RESUMO
Increased meat and egg production leads to concomitant changes in poultry practices, including the indiscriminate use of formaldehyde to sanitize hatching eggs. Although this sanitizer aids in the increase in poultry production, its toxic potential for man and for avian embryos represents an obstacle to its long-term use. This review assesses whether essential oils fit into the context of hatching egg contamination, reviewing their antimicrobial efficiency, toxicity to poultry embryos and chicks, and their sanitizing effects on poultry production parameters. Studies have indicated that, because they are safer, most of the essential oils studied can be a potential substitute for formaldehyde for minimizing microbial exposure of hatching eggs and embryos. However, complementary studies on the microbiological profile of embryos and chicks hatched from eggs sanitized with essential oils need to be carried out and the economic feasibility of the candidate products should also be considered.
RESUMO
Neutral Electrolyzed Water (NEW) was tested in vitro and on artificially contaminated eggs against Salmonella enterica subsp. enterica or Escherichia coli. The antibacterial effect was measured 30â¯s after treatment. NEW microbicide activity results were compared against 2% citric acid and 0.9% saline solutions. NEW caused an in vitro decrease in Salmonella titers by Ë5.56 Log10 CFU mL-1 and in artificially contaminated eggs by Ë1.45 Log10 CFU/egg. When it was tested against E. coli, it decreased in vitro bacterial titers by Ë3.28 Log10 CFU mL-1 and on artificially contaminated eggs by Ë6.39 Log10 CFU/egg. The 2% citric acid solution caused an in vitro decrease of 0.4 Log10 CFU mL-1 of Salmonella and E. coli and on eggs artificially contaminated with E. coli or Salmonella there was a decrease of 0.06 and 0.62 Log10 CFU/egg respectively. We evaluated egg cuticle integrity by scanning electron microscopy after treatments with evaluated solutions; the 2% citric acid solution caused damage to the cuticle and exposed eggshell pores and no interaction of NEW or NaCl with the cuticle was observed. NEW treatment showed a fast-bactericidal effect in vitro and table eggs.
Assuntos
Antibacterianos/farmacologia , Casca de Ovo/microbiologia , Escherichia coli/efeitos dos fármacos , Salmonella enterica/efeitos dos fármacos , Água/farmacologia , Animais , Antibacterianos/química , Contagem de Colônia Microbiana , Casca de Ovo/efeitos dos fármacos , Ovos/microbiologia , Eletrólise , Escherichia coli/crescimento & desenvolvimento , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Salmonella enterica/crescimento & desenvolvimento , Água/químicaRESUMO
A survey of the presence of Salmonella in chicken eggshell and yolk, obtained on the retail market in Campinas, SP, Brazil, was carried out in order to study the effect of storage time and temperature on the Salmonella enteritidis (SE) multiplication on the eggshell and yolk of eggs artificially contaminated by contact with litter and, also, the multiplication of SE in egg white, whippet egg white and glace, storage under different conditions of temperature. It was also studied the effect of egg dipping disinfections into two solutions, on the bacterial and SE counting on contaminated eggshell. From the 124 samples tested on the survey, 12 (9.6%) and four (3.2%) were positive for Salmonella on the eggshell and in the yolk, respectively. SE was the only detected sorovar. SE remained viable in artificially contaminated eggshells for a period of 21 days in eggs kept at both room temperature (25ºC), and refrigeration (4-8ºC). Migration of SE from the eggshell to the yolk was detected after 24 hours of storage, under both conditions with a greater level on the eggs kept at room temperature. The refrigerated conditions did not affect SE migration, although its replication was reduced. Egg white, whipped egg white and glace were shown not to be good substrates for SE growth, considering there was a reduction of one log10 titer in the original contamination of these foods, kept under both time conditions (24 and 168 hours for glace) and temperatures. In this study, egg dipping in a warm solution (45ºC) of a commercially available quaternary ammonium compound (400ppm) using the same conditions was more effective in eggshell disinfections than the chlorinated compound (50.2ppm) on the total mesophilic bacteria and SE reduction.
Este trabalho teve por objetivos verificar a ocorrência de salmonelas na casca e na gema de ovos de galinha distribuídos em pontos de venda da cidade de Campinas-SP, estudar o efeito do tempo e da temperatura de armazenagem sobre a multiplicação de Salmonella enteritidis (SE) na casca e na gema de ovos contaminados artificialmente por contato com maravalhas e na multiplicação de SE em clara e preparações artificialmente contaminadas e verificar o efeito da desinfecção de ovos por imersão em duas soluções desinfetantes sobre a contagem bacteriana e de SE da casca de ovos artificialmente contaminados. Das 124 amostras com 10 ovos cada, obtidas no comércio, 12 (9,6%) e quatro (3,2%) foram positivas para salmonelas na casca e na gema, respectivamente. SE foi o único sorovar identificado. Ovos experimentalmente contaminados apresentaram SE na casca pelo período de estudo de 21 dias tanto nos mantidos em temperatura ambiente, como em refrigeração. Houve migração da contaminação de SE da casca para a gema a partir de 24 horas, com maior intensidade nos ovos mantidos em temperatura ambiente. Clara de ovos, clara batida e glacê não se mostraram substratos apropriados para a multiplicação de SE quando armazenados tanto em temperatura ambiente como em refrigeração. Não houve aumento da contaminação original no período de 24 e 168 horas do estudo. Ao contrário, houve redução de um ciclo logaritmo da contaminação original na preparação de glacês mantidas nas duas condições de armazenagem. A desinfecção da casca de ovos com solução do composto quaternário de amônia na dosagem de 400ppm e aquecida a 45ºC foi mais eficiente do que quando se utilizaram 50,2ppm de cloro, nas mesmas condições de uso, tanto na redução de mesófilos totais como para SE.