The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbi...The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃.展开更多
A corn-soybean meal diet （CSB） （or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM） （or Diet 2） wa...A corn-soybean meal diet （CSB） （or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM） （or Diet 2） was used as the basal diet, which was treated with four different treatments. Digestibility experiment was employed to discuss the collective effect of citric acid, and intrinsic and microbial phytase. By comparing and analyzing effects of them in the low-nutrient broiler diets, the results showed five treatments had similar effects on Tibia ash （%） （mg） （P〉0.05）. Under the supplementation of bacterial phytase or citric acid, the daily body weight gain （ADG）, gain：feed （G：F） ratio, and calcium （Ca） utilization were similar to that of standard-nutrient CSB diet （Diet 1） （P 〉 0.05）. And, fecal phosphorus （P） and CP utilization were lower than （P〈0.05） that of Diet 1. But P utilization was significantly higher than （P〈0.01） that of Diet 1. However, the ADG, G：F, and CP utilization produced by supplementation of intrinsic phytase were lower than those of Diet 1, but other aspects were similar to those produced by Diet 1 （P〉0.05）. In Diet 5, citric acid, intrinsic and bacterial phytase were added to the diet, which produced a 1.4% decrease on fecal P, a 7.2% increase on Ca utilization, which was significantly higher than （P〈0.01） those of the other four Diets, a 3.9% increase on G：F, which was similar to that of Diet 1, and a 2.3% increase on CP utilization, which was higher than （P〈0.05） that of the other three diets. In summary, the results of this study indicated that citric acid, intrinsic and bacterial phytase might have some additive or synergistic effects, and low-nutrient CSB diets with 15% wheat middlings, 750 U kg^-1 phytase, and 3% citric acid might substitute completely for standard CSB in broilers.展开更多
To evaluate the effect of different levels of citric acid (CA) combined with phytase and calcium levels in the diets of laying hens on the calcium and phosphorus (P) contents of eggs: yolk-albumen and shell, yolk colo...To evaluate the effect of different levels of citric acid (CA) combined with phytase and calcium levels in the diets of laying hens on the calcium and phosphorus (P) contents of eggs: yolk-albumen and shell, yolk color and egg quality. A study was conducted with 24-week-old laying hens fed with a diet based on sorghum and soybean meal with 2.7 Mcal of EM/kg, 15% crude protein, 3.25% calcium and 0.25% available P. The levels of CA, phytase and calcium were 0%, 0.6% and 1.2%;0 and 300 units of phytase (PHYU)/kg;and 3.0% and 3.25%, respectively. Phytase was added as an ingredient into to the diets, contributing 0.1% P and 0.3% calcium. A completely randomized factorial experiment was performed with a 3 × 2 × 2 design and 4 replications. The CA increased (P < 0.05) the P in the shell, and the combination of 1.2% CA, 300 PHYU phytase and 3.25% calcium increased (P < 0.05) the calcium in the eggshell. There was a CA × phytase × calcium interaction (P < 0.05) affecting egg yolk pigmentation;there were no differences in egg quality. It was concluded that adding CA to the diets of laying hens increases eggshell calcium content, and improves the phytase response. 1.2% CA × Phytase × 3.25% calcium significantly increases shell calcium by 0.56 g. Under the conditions of the present investigation, it would imply greater resistance of the eggs to be broken in the handling from the farm to the sales centers and consumer. Phytase interacts negatively with 0.6% CA at low calcium levels to degrade the yellow pigmentation of the yolk.展开更多
Trichloroethene （TCE） degradation by Fe（III）- activated calcium peroxide （CP） in the presence of citric acid （CA） in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced...Trichloroethene （TCE） degradation by Fe（III）- activated calcium peroxide （CP） in the presence of citric acid （CA） in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced TCE degradation significantly by increasing the concen- tration of soluble Fe（III） and promoting H202 generation. The generation of HO· and O2^-· in both the CP/Fe（III） and CP/Fe（III）/CA systems was confirmed with chemical probes. The results of radical scavenging tests showed that TCE degradation was due predominantly to direct oxidation by HO·, while O2^-· strengthened the generation of HO· by promoting Fe（III） transformation in the CP/Fe （III）/CA system. Acidic pH conditions were favorable for TCE degradation, and the TCE degradation rate decreased with increasing pH. The presence of Cl·-, HCO3·-, and humic acid （HA） inhibited TCE degradation to different extents for the CP/Fe（III）/CA system. Analysis of Cl·- production suggested that TCE degradation in the CP/Fe （III）/CA system occurred through a dechlorination process. In summary, this study provided detailed information for the application of CA-enhanced Fe（III）-activated calcium peroxide for treating TCE contaminated groundwater.展开更多
文摘The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃.
基金Shihezi University Natural Science Foundation, China （ZDGG200502）.
文摘A corn-soybean meal diet （CSB） （or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM） （or Diet 2） was used as the basal diet, which was treated with four different treatments. Digestibility experiment was employed to discuss the collective effect of citric acid, and intrinsic and microbial phytase. By comparing and analyzing effects of them in the low-nutrient broiler diets, the results showed five treatments had similar effects on Tibia ash （%） （mg） （P〉0.05）. Under the supplementation of bacterial phytase or citric acid, the daily body weight gain （ADG）, gain：feed （G：F） ratio, and calcium （Ca） utilization were similar to that of standard-nutrient CSB diet （Diet 1） （P 〉 0.05）. And, fecal phosphorus （P） and CP utilization were lower than （P〈0.05） that of Diet 1. But P utilization was significantly higher than （P〈0.01） that of Diet 1. However, the ADG, G：F, and CP utilization produced by supplementation of intrinsic phytase were lower than those of Diet 1, but other aspects were similar to those produced by Diet 1 （P〉0.05）. In Diet 5, citric acid, intrinsic and bacterial phytase were added to the diet, which produced a 1.4% decrease on fecal P, a 7.2% increase on Ca utilization, which was significantly higher than （P〈0.01） those of the other four Diets, a 3.9% increase on G：F, which was similar to that of Diet 1, and a 2.3% increase on CP utilization, which was higher than （P〈0.05） that of the other three diets. In summary, the results of this study indicated that citric acid, intrinsic and bacterial phytase might have some additive or synergistic effects, and low-nutrient CSB diets with 15% wheat middlings, 750 U kg^-1 phytase, and 3% citric acid might substitute completely for standard CSB in broilers.
文摘To evaluate the effect of different levels of citric acid (CA) combined with phytase and calcium levels in the diets of laying hens on the calcium and phosphorus (P) contents of eggs: yolk-albumen and shell, yolk color and egg quality. A study was conducted with 24-week-old laying hens fed with a diet based on sorghum and soybean meal with 2.7 Mcal of EM/kg, 15% crude protein, 3.25% calcium and 0.25% available P. The levels of CA, phytase and calcium were 0%, 0.6% and 1.2%;0 and 300 units of phytase (PHYU)/kg;and 3.0% and 3.25%, respectively. Phytase was added as an ingredient into to the diets, contributing 0.1% P and 0.3% calcium. A completely randomized factorial experiment was performed with a 3 × 2 × 2 design and 4 replications. The CA increased (P < 0.05) the P in the shell, and the combination of 1.2% CA, 300 PHYU phytase and 3.25% calcium increased (P < 0.05) the calcium in the eggshell. There was a CA × phytase × calcium interaction (P < 0.05) affecting egg yolk pigmentation;there were no differences in egg quality. It was concluded that adding CA to the diets of laying hens increases eggshell calcium content, and improves the phytase response. 1.2% CA × Phytase × 3.25% calcium significantly increases shell calcium by 0.56 g. Under the conditions of the present investigation, it would imply greater resistance of the eggs to be broken in the handling from the farm to the sales centers and consumer. Phytase interacts negatively with 0.6% CA at low calcium levels to degrade the yellow pigmentation of the yolk.
基金This study was financially supported by the National Natural Science Foundation of China （Grant Nos. 41373094 and 51208199）, China Postdoctoral Science Foundation （No. 2015M570341） and the Fundamental Research Funds for the Central Universities （No. 22A2015 14057）. The contributions of Dr. Mark Brusseau were supported by the NIEHS Superfund Research Program （P42 ES04940）.
文摘Trichloroethene （TCE） degradation by Fe（III）- activated calcium peroxide （CP） in the presence of citric acid （CA） in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced TCE degradation significantly by increasing the concen- tration of soluble Fe（III） and promoting H202 generation. The generation of HO· and O2^-· in both the CP/Fe（III） and CP/Fe（III）/CA systems was confirmed with chemical probes. The results of radical scavenging tests showed that TCE degradation was due predominantly to direct oxidation by HO·, while O2^-· strengthened the generation of HO· by promoting Fe（III） transformation in the CP/Fe （III）/CA system. Acidic pH conditions were favorable for TCE degradation, and the TCE degradation rate decreased with increasing pH. The presence of Cl·-, HCO3·-, and humic acid （HA） inhibited TCE degradation to different extents for the CP/Fe（III）/CA system. Analysis of Cl·- production suggested that TCE degradation in the CP/Fe （III）/CA system occurred through a dechlorination process. In summary, this study provided detailed information for the application of CA-enhanced Fe（III）-activated calcium peroxide for treating TCE contaminated groundwater.
