The aim of the present study is to investigate the effects of Monascus fermentation on the aroma pattern of semi-dried grass carp. Semi-dried fish was fermented using Monascus purpureus GDMCC3.439. The volatile flavor...The aim of the present study is to investigate the effects of Monascus fermentation on the aroma pattern of semi-dried grass carp. Semi-dried fish was fermented using Monascus purpureus GDMCC3.439. The volatile flavor substances present in fresh fish, semi-dry fish and Monascus fermented semi-dried fish were compared by simultaneous distillation and extraction combined with gas chromatograph-mass spectrometer (GC-MS). The results showed that alcohols, aldehydes and ketones were the main components of the flavor of the unfermented and fermented semi-dried grass crap. Monascus fermentation could significantly affect the volatile flavor substances of semi-dried grass carp. Moreover, the processing of semi-dried fish fermented by Monascus could not only effectively improve the fishy smell of fresh fish, but also make up for the defect of the pickled flavor of semi-dried fish. Eighteen of the main volatile components in semi-dried fish fermented by Monascus were identified by relative odor activity value (ROAV), as follows: 1-octene-3-ol, phenylethanol, hexanal, heptanal, nonanal, (E)-2-octenal, 3-Methyl-1-butanal, benzaldehyde, (E)-2-nonenal, (E,E)-2,4-heptadienal, (E)-2-Decenal, phenylacetaldehyde, (E,E)-2.4-decadienal, tetradecanal, 2,3-butanone, 2,3-octanedione, alpha-pinene, 2-pentane furan.展开更多
Despite its low water activity (Aw), food poisoning accidents associated with beef jerky consumption and problems due to mold growth have been reported. The objects of this study were to investigate the effect of yuza...Despite its low water activity (Aw), food poisoning accidents associated with beef jerky consumption and problems due to mold growth have been reported. The objects of this study were to investigate the effect of yuza powder and the mixture of sodium lactate (SL) and sodium acetate (SA) to prevent the growth of S. aureus and A. flavus, as well as aflatoxin production in beef jerky. Different concentrations of the SL and SA (0, 0.75, and 1%) mixture were added to sliced beef and the Aws were adjusted to 0.70, 0.75, and 0.80. The effect of yuza powder and the SL and SA mixture on S. aureus in beef jerky (Aw 0.80) was also investigated at 10°C and 25°C. A rapid decline is that S. aureus population was observed in beef jerky containing yuza powder and mixtures of SL and SA. Antifungal effects against A. flavus were observed in beef jerky containing the SL and SA mixture at Aw below 0.75. The growth of A. flavus and aflatoxin production were prevented in beef jerky containing the yuza powder and a 1% mixture of SL and SA at 10°C and 0.80 Aw. The addition of yuza powder increased the hardness score of the beef jerky. Under current Aw regulations (0.80), beef jerky may pose a public health risk due to the growth of A. flavus and the presence of aflatoxin.展开更多
To test the feasibility of radiant energy vacuum (REV) dehydration, a technology that couples microwave cooking with vacuum pressure, on beef jerky preparation, the physical and microbial properties of the final jer...To test the feasibility of radiant energy vacuum (REV) dehydration, a technology that couples microwave cooking with vacuum pressure, on beef jerky preparation, the physical and microbial properties of the final jerky product was compared to conventional preparation methods. Physical characteristics assessed using puncture and shear tests of samples prepared using REV dehydration compared to the traditional method were not statistically different (P 〈 0.05). Moisture content and water activity levels were also very similar between the two products, To test microbiological quality, samples were homogenized in a stomacher and a variety of 3 M Petrifilms were used to evaluate the microbial load. Raw beef harboured low numbers of microbes, but the post-marination pasteurization/smoking step used in both treatments eliminated all culturable microorganisms tested for. To further investigate the ability of REV dehydration to kill microbes, samples were spiked with Listeria innocua after the pasteurization/smoking step but prior to REV dehydration. Samples were taken at different time intervals for microbial enumeration, and a decimal reduction time of 1 min was calculated, with 99.99% of 1.98 × 10^7 CFU g^-1 Listeria being killed in five min. Improved drying times were observed for jerky samples prepared using the REV method offering potential energy savings during jerky preparation.展开更多
The third order explicit autonomous differential equations named as jerk equations represent an interesting subclass of dynamical systems that can exhibit many major features of the regular and chaotic motion. In this...The third order explicit autonomous differential equations named as jerk equations represent an interesting subclass of dynamical systems that can exhibit many major features of the regular and chaotic motion. In this paper, we show that an algebraically simple system, the Genesio system can be recast into a jerky dynamics and its jerk equation can be derived from one-dimensional Newtonian equation. We also investigate the global dynamical properties of the corresponding jerk system.展开更多
High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and qualit...High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and quality characteristics of the flour.Although rice flour obtained through mainstream wet milling methods exhibits superior quality,low production efficiency and wastewater discharge limit the development of the industry.Dry milling,on the other hand,conserves water resources,but adversely affects flour performance due to excessive heat generation.As an emerging powder-making technique,semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact.This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels.However,continuous production remains a challenge.This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities.It also discusses key control indicators and technical considerations for rice flour processing equipment and processes.展开更多
文摘The aim of the present study is to investigate the effects of Monascus fermentation on the aroma pattern of semi-dried grass carp. Semi-dried fish was fermented using Monascus purpureus GDMCC3.439. The volatile flavor substances present in fresh fish, semi-dry fish and Monascus fermented semi-dried fish were compared by simultaneous distillation and extraction combined with gas chromatograph-mass spectrometer (GC-MS). The results showed that alcohols, aldehydes and ketones were the main components of the flavor of the unfermented and fermented semi-dried grass crap. Monascus fermentation could significantly affect the volatile flavor substances of semi-dried grass carp. Moreover, the processing of semi-dried fish fermented by Monascus could not only effectively improve the fishy smell of fresh fish, but also make up for the defect of the pickled flavor of semi-dried fish. Eighteen of the main volatile components in semi-dried fish fermented by Monascus were identified by relative odor activity value (ROAV), as follows: 1-octene-3-ol, phenylethanol, hexanal, heptanal, nonanal, (E)-2-octenal, 3-Methyl-1-butanal, benzaldehyde, (E)-2-nonenal, (E,E)-2,4-heptadienal, (E)-2-Decenal, phenylacetaldehyde, (E,E)-2.4-decadienal, tetradecanal, 2,3-butanone, 2,3-octanedione, alpha-pinene, 2-pentane furan.
文摘Despite its low water activity (Aw), food poisoning accidents associated with beef jerky consumption and problems due to mold growth have been reported. The objects of this study were to investigate the effect of yuza powder and the mixture of sodium lactate (SL) and sodium acetate (SA) to prevent the growth of S. aureus and A. flavus, as well as aflatoxin production in beef jerky. Different concentrations of the SL and SA (0, 0.75, and 1%) mixture were added to sliced beef and the Aws were adjusted to 0.70, 0.75, and 0.80. The effect of yuza powder and the SL and SA mixture on S. aureus in beef jerky (Aw 0.80) was also investigated at 10°C and 25°C. A rapid decline is that S. aureus population was observed in beef jerky containing yuza powder and mixtures of SL and SA. Antifungal effects against A. flavus were observed in beef jerky containing the SL and SA mixture at Aw below 0.75. The growth of A. flavus and aflatoxin production were prevented in beef jerky containing the yuza powder and a 1% mixture of SL and SA at 10°C and 0.80 Aw. The addition of yuza powder increased the hardness score of the beef jerky. Under current Aw regulations (0.80), beef jerky may pose a public health risk due to the growth of A. flavus and the presence of aflatoxin.
文摘To test the feasibility of radiant energy vacuum (REV) dehydration, a technology that couples microwave cooking with vacuum pressure, on beef jerky preparation, the physical and microbial properties of the final jerky product was compared to conventional preparation methods. Physical characteristics assessed using puncture and shear tests of samples prepared using REV dehydration compared to the traditional method were not statistically different (P 〈 0.05). Moisture content and water activity levels were also very similar between the two products, To test microbiological quality, samples were homogenized in a stomacher and a variety of 3 M Petrifilms were used to evaluate the microbial load. Raw beef harboured low numbers of microbes, but the post-marination pasteurization/smoking step used in both treatments eliminated all culturable microorganisms tested for. To further investigate the ability of REV dehydration to kill microbes, samples were spiked with Listeria innocua after the pasteurization/smoking step but prior to REV dehydration. Samples were taken at different time intervals for microbial enumeration, and a decimal reduction time of 1 min was calculated, with 99.99% of 1.98 × 10^7 CFU g^-1 Listeria being killed in five min. Improved drying times were observed for jerky samples prepared using the REV method offering potential energy savings during jerky preparation.
文摘The third order explicit autonomous differential equations named as jerk equations represent an interesting subclass of dynamical systems that can exhibit many major features of the regular and chaotic motion. In this paper, we show that an algebraically simple system, the Genesio system can be recast into a jerky dynamics and its jerk equation can be derived from one-dimensional Newtonian equation. We also investigate the global dynamical properties of the corresponding jerk system.
基金supported by the National Natural Science Foundation of China(Grant No.31972005)Xinjiang Uygur Autonomous Region‘Tianshan Talent’Training Plan Project,China(Grant No.2022TSYCCX0063).
文摘High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and quality characteristics of the flour.Although rice flour obtained through mainstream wet milling methods exhibits superior quality,low production efficiency and wastewater discharge limit the development of the industry.Dry milling,on the other hand,conserves water resources,but adversely affects flour performance due to excessive heat generation.As an emerging powder-making technique,semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact.This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels.However,continuous production remains a challenge.This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities.It also discusses key control indicators and technical considerations for rice flour processing equipment and processes.