visco analyzer. The 13C CP/MAS NMR results revealed a reduction in the relative crystallinity and peak intensity of the crystalline state with increasing the UHP time. The molecular weight of native starch was 1.433 × 107 Da, which was higher than that of the UHP-treated starch. Viscograms of UHP-treated starch revealed an increase in paste viscosity, peak time, and pasting temperature and a reduction in breakdown and setback viscosity compared to the native starch. Furthermore, the DSC results showed a reduction in gelatinization temperature and gelatinization enthalpy with increasing the UHP time.
文摘A rapid predictive method based on near-infrared re flectance spectroscopy(NIRS)of paddy rice was developed to measure the pasting properties of rice.The paddy rice samples were scanned by a near-infrared re flectance spectrometer in the wavelength region of 1400–2400 nm and preprocessed by mathematical pretreatments prior to pasting properties analysis using a rapid visco-analyzer(RVA).The results indicated that the developed models of setback(SB),peak viscosity(PV),breakdown(BD)and consistency(CS)provided good prediction results with relatively high correlation coe±cients(0.81–0.96).In addition,the validity of the calibration models was statistically tested.Standard error of prediction(SEPT) and bias were small enough without any significance at 95% confidence interval.Nonetheless,this study proved that the use of NIRS for predicting pasting properties was feasible in paddy rice and could be applied in commercial trade and research.
文摘Walnut (Juglansregia) seeds are edible rich source of several essential nutrients which can be processed into flour for several purposes. Composite flour blends (wheat/walnut flour) in the ratio of 100:0, 90:10, 80:20, 70:30, and 50:50 were produced and analyzed for proximate composition, functional properties and pasting properties using standard techniques. Proximate composition results indicated increased level of protein and fat (12.17% - 25.70% and 2.40% - 37.57%) respectively while carbohydrate decreased (63% - 19.4%) with increasing level of substitution with walnut flour. Functional analysis result indicated a decreasing level of bulk density and water absorption capacity (0.78% - 0.52% and 5.17% - 4.03%) respectively while swelling capacity increased (2.00% - 7.53%) with increasing level of walnut flour substitution. Pasting properties data indicated a decreasing level of pasting viscosity (92.69 - 42.30), trough (59.19 - 39.60) RVU, breakdown (33.55 - 2.92) RVU, final viscosity (252.09 - 95.51) RVU, setback (192.85 - 55.93) RVU with increasing level of walnut flour substitution. Results showed that supplementing wheat flour with walnut flour considerably improved the protein and fat content of the flour, hence they can find useful application for making of pastries like cakes and other snacks.
文摘Chemical and functional properties of ten sweetpotato varieties were investigated. The sweetpotato were of various flesh colours which included orange, yellow, cream and white with dry matter content ranging from 30.2% - 39.2%. The sweetpotato varieties varied significantly (p < 0.05) in total amylase activity, total starch and amylose content whose value ranges were 0.256 - 0.570 mg/ml/min 68.4% - 73.6%, 16.2% - 23.4% respectively. The pH of flours from the different sweetpotato varieties ranged from 6.01 - 6.64. The pasting behaviours of the sweetpotato flours also showed significant differences (p < 0.05) in the individual parameters (peak time, pasting temperature, peak viscosity, trough viscosity, final viscosity, breakdown and setback) among the different varieties. The results revealed the influence of variety on the chemical composition of sweetpotato and their pasting properties. Correlations were also revealed among different components of the sweetpotatoes which would be a basis in selection of the varieties for processing into different products.
文摘Four oat β-glucan enriched hydrocolloids (Nutrim10, C-Trim20, C-Trim30, C-Trim50), oat bran concentrate (OBC), and β-Glucan95 were investigated for antioxidant and pasting properties. C-Trim30 had the highest soluble phenolic content, followed by C-Trim20. The trend of antioxidant activity was similar with that of phenolic contents. The phenolic content of the extracts increased with increasing temperatures. The highest content of soluble phenolic compounds was found at temperatures up to 100℃ for most samples regardless of solvent. Water extracts had significantly higher phenolic contents than extracts from 50% ethanol at 100℃ for all samples with the exception of C-Trim30. However, the effect of temperature and solvent concentrations was not as apparent for antioxidant activity as that observed for phenolic content. In general, the differences in three different solvents were not as apparent. Significantly higher water holding capacities were found for C-Trim30 and C-Trim50 than the other samples while β-Glucan 95 had substantially the highest paste viscosity followed by C-Trim50 and C-Trim30.
文摘This research was aimed to evaluate the pasting properties of white corn flour made from Anoman 1 and Pulut Harapan varieties as affected by the fermentation process of the corn grits. The fermentation process studied were 1) spontaneous fermentation (SF);2) fermentation with the addition of a complete starter culture at 0 hour (CC fermentation) and 3) fermentation of (CC) with additional inoculation of starter culture containing amylolytic microorganisms at 16 hours (AC fermentation). The evaluation of pasting properties was done on the flour made from corn grits fermented for 0, 36, 48, and 72 hours. Our results showed that pasting properties of corn flour of Anoman 1 and Pulut Harapan varieties were affected by fermentation process. Addition of starter culture in the fermentation showed more complex effect on the pasting properties and was a function of the fermentation time. Fermentation process of corn grits affected the pasting properties of the resulted flour, both for Anoman I and Pulut Harapan corn varieties. The differences in the effect of fermentation process on the pasting properties were due to the different amylose/amylopectin content. AC fermentation of corn grits could increase the stability of paste for flour containing higher amylose content but decrease the stability of paste for flour containing high amylopectin. Specifically, CC fermentation caused significant increase in the peak viscosity value especially for corn flour of Pulut Harapan. Fermentation for up to 48 h had resulted in corn flour of Pulut Harapan variety having a higher PV value, but it did not affect the tendency to retrograde.
文摘The objective of this research was to investigate the effect of Malva nut gum （MG） replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and freeze-thaw stability of different flours incorporated with 0, 0.5%, 1%, 2%, 3% and 5% of MG were investigated. Pasting temperature （60 ℃-87 ℃） of the pastes significantly decreased with increasing of MG content for wheat and rice flours, but had no significant effect for waxy rice flour. Incorporation of MG into all flours significantly elevated the peak viscosity by about 0.9-2.6 folds when compared to non-MG samples. Hot paste viscosity, breakdown and final viscosity for all flour mixtures significantly increased with increasing of MG which ranged from 81-427, 37-559 and 152-463 RVU, respectively. Freeze-thaw stability measurement demonstrated that higher level of MG in wheat and rice gel mixtures could decrease syneresis. However, MG had no effect on syneresis of waxy rice gel. Presence of MG in flours alters the pasting properties and syneresis effect. It is suggested that higher viscosity and lower syneresis of gels could be modified by MG.
文摘<span style="font-size:14px;">The use of hydrocolloids to modify the properties of native starches has been on the rise in the recent times due to the market demand for natural, safe and economical food ingredients. The objective of this study was to investigate the effect of gum Arabic from </span><i><span style="font-size:14px;">Acacia senegal </span></i><span style="font-size:14px;">var.</span><i><span style="font-size:14px;"> kerensis</span></i><span style="font-size:14px;"> to modify pasting and textural properties of corn and cassava starches, as an alternative to chemical </span><span style="font-size:14px;">and enzymatic modification. Blends were prepared by substituting the starches </span><span style="font-size:14px;">with gum at different levels (0%, 0.5%, 2.0%, 4.0%, 6.0% and 8.0%), whereas native corn and cassava starches were used as control. The pasting properties of the starch-gum mixed systems were determined using the Brabender vis</span><span style="font-size:14px;">cograph while the textural properties (firmness, consistency, cohesiveness</span><span style="font-size:14px;"> and work of cohesion) were determined using Texture Analyzer. Results showed that the gum Arabic significantly decreased all the viscosity parameters</span><i> </i><span style="font-size:14px;">(peak viscosity, final viscosity, break down and setback values) of both starches at </span><span style="font-size:14px;">all levels of substitution. However, there was no significant effect of gum</span><span style="font-size:14px;"> Arabic on the pasting temperature (72.05</span><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:14px;">°C - 71.85</span><span style="font-size:14px;white-space:normal;">°</span><span style="font-size:14px;">C) for corn starch and (68.90</span><span style="font-size:14px;white-space:normal;">°</span><span style="font-size:14px;">C - 68.65</span><span style="font-size:14px;white-space:normal;">°</span><span style="font-size:14px;">C) for cassava starch. The degree of gel firmness and consistency was higher in corn starch than in cassava starch and the effect of gum addition </span><span style="font-size:14px;">differed with each starch. The findings from this study indicate that gum</span><span style="font-size:14px;"> Arabic significantly modified the pasting and textural properties of corn and cassava starches due to strong interaction between the gum and the starches. Hence, this property of gum Arabic could be useful in controlling starch retrogradation and determining starch end use functionality.</span></span>
基金supported by the National Natural Science Foundation of China(U20A2022 and 32372217)the National Key Research and Development Program of China(2022YFD2300700)the Free Exploration Program of State Key Laboratory of Crop Gene Exploration and Utilization in Sichuan Basin,China(SKL-ZY202216)。
文摘Adjustment of the sowing date is a widely used measure in rice production for adapting to high-temperature conditions.However,the impact of a delayed sowing date(DS)on rice quality may vary by variety and ecological conditions.In this study,we conducted experiments using four different sowing dates,the conventional sowing date 1(CS1),CS2(10 d later than CS1),DS1(30 d later than CS1),and DS2(30 d later than CS2),and three rice varieties,i.e.,Yixiangyou 2115,Fyou 498,and Chuanyou 6203.This experiment was conducted at four sites in the Sichuan Basin in 2018 and 2019 to evaluate the infuence of DS on the pasting properties of rice,which are a proxy for the eating and cooking quality(ECQ).In DS1 and DS2,the rice had a signifcantly greater amylose content(AC)but a lower protein content(PC),peak viscosity(PKV),cool paste viscosity(CPV),and hot paste viscosity(HPV)than in CS1 and CS2.Moreover,except for CS2 and DS1 in 2018,DS1 and DS2 led to 2.15-11.19%reductions in breakdown viscosity(BDV)and 23.46-108.47%increases in setback viscosity(SBV).However,the infuence of DS on rice pasting properties varied by study site and rice variety.In 2019,DS1 and DS2 led to BDV reductions of 2.35-9.33,2.61-8.61,10.03-17.78,and 2.06-8.93%,and SBV increases of 2.32-60.93,63.74-144.24,55.46-91.63,and-8.28-65.37%at the Dayi,Anzhou,Nanbu,and Shehong(except for SBV in CS2 and DS1)sites,respectively.DS resulted in greater reductions in PKV,HPV,CPV,and BDV and greater increases in the AC and SBV for Yixiangyou 2115 than for Chuanyou 6203 and Fyou 498.The correlation analysis indicated that PKV and HPV were signifcantly and positively related to the mean,maximum,and minimum temperatures after heading.These temperatures must be greater than 25.9,31.2,and 22.3℃,respectively,to increase the relative BDV and reduce the relative SBV of rice,thereby enhancing ECQ.In conclusion,DS might contribute to a signifcant deterioration in ECQ in machine-transplanted rice in the Sichuan Basin.A mean temperature above 25.9℃ after heading is required to improve the ECQ of rice.
基金This study was supported by the National Key Research and Development Program of China during the 13th Five-Year Plan(2018YFD0400501)Key Research and development plan for Colleges and Universities in Henan Province(20A550013).
文摘The heat intolerance and retrogradation behavior of native wheat starch(WS)are undesirable for starch-based gel foods,therefore the combinations of WS and hydrocolloids have attracted extensive attentions.The objectives of this study were to investigate the effects of konjac glucomannan(KGM)with different degree of deacetylation(DD)on the pasting,rheological and retrogradation properties of WS.Results showed that deacetyl-konjac glucomannan(DKGM)increased the peak viscosity(PV),trough viscosity(TV)and final viscosity(FV),while decreased the breakdown(BD)values of WS,suggesting the enhancement of the viscosity and thermal stability of WS paste.The raised storage modulus(G′)of WS gels with DKGM1(DD,48.23%)demonstrated that the partial removal of acetyl groups from KGM chains effectively promoted the formation of gel network,accompanied by increased elasticity.After storing at 4℃ for 7 days,the hardness of gels increased up 369%,while supplement with DKGM significantly(p<0.05)decreased the hardness.These data demonstrated that DKGM delayed the process of starch retrogradation,which was further verified by LF-NMR analysis.Besides,the addition of DKGM reduced the retrogradation rate,relative crystallinity and the orderliness of WS-DKGM gels with the prolonging of storage at 4℃,all validating the hindrance of starch retrogradation by DKGM.Therefore,these data suggested that partial deacetylation of KGM could effectively improve the pasting,rheological characteristics and impede the retrogradation of WS.
基金Supported by Yunnan Major Scientific and Technological Projects(No.202403AA080001)National Natural Science Foundation of China(No.52074137)Yunnan Fundamental Research Projects(No.202201AT070151)。
文摘Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash paste.We conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the samples.The mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were investigated.The results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased significantly.When the content exceeded 4%,the rate of increase in strength decreased.Based on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping conditions.The activation effect was poor for long-term strength after 28 days.The CaO content did not significantly affect the degree of activation achieved.The maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the system.The activators also corroded the surface of the fly ash particles,resulting in a pozzolanic reaction.The active substances in fly ash were released efficiently,and hydration was realized.The pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.
基金Science and Technology Achievements Transformation Project of the Autonomous Prefecture(Project No.:202401)National College Students'Innovation and Entrepreneurship Training Program(Project Title:"Li Zhiyun·Ku Li Chun"-Pioneer in Promoting National Geographic Brand,Project Number:202513561005).
文摘Pear paste is a traditional preparation with both medicinal and nutritional functions.The“pear”,as its core ingredient,plays a crucial role in the efficacy of the preparation.This paper,through the interdisciplinary integration of evidence from traditional Chinese medicine,food chemistry,molecular biology,and clinical medicine,constructs a complete“raw material-component transformation-biological regulation”model for the first time.It is found that in pear paste,pears not only serve as a functional matrix.The polysaccharide-polyphenol-triterpene complex system forms a multi-target cough-relieving and anti-inflammatory network through dual regulation of TRPV1/TRPA1 ion channels,inhibition of the NLRP3 inflammasome,and metabolites of gut microbiota such as SCFAs.The research results provide a theoretical breakthrough for the modern development of pear paste and a scientific basis for the modernization of traditional preparations.
文摘Aceh in Indonesia is rich inmarine resources and abundant fishery products such as oyster.Traditionally,fishermen only harvest oysters and discard the shells,which can cause pollution and environmental contamination.Waste Oyster Shells(WOS)contain a high percentage of calcium carbonate(CaCO_(3))that experiences thermal decomposition at high temperature,following the reaction CaCO_(3)→CaO+CO_(2)(ΔT=825℃).At temperature>900℃,dead-burned lime is formed,which severely influences CaO reactivity.However,the optimum temperature for producing high CaO content is still uncertain.Therefore,this study aimed to determine the optimum calcination temperature to produce high CaO content,assess initial setting time of WOS paste,and identify the best compressive strength of paste.For the experiment,WOS was used as a partial cement replacement(with a size of 0.075 mm)in paste at a proportion of 5%and calcined at temperature of 700℃,800℃,900℃,and 1000℃.The specimens used were an ebonite ring(dimensions:70 mm bottom diameter,60 mm top diameter,and 40 mm height)and a cube(dimensions:5 cm×5 cm×5 cm).The experiment was conducted following the ASTM(American Society for Testing andMaterials)standards and optimumcompressive strength values were analyzed using ANOVA(Analysis of Variance)and Response Surface Methodology(RSM)through the Design Expert software.The results showed that WOS calcined at 1000℃ increased CaO content by approximately 57.40%.Furthermore,the initial setting time test of 5%WOS paste at 1000℃ showed a more uniform binding performance compared to conventional cement paste,with an initial setting time of 75 min and a penetration depth of 15 mm.In line with the analysis,optimum compressive strength of 71.028 MPa with a desirability value of 0.986 was achieved at 5%cement replacement and calcination temperature of 786.44℃.
基金funded by the National Natural Science Foundation of China(Grant 42177164)the Distinguished Youth Science Foundation of Hunan Province of China(2022JJ10073)supported by China Scholarship Council with the grant number of 202006370006.
文摘With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.To enhance the mechanical properties of CPB materials,fiber reinforcement technology has gradually gained attention,though challenges remain in predicting its performance.This study develops a hybrid model based on the adaptive equilibrium optimizer(adap-EO)-enhanced XGBoost method for accurately predicting the uniaxial compressive strength of fiber-reinforced CPB.Through systematic comparison with various other machine learning methods,results demonstrate that the proposed hybridmodel exhibits excellent predictive performance on the test set,achieving a coefficient of determination(R^(2))of 0.9675,root mean square error(RMSE)of 0.6084,and mean absolute error(MAE)of 0.4620.Input importance analysis reveals that cement-tailings ratio,curing time,and concentration are the three most critical factors affectingmaterial strength,with cement-tailings ratio showing a positive correlation with strength,concentrations above 70% significantly improvingmaterial strength,and curing periods beyond 28 days being essential for strength development.Fiber parameters contribute secondarily but notably to material strength,with fiber length exhibiting an optimal range of approximately 12 mm.This study not only provides a high-precision strength prediction model but also reveals the inherent correlations between various parameters and material performance,offering scientific basis for mixture optimization and engineering applications of fiber-reinforced CPB materials.
