Decomposition kinetics of gaseous ozone in peanuts

Alencar, Ernandes Rodrigues de; Faroni, L. R. D.; Martins, Márcio Arêdes; Costa, A. R. da; Cecon, Paulo R.

doi:10.1590/s0100-69162011000500011

Cited by 30 publications

(34 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Nesse sentido, tem-se que a degradação do ozônio ocorre, ao longo da coluna, mesmo que em taxa reduzida (STRAIT, 1998), influenciando, dessa forma, a concentração residual na saída do sistema. Outros fatores podem influenciar o processo de saturação, tais como umidade do produto, temperatura e vazão do gás (ALENCAR et al, 2011a).…”

Section: Resultsunclassified

Saturação do ozônio em coluna contendo grãos de amendoim e efeito na qualidade

Roberto

Alencar

Ferreira

et al. 2016

Braz. J. Food Technol.

View full text Add to dashboard Cite

Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribution, que permite uso, distribuição e reprodução em qualquer meio, sem restrições desde que o trabalho original seja corretamente citado. Saturação do ozônio em coluna contendo grãos de amendoim e efeito na qualidade Ozone saturation in a column containing peanut kernels and the effect on quality ResumoObjetivou-se com este trabalho avaliar o processo de saturação do ozônio em coluna contendo amendoim e o efeito na qualidade de produto. Utilizaram-se grãos com teor de umidade em torno de 6,8% (b.u.), acondicionados em recipientes cilíndricos de PVC, com 1,10 m de altura e 15 cm de diâmetro. O gás, nas concentrações de 1,59 e 2,78 mg L -1 , foi injetado na base da coluna e os valores adotados de altura da coluna de grãos foram de 0,25, 0,50 e 0,75 m. Determinaram-se os tempos e as concentrações de saturação e avaliou-se a qualidade dos grãos ozonizados. Para os grãos ozonizados na concentração de 1,59 mg L -1 , obteve-se tempo de saturação na faixa entre 222 e 449 min. No que tange à relação C Sat /C 0 , obtiveram-se valores entre 0,32 e 0,48. Com relação aos grãos submetidos à ozonização na concentração de 2,78 mg L -1 , obteve-se tempo de saturação na faixa entre 78 e 251 min. No que se refere à relação C Sat /C 0 , para a concentração inicial de 2,78 mg L -1 , os valores permaneceram entre 0,46 e 0,81. É possível concluir, a partir dos resultados obtidos, que, à medida que se aumenta a altura da coluna de grãos de amendoim, há aumento do tempo de saturação e decréscimo da concentração de saturação. Não houve alteração na qualidade do produto durante o processo de ozonização. Palavras-chave:Ozonização; Saturação; Alteração qualitativa. SummaryThe objective of this study was to evaluate the ozone saturation process in a column containing peanuts and the effect on product quality. Peanuts with a moisture content of about 6.8% (w.b.) were used, packed in cylindrical PVC containers with 1.10 m in height and 15 cm in diameter. Ozone was injected into the base of the cylindrical column and the corresponding values adopted for the heights of the grain columns were 0.25, 0.50 and 0.75 m. The peanuts were ozonized at concentrations of 1.59 and 2.78 mg L -1 , a temperature of 25 °C and a gas flow rate of 5.0 L min -1 . The ozone saturation times and concentrations were determined and also the quality of the ozonized peanuts. For peanut kernels ozonated at a concentration of 1.59 mg L -1 , saturation times ranging between 222 and 449 min were obtained. Regarding the C Sat /C 0 ratio, values between 0.32 and 0.48 were obtained. For peanut kernels ozonated at a concentration of 2.78 mg L -1 , saturation times between 78 and 251 min were obtained, and the C Sat /C 0 ratio for an initial concentration of 2.78 mg L -1 was between 0.46 and 0.81. It was concluded from the results that an increase in height of the peanut kernel column resulted in an increased saturation time and decreased saturation concentration. There was no change i...

show abstract

Section: Resultsunclassified

Saturação do ozônio em coluna contendo grãos de amendoim e efeito na qualidade

Roberto

Alencar

Ferreira

et al. 2016

Braz. J. Food Technol.

View full text Add to dashboard Cite

show abstract

“…The saturation process with ozone gas at a concentration of 0.45 mg L -1 was studied with peanut grains (ALENCAR et al, 2011). The time to saturate these grains with moisture contents of 7.1 and 10.5% w.b.…”

Section: Resultsmentioning

confidence: 99%

“…The reaction kinetics can be characterized by the decay rate and half-life time. For ozone gas, the reaction kinetics have only been studied in maize (KELLS et al, 2001;HARDIN et al, 2010), wheat (HARDIN et al, 2010) and peanut (ALENCAR et al, 2011) grains.…”

Section: Introductionmentioning

confidence: 99%

“…2017 521 since the ozone concentration is reduced due to the decomposition process. Furthermore, based on the knowledge of the gas reaction kinetics in a porous medium, it is possible to evaluate the technical feasibility of the ozonation process and to estimate the dimensions of industrial systems by using gaseous ozone (ALENCAR et al, 2011). Therefore, this research aimed to evaluate the reaction kinetics of ozone gas in wheat flour based on the saturation time, decay rate and half-life time.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Reaction Kinetics of Ozone Gas in Wheat Flour

et al. 2017

Self Cite

View full text Add to dashboard Cite

ABSTRACT:The implementation of the ozonation process in the milling industry to control insect pests and improve wheat flour qualities requires understanding the behavior of ozone during ozonation. Therefore, this study aimed to investigate the reaction kinetics of ozone gas in wheat flour. Wheat flour ozonation at concentrations of 0.54, 1.07, 1.61 and 2.14 mg L -1 was used in a prototype consisting of a cylinder and a mixing system with a helical thread. The iodometric titration method was used to quantify the ozone concentration in the air stream. The reaction kinetics were characterized by determining the saturation time and the decomposition kinetics (decay rate and half-life time). With increasing ozone concentration, less time was required to saturate the wheat flour. The saturation times were 812, 434, 370 and 342 min for ozone concentrations of 0.54, 1.07, 1.61 and 2.14 mg L -1 , respectively. Increasing the ozone concentration did not influence the constant decay rate and half-life time. The ozone decomposition kinetics could be represented by a first-order model, with a decay rate constant of 0.23±0.008 min -1 and a half-life time of 3.02±0.081 min.

show abstract

“…The O 3 bluish gas half-life time varies from a few seconds to hours, and its stability depends on different factors, among them, temperature. An increase of 10°C results in a reduction of at least 43% in the O 3 half-life [15]. At atmospheric conditions, its half-life is about 30 min and this reaction proceeds more rapidly at higher temperature and lower pressure [16][17][18][19].…”

Section: Ozone Gasmentioning

confidence: 99%

Effectiveness of Ozone Gas Application Methods against Combined Multi-Contaminants in Food

Christ¹,

Savi²,

Scussel³

2017

fph

View full text Add to dashboard Cite

Despite the ozone (known as GRAS -generally recognized as safe) gas treatments published for each food living organism or chemical decontamination, they are not necessarily present or contaminate food individually. Most of the time, they are present all together. Therefore, the most important point, regarding an O 3 application method to be chosen is its effectiveness to all contaminants that may be in the target food. Therefore, ozone gas decontamination methods that gather combined multi-contaminants and their effectiveness in food were surveyed. Both, for inactivation of living organisms (insects, mites, fungi, yeasts and bacteria) and degradation of toxic compounds (pesticides and mycotoxins). They are the main need for an effective and comprehensive commercial decontamination application. This review brings details on O 3 formation energy sources, its application conditions (concentration / time of exposure), container characteristics (volume / material type / sealed or hermetic) and effectiveness for different food (type / contamination level / batch size/moisture content). From the studies and data reported, ozone has shown to be an efficient green agent for combined multi-decontamination, thus prolonging the food storage and shelf life. It does not cause/produce adverse effects on food quality.

show abstract

Decomposition kinetics of gaseous ozone in peanuts

Cited by 30 publications

References 23 publications

Saturação do ozônio em coluna contendo grãos de amendoim e efeito na qualidade

Saturação do ozônio em coluna contendo grãos de amendoim e efeito na qualidade

Reaction Kinetics of Ozone Gas in Wheat Flour

Effectiveness of Ozone Gas Application Methods against Combined Multi-Contaminants in Food

Contact Info

Product

Resources

About