[Objective] The aim was to investigate the effects of different drying temperatures on the physiochemical properties and antioxidant activity of balsam pear slices. [Method] Balsam pear slices were dried at different ...[Objective] The aim was to investigate the effects of different drying temperatures on the physiochemical properties and antioxidant activity of balsam pear slices. [Method] Balsam pear slices were dried at different hot air temperatures, 40, 50, 60, 70 and 80 ℃. [Result] The polyphenols content was highest （2.83 mg/g） in the balsam pear slices dried at 50 ℃, and the flavonoids content was highest （2.584 mg/g） in those dried at 60 ℃. Different drying temperatures had a great impact on the antioxidant capacity of polyphenols in balsam pear. The balsam pear slices dried at 50 ℃ showed the strongest capacity for scavenging DPPH free radicals with IC50 of 0.015 mg/ml, and those dried at 80 ℃ showed the strongest capacity for removing ABTS free radicals with IC50 of 0.0689 mg/ml. [Conclusion] The hot air temperature of 50 ℃ had the least impact on the quality of balsam pear slices.展开更多
Drying is a basic link in seafood processing, and the effects of forced air drying and vacuum drying on the effective components of Stichopus japonicus viscera were compared with the moisture, total saponin and polysa...Drying is a basic link in seafood processing, and the effects of forced air drying and vacuum drying on the effective components of Stichopus japonicus viscera were compared with the moisture, total saponin and polysaccharide contents as the detection indexes. The contents of effective components obtained using forced air drying were slightly lower than those obtained using vacuum drying, but the forced air drying method used short drying time and low economic energy consumption. Excellent drying effects and low cost of forced air drying made it can be adapted to the requirements of large-scale production applications.展开更多
The combined microwave-convective drying is a novel drying method and has many advantages, such as swift drying, equable drying and sterilization. This paper studies the drying characteristic of medical pill in microw...The combined microwave-convective drying is a novel drying method and has many advantages, such as swift drying, equable drying and sterilization. This paper studies the drying characteristic of medical pill in microwave-convective drying process. The influential parameters of pill drying characteristics including pill size, quality, air velocity, temperature and the input power of microwave, are experimentally investigated. Results show that the drying process is influenced by the intrinsic heat of microwave power, and the environment and the resistance of mass transfer. It has the advantage of the microwave-convective drying in saving energy, reducing labor intensity and sterilizing. The method with the high efficiency is suitable for pharmacy industry.展开更多
Spin flash dryer has the advantages of both fluidized bed dryer and pneumatic dryer.It has predominance in dealing with thermal sensitive materials.In this paper,the distribution of the air velocity in the spin flash ...Spin flash dryer has the advantages of both fluidized bed dryer and pneumatic dryer.It has predominance in dealing with thermal sensitive materials.In this paper,the distribution of the air velocity in the spin flash dryer is discussed,which indicates that the rotating air in the dryer chamber can be divided into two areas,potential flow area and plane swirl area.Experiments show that air tangent velocity effects the process of granulation most remarkably.The radial distribution and moisture content of the particles have their intrinsic rules along either the diameter or height of the drying chamber.Besides,the operating parameters of predrying on bleaching powder are optimized.To meet the strict standard of the wet pressing granulator on the moisture content of the feeder,a narrow lap is made at proper height in the wall of the drying chamber,where a chute and a rotating valve are installed in order to predry the filter cake and remove a part of water.Then the material is fed into the wet pressing granulator.展开更多
The heating area of the material is large and the thermal efficiency is high,but it is n ecessary to control the suitable drying temperature ofdiffere nt medici nal materials to preserve the effective in gredients.D i...The heating area of the material is large and the thermal efficiency is high,but it is n ecessary to control the suitable drying temperature ofdiffere nt medici nal materials to preserve the effective in gredients.D iff ere nt kinds of Chinese medicine need different drying conditions to fulfill good drying requirements.Natural drying in the shade is one of the traditional drying methods,which takes a long time and is easily affected by the weather.The water volatilizes slowly.It is prone to mildew and discoloration during the drying process.However,it can better preserve the volatile oil components of Chinese medicine.The hot-air drying machine has lower requirements.The medicinal materials have a large heating area and high thermal efficiency,but it is necessary to control the appropriate drying temperature of different medicinal materials in order to preserve the active ingredients of the medicinal materials;it is not suitable for medicinal materials that stick and bind easily.The microwave drying method possesses superiority in drying some valuable medicinal materials such as Ren she n(Radix et Rhizoma Ginseng)and Lurong(Co「nu Cervi Pantotrichum),and the effective ingredients are preserved at a high degree;it can also achieve the purpose of killing enzymes and protecting glycosides and have a good bactericidal effect,but it is not suitable for Chinese medicines containing heat-sensitive ingredients,because it will destroy most of the proteins,amino acids,and peptides of Chinese medicine and result in the loss of efficacy.The far-infrared drying method is suitable for drying thin-layer medicinal materials and is friendly to the environment.Freeze-drying can preserve the active ingredients very well and greatly retain the efficacy,but it has obvious limitations in preserving some Chinese medicinal materials that need to kill enzymes and protect glycosides;besides,the cost is relatively high and the drying time is long.展开更多
Drying of sugar cane bagasse was theoretically and experimentally studied ina cyclone. The experiments were carried out using hot air as drying agent. The influence of thecyclone conical part was studied. It was shown...Drying of sugar cane bagasse was theoretically and experimentally studied ina cyclone. The experiments were carried out using hot air as drying agent. The influence of thecyclone conical part was studied. It was shown that the conical part has a great influence on theparticle residence time and, consequently, on moisture reduction. Experimental results were alikeindustrial ones. CFX 4.4 from AEA Technology was used to simulate some experiments. Simulated andexperimental results were close and showed that the presented model leads to a good prediction.展开更多
Drying is essential for the production of fibre after retting process. Flax fibre was subjected to microwave drying at controlled temperatures to study the change in drying rate and qualities. The rate of drying was t...Drying is essential for the production of fibre after retting process. Flax fibre was subjected to microwave drying at controlled temperatures to study the change in drying rate and qualities. The rate of drying was then compared with conventional hot air drying. The product temperature was maintained at 40 ℃, 60 ℃or 80 ℃ for both microwave and hot air drying. The initial moisture content of flax fibre was about 60% （wet basis）. The microwave drying was conducted in a microwave apparatus which recorded mass, product temperature, incident microwave power, reflected microwave power and inlet/outlet air temperature. The final moisture content was set to 9% （wet basis）. Microwave-convective drying ensured about 30% to 70% reduction of drying time for drying flax fibre as compared to hot air drying. Curve fitting with different mathematical models were carried out. While a significant difference in colorimeter-assessed co/our existed between microwave-convective dried flax fibre and hot air dried flax fibre. The tensile strength of flax fibre, measured with an Instron apparatus, increased with an increase in the processing temperature of both processes. Hot air dried flax fibre showed the greatest tensile strength and modulus of elasticity at processing temperatures of 60 ℃ and 80 ℃.展开更多
[Objective]To explore the best T.sinensis processing technology.[Method]The T.sinensis was treated by hot wind drying,freeze drying and blanching,and the contents of ascorbic acid,total phenolics and nitrite were dete...[Objective]To explore the best T.sinensis processing technology.[Method]The T.sinensis was treated by hot wind drying,freeze drying and blanching,and the contents of ascorbic acid,total phenolics and nitrite were determined respectively before and after the treatment to be a standard to evaluate the influence of different processing methods on the quality of T.sinensis.[Result]Both drying and blanching produced certain impact on the contents of all three components,among which the content of ascorbic acid was slightly influenced by vacuum freeze drying and short-time blanching,but greatly affected by long-time blanching and hot wind drying;the loss rate of polyphenols was above 60% when the hot wind drying,freeze drying and blanching lasted for more than 5 min,while it experienced little change under short-time blanching;hot wind drying and blanching may greatly reduce the content of nitrite,however,the vacuum freeze drying even improved the content,which would produce adverse impact on food safety.[Conclusion]Short-time blanching is the best method to process T.sinensis,it can effectively reduce its content of nitrite and retain the nutrients.展开更多
文摘[Objective] The aim was to investigate the effects of different drying temperatures on the physiochemical properties and antioxidant activity of balsam pear slices. [Method] Balsam pear slices were dried at different hot air temperatures, 40, 50, 60, 70 and 80 ℃. [Result] The polyphenols content was highest （2.83 mg/g） in the balsam pear slices dried at 50 ℃, and the flavonoids content was highest （2.584 mg/g） in those dried at 60 ℃. Different drying temperatures had a great impact on the antioxidant capacity of polyphenols in balsam pear. The balsam pear slices dried at 50 ℃ showed the strongest capacity for scavenging DPPH free radicals with IC50 of 0.015 mg/ml, and those dried at 80 ℃ showed the strongest capacity for removing ABTS free radicals with IC50 of 0.0689 mg/ml. [Conclusion] The hot air temperature of 50 ℃ had the least impact on the quality of balsam pear slices.
文摘Drying is a basic link in seafood processing, and the effects of forced air drying and vacuum drying on the effective components of Stichopus japonicus viscera were compared with the moisture, total saponin and polysaccharide contents as the detection indexes. The contents of effective components obtained using forced air drying were slightly lower than those obtained using vacuum drying, but the forced air drying method used short drying time and low economic energy consumption. Excellent drying effects and low cost of forced air drying made it can be adapted to the requirements of large-scale production applications.
文摘The combined microwave-convective drying is a novel drying method and has many advantages, such as swift drying, equable drying and sterilization. This paper studies the drying characteristic of medical pill in microwave-convective drying process. The influential parameters of pill drying characteristics including pill size, quality, air velocity, temperature and the input power of microwave, are experimentally investigated. Results show that the drying process is influenced by the intrinsic heat of microwave power, and the environment and the resistance of mass transfer. It has the advantage of the microwave-convective drying in saving energy, reducing labor intensity and sterilizing. The method with the high efficiency is suitable for pharmacy industry.
文摘Spin flash dryer has the advantages of both fluidized bed dryer and pneumatic dryer.It has predominance in dealing with thermal sensitive materials.In this paper,the distribution of the air velocity in the spin flash dryer is discussed,which indicates that the rotating air in the dryer chamber can be divided into two areas,potential flow area and plane swirl area.Experiments show that air tangent velocity effects the process of granulation most remarkably.The radial distribution and moisture content of the particles have their intrinsic rules along either the diameter or height of the drying chamber.Besides,the operating parameters of predrying on bleaching powder are optimized.To meet the strict standard of the wet pressing granulator on the moisture content of the feeder,a narrow lap is made at proper height in the wall of the drying chamber,where a chute and a rotating valve are installed in order to predry the filter cake and remove a part of water.Then the material is fed into the wet pressing granulator.
文摘The heating area of the material is large and the thermal efficiency is high,but it is n ecessary to control the suitable drying temperature ofdiffere nt medici nal materials to preserve the effective in gredients.D iff ere nt kinds of Chinese medicine need different drying conditions to fulfill good drying requirements.Natural drying in the shade is one of the traditional drying methods,which takes a long time and is easily affected by the weather.The water volatilizes slowly.It is prone to mildew and discoloration during the drying process.However,it can better preserve the volatile oil components of Chinese medicine.The hot-air drying machine has lower requirements.The medicinal materials have a large heating area and high thermal efficiency,but it is necessary to control the appropriate drying temperature of different medicinal materials in order to preserve the active ingredients of the medicinal materials;it is not suitable for medicinal materials that stick and bind easily.The microwave drying method possesses superiority in drying some valuable medicinal materials such as Ren she n(Radix et Rhizoma Ginseng)and Lurong(Co「nu Cervi Pantotrichum),and the effective ingredients are preserved at a high degree;it can also achieve the purpose of killing enzymes and protecting glycosides and have a good bactericidal effect,but it is not suitable for Chinese medicines containing heat-sensitive ingredients,because it will destroy most of the proteins,amino acids,and peptides of Chinese medicine and result in the loss of efficacy.The far-infrared drying method is suitable for drying thin-layer medicinal materials and is friendly to the environment.Freeze-drying can preserve the active ingredients very well and greatly retain the efficacy,but it has obvious limitations in preserving some Chinese medicinal materials that need to kill enzymes and protect glycosides;besides,the cost is relatively high and the drying time is long.
文摘Drying of sugar cane bagasse was theoretically and experimentally studied ina cyclone. The experiments were carried out using hot air as drying agent. The influence of thecyclone conical part was studied. It was shown that the conical part has a great influence on theparticle residence time and, consequently, on moisture reduction. Experimental results were alikeindustrial ones. CFX 4.4 from AEA Technology was used to simulate some experiments. Simulated andexperimental results were close and showed that the presented model leads to a good prediction.
文摘Drying is essential for the production of fibre after retting process. Flax fibre was subjected to microwave drying at controlled temperatures to study the change in drying rate and qualities. The rate of drying was then compared with conventional hot air drying. The product temperature was maintained at 40 ℃, 60 ℃or 80 ℃ for both microwave and hot air drying. The initial moisture content of flax fibre was about 60% （wet basis）. The microwave drying was conducted in a microwave apparatus which recorded mass, product temperature, incident microwave power, reflected microwave power and inlet/outlet air temperature. The final moisture content was set to 9% （wet basis）. Microwave-convective drying ensured about 30% to 70% reduction of drying time for drying flax fibre as compared to hot air drying. Curve fitting with different mathematical models were carried out. While a significant difference in colorimeter-assessed co/our existed between microwave-convective dried flax fibre and hot air dried flax fibre. The tensile strength of flax fibre, measured with an Instron apparatus, increased with an increase in the processing temperature of both processes. Hot air dried flax fibre showed the greatest tensile strength and modulus of elasticity at processing temperatures of 60 ℃ and 80 ℃.
基金Supported by National Natural Science Foundation(30771510)
文摘[Objective]To explore the best T.sinensis processing technology.[Method]The T.sinensis was treated by hot wind drying,freeze drying and blanching,and the contents of ascorbic acid,total phenolics and nitrite were determined respectively before and after the treatment to be a standard to evaluate the influence of different processing methods on the quality of T.sinensis.[Result]Both drying and blanching produced certain impact on the contents of all three components,among which the content of ascorbic acid was slightly influenced by vacuum freeze drying and short-time blanching,but greatly affected by long-time blanching and hot wind drying;the loss rate of polyphenols was above 60% when the hot wind drying,freeze drying and blanching lasted for more than 5 min,while it experienced little change under short-time blanching;hot wind drying and blanching may greatly reduce the content of nitrite,however,the vacuum freeze drying even improved the content,which would produce adverse impact on food safety.[Conclusion]Short-time blanching is the best method to process T.sinensis,it can effectively reduce its content of nitrite and retain the nutrients.
