No abstract

Control de Salmonella y Escherichia coli mediante el uso de quitosano y ácido láctico en filetes de pollo refrigerados Chitosan (0.5%, 1%, 2%), lactic acid 1%, and combination of chitosan 2% and lactic acid 1% were used as treatment of chicken fillets stored at 4°C to control Salmonella typhimurium (S. Typhimurium) and Escherichia coli (E. coli). The results indicated that chitosan 0.5% did not reduce the count of S. Typhimurium or E. coli. Meanwhile, chitosan 1% significantly reduced E. coli count by 1 log; however, no reduction effect could be observed for S.Typhimurium count. Chitosan 2%, lactic acid 1%, and combination of chitosan 2% and lactic acid 1% significantly reduced the count of S. Typhimurium and E. coli through the storage time (by about 1.2-1.4 log) and E. coli (by about 1 log). Treatment with lactic acid 1% significantly reduced overall sensory score of chicken fillet till the third day of storage. Chitosan has no adverse effect on sensory properties of the samples. RESUMENEn el presente estudio se utilizó quitosano (al 0.5%, 1% y 2%,), ácido láctico al 1% y una combinación de quitosano al 2% y ácido láctico al 1% como tratamiento de filetes de pollo almacenados a 4 °C con el objetivo de controlar el S. Typhimurium y la E. coli. Los resultados permitieron constatar que el quitosano al 0.5% no redujo el recuento de S. Typhimurium ni el de E. coli. Además, se comprobó que si bien el quitosano al 1% redujo significativamente el recuento de E. coli en 1 log; no se observaron efectos de reducción en el recuento de S. Typhimurium. Asimismo, se demostró que, durante el tiempo de almacenamiento, el quitosano al 2%, el ácido láctico al 1% y la combinación de quitosano al 2% y ácido láctico al 1% redujeron significativamente el recuento de S. Typhimurium (en aproximadamente 1.2 a 1.4 log) y el de E. coli (en aproximadamente 1 log). El tratamiento con ácido láctico al 1% redujo significativamente la puntuación sensorial global del filete de pollo hasta el tercer día de almacenamiento. El quitosano no tiene efectos adversos en las propiedades sensoriales de las muestras.

Storage of table eggs in refrigeration is a popular habit but it may be lead to different degree of contamination with pathogens and increase the risks of illness in humans. A total of 75 chicken table eggs (grades II) were collected from 5 farms (15 of each) in Alexandria province and which were stored in refrigerator at 5 °C. The collected eggs were divided into three groups (25 of each): 1 st group at zero time of storage (at laying day), 2 nd group after one week of storage and 3 rd group after two weeks of storage. They were analyzed for bacterial and fungal contamination on their shells and internal contents. The results of the current study indicated that the egg shells had the highest while the internal contents had the lowest load of both bacterial and fungal contamination. The isolated bacterial species were identified into E.

The highest concentration of copper was in liver while the lowest was in hair for all animals. The results indicated that sheep had the higher liver copper concentrations, followed by camels, buffaloes, goats and then cows.

Kariesh cheese is a highly nutritive soft acid cheese made from naturally fermented skimmed milk, mainly manufactured at home by small holders and sold at local markets. Due to unhygienic condition during manufacturing and low quality raw milk, many outbreaks of human brucellosis were reported. This study was done to evaluate the use of acetic and citric acids, as natural organic acids, to produce kariesh cheese instead of the traditional method to control Brucella infection. Sensory evaluation revealed that all treatments didn't differ (P>0.05) than control except 2% citric acid which characterized to a little extent by lemon flavor, crudeness body and texture and less whiter color than other treatments. B. meletensis strains didn't affected by acetic (1%) or citric (1.5%) acids, but both of them were completely inhibited by acetic (1.5%), or have 4 log reduction by citric (2%) acids. For B. abortus the field and S19 strains were completely inhibited by 1% acetic acid, but citric acid 2% significantly (P<0.05) reduced the count of S19 and 544 strains by 4.46 and 3.32 log cfu/g, respectively. These results suggested that treatment of raw skimmed milk with acetic acid 1.5% or citric acid 2% is a good alternative for production of hygienic kariesh cheese to control brucellosis in human.