The effects of frying oil temperature (FOT) and time on densities and shrinkage in chicken breast meat during deep-fat frying were investigated. De-boned Chicken breast samples were diced and fried at different FOT (...The effects of frying oil temperature (FOT) and time on densities and shrinkage in chicken breast meat during deep-fat frying were investigated. De-boned Chicken breast samples were diced and fried at different FOT (170℃, 180℃, and 190℃) in an industrial fryer for periods varying from 5 to 900 s. Bulk and apparent densities were determined with a fluid displacement pycnometer, and fat analysis was conducted using soxhlet extraction with petroleum ether solvent. The physical structure of chicken meat changed significantly with the frying time and FOT (P < 0.001). Bulk density was 1.15 g/cm<sup>3</sup> in the raw product and decreased to 0.98, 0.95, and 0.93 g/cm<sup>3</sup> after 900 s of deep-frying at 170℃, 180℃ and 190℃, respectively. Similarly, apparent density changed from 1.13 to 1.25, 1.24 and 1.22 g/cm<sup>3</sup> and moisture loss was linearly correlated with both densities. Volumetric shrinkage was significantly (P < 0.05) affected by the process variables and hence a linear correlation also existed with moisture loss. The rates of shrinkage were 0.013, 0.001, and 0.008/s and occurred rapidly during the first 90s of FOT (170℃, 180℃, and 190℃), respectively and decreased as frying time increased.展开更多
Response surface methodology involving historical data design has been successfully developed with the aim of predicting optimum operating conditions for dodo fried from plantain. Frying temperature and time were 150,...Response surface methodology involving historical data design has been successfully developed with the aim of predicting optimum operating conditions for dodo fried from plantain. Frying temperature and time were 150, 160, 170, 180 and 190°C and 2.0, 2.5, 3.0, 3.5 and 4.0 min respectively. The parameters analyzed included moisture content, oil content, texture and change in colour. The fitted functions were optimized for moisture content, oil content, texture and change in colour in order to obtain a product with the acceptable quality attributes. Frying conditions had significant (p R<sup>2</sup>) of the generated models ranged from 0.91 to 0.99. Optimum frying condition was 177.51°C for 2.10 min. This gave 14.16% moisture content, 1.54% oil content, 2.93 N texture and 40.89 change in colour. Desirability of 0.7 was obtained for optimum conditions. Therefore, the estimated response surface model can be used to optimize the frying process of dodo fried from plantain.展开更多
The flavor is a decisive sensory characteristic that determines the popularity of French fries(FFs).During high-oleic rapeseed oil(RO)frying,the flavor development of FFs showed three noticeable stages including break...The flavor is a decisive sensory characteristic that determines the popularity of French fries(FFs).During high-oleic rapeseed oil(RO)frying,the flavor development of FFs showed three noticeable stages including break-in(3.5%-7.5%of total polar compounds(TPC)),optimum(7.5%-22.18%of TPC),and degrading stages(above 22.18%of TPC).Further,in order to distinguish the key aroma compounds in each stage,the FFs prepared in RO at TPC of 3.5%(FF4),14.5%(FF15),and 26.96%(FF27)and their relevant oils(RO4,RO15,RO27)were selected for sensory-directed analysis.The results revealed that the FF4 had low contents of(E,E)-2,4-decadienal(deep-fried odor)which also caused lower sensory score in FF4 sample.The higher contents of(E,E)-2,4-decadienal in FF15 induced its higher deep-fried odor.The FF27 had higher hexanoic acid(sweaty odor),heptanoic acid,nonanoic acid,benzene acetaldehyde(stale odor),and trans-4,5-epoxy-(E)-2-decenal(metallic odor)compared with FF4 and FF15,thus leading to the undesirable flavor of FF27.Moreover,the decrease of 2,5-dimethylpyrazine and 2-ethyl-6-methyl-pyrazine in FF27 induced the lower roasty flavor,which may also lead to the decline of the sensory score.Similarly,the higher contents of(E)-2-undecenal,hexanoic acid,heptanoic acid,and nonanoic acid in RO27 lead to increase its rancid score and thus lower the sensory score.展开更多
Charles C.Fries是被语料库语言学界遗忘的一位重量级人物。他既是美国结构主义的代表人物,同时也是一位具有超前意识的语料库语言学思想家和杰出实践者。他的一些语料库语言学思想及方法至今对语料库语言学仍具有指导意义。对其主要的...Charles C.Fries是被语料库语言学界遗忘的一位重量级人物。他既是美国结构主义的代表人物,同时也是一位具有超前意识的语料库语言学思想家和杰出实践者。他的一些语料库语言学思想及方法至今对语料库语言学仍具有指导意义。对其主要的语料库语言学思想及方法:真实客观的数据观、将语言对比特征作为研究的焦点以及实证的研究范式,进行了评述,并在最后指出其思想和方法上的一些缺陷。展开更多
Charles C.Fries的贡献不仅在语言教育上,他的语言学理论在当时也独树一帜。讨论并分析了Fries的相关语篇分析思想。研究发现,Fries的语境观与Malinowski和同时期J.R.Firth的语境观大同小异。Fries的序列信号显示了他对话语衔接和连贯...Charles C.Fries的贡献不仅在语言教育上,他的语言学理论在当时也独树一帜。讨论并分析了Fries的相关语篇分析思想。研究发现,Fries的语境观与Malinowski和同时期J.R.Firth的语境观大同小异。Fries的序列信号显示了他对话语衔接和连贯的看法,他的这些语篇分析思想对后来的超句子研究有着一定积极影响。有必要重新审视和评价Charles C.Fries对结构语言学的贡献。展开更多
文摘The effects of frying oil temperature (FOT) and time on densities and shrinkage in chicken breast meat during deep-fat frying were investigated. De-boned Chicken breast samples were diced and fried at different FOT (170℃, 180℃, and 190℃) in an industrial fryer for periods varying from 5 to 900 s. Bulk and apparent densities were determined with a fluid displacement pycnometer, and fat analysis was conducted using soxhlet extraction with petroleum ether solvent. The physical structure of chicken meat changed significantly with the frying time and FOT (P < 0.001). Bulk density was 1.15 g/cm<sup>3</sup> in the raw product and decreased to 0.98, 0.95, and 0.93 g/cm<sup>3</sup> after 900 s of deep-frying at 170℃, 180℃ and 190℃, respectively. Similarly, apparent density changed from 1.13 to 1.25, 1.24 and 1.22 g/cm<sup>3</sup> and moisture loss was linearly correlated with both densities. Volumetric shrinkage was significantly (P < 0.05) affected by the process variables and hence a linear correlation also existed with moisture loss. The rates of shrinkage were 0.013, 0.001, and 0.008/s and occurred rapidly during the first 90s of FOT (170℃, 180℃, and 190℃), respectively and decreased as frying time increased.
文摘Response surface methodology involving historical data design has been successfully developed with the aim of predicting optimum operating conditions for dodo fried from plantain. Frying temperature and time were 150, 160, 170, 180 and 190°C and 2.0, 2.5, 3.0, 3.5 and 4.0 min respectively. The parameters analyzed included moisture content, oil content, texture and change in colour. The fitted functions were optimized for moisture content, oil content, texture and change in colour in order to obtain a product with the acceptable quality attributes. Frying conditions had significant (p R<sup>2</sup>) of the generated models ranged from 0.91 to 0.99. Optimum frying condition was 177.51°C for 2.10 min. This gave 14.16% moisture content, 1.54% oil content, 2.93 N texture and 40.89 change in colour. Desirability of 0.7 was obtained for optimum conditions. Therefore, the estimated response surface model can be used to optimize the frying process of dodo fried from plantain.
基金financially supported by the National First-Class Discipline Program of Food Science and Technology (JUFSTR20180202)Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX20_1852)+1 种基金National Natural Science Foundation of China (31901728)Jiangsu Planned Projects for Postdoctoral Research Funds (2020Z297)
文摘The flavor is a decisive sensory characteristic that determines the popularity of French fries(FFs).During high-oleic rapeseed oil(RO)frying,the flavor development of FFs showed three noticeable stages including break-in(3.5%-7.5%of total polar compounds(TPC)),optimum(7.5%-22.18%of TPC),and degrading stages(above 22.18%of TPC).Further,in order to distinguish the key aroma compounds in each stage,the FFs prepared in RO at TPC of 3.5%(FF4),14.5%(FF15),and 26.96%(FF27)and their relevant oils(RO4,RO15,RO27)were selected for sensory-directed analysis.The results revealed that the FF4 had low contents of(E,E)-2,4-decadienal(deep-fried odor)which also caused lower sensory score in FF4 sample.The higher contents of(E,E)-2,4-decadienal in FF15 induced its higher deep-fried odor.The FF27 had higher hexanoic acid(sweaty odor),heptanoic acid,nonanoic acid,benzene acetaldehyde(stale odor),and trans-4,5-epoxy-(E)-2-decenal(metallic odor)compared with FF4 and FF15,thus leading to the undesirable flavor of FF27.Moreover,the decrease of 2,5-dimethylpyrazine and 2-ethyl-6-methyl-pyrazine in FF27 induced the lower roasty flavor,which may also lead to the decline of the sensory score.Similarly,the higher contents of(E)-2-undecenal,hexanoic acid,heptanoic acid,and nonanoic acid in RO27 lead to increase its rancid score and thus lower the sensory score.
