Radiation process to inactivate microorganisms especially in spices has been used widely in food ... more Radiation process to inactivate microorganisms especially in spices has been used widely in food industry. This application’s most usage type is irradiation process. Irradiation is not used only sterilization purpose in food industry, generally it is used for decreasing microbiological count and it is also called as "cold pasteurization". Gram negative bacteria and pathogen that contain enteric species such as Salmonella and Shigella are generally more sensitive than vegetative forms of Gram positive bacteria. When comparing to vegetative forms of bacteria and spore forms, spore forms are more resistant. Because of that, spores water content (10%) are less than vegetative cell (70%), DNA in spores are more resistant and chemical compounds such as dipicolinic acid in spore structure ensure to resistance. Spore forming bacteria that increased water content in germination period decrease radiation resistance. Many mold’s radiation resistance is similar to vegetative forms of ...
Turkish Journal of Veterinary & Animal Sciences, 2004
The death kinetics of Escherichia coli O157:H7, E. coli type 1 and total coliforms after irradiat... more The death kinetics of Escherichia coli O157:H7, E. coli type 1 and total coliforms after irradiation treatment in minced beef were evaluated to analyze the effect of increasing irradiation doses. Irradiation doses ranging from 0.0 kGy to 1.5 kGy were evaluated for reducing numbers of E. coli during frozen storage conditions at –18 oC for 30 days. D10 values of E. coli O157:H7, E. coli type 1, and total coliforms were 0.245 kGy, 0.552 kGy and 0.293 kGy, respectively. An irradiation dose of 1.5 kGy was shown to inactivate 105 MPN/g of serotype O157:H7 and 103 MPN/g of E. coli type 1. This inactivation level might be considered safe for the consumption of minced beef. Finally, E. coli type 1 was found to be a suitable indicator for assessing the impact of irradiation on E. coli O157:H7 serotype. There was no significant change in numbers of bacteria during frozen storage.
Isinlama; kontrollu iyonlastirici radyasyon kaynagi kullanilarak tip, biyoloji, tarim, endustriye... more Isinlama; kontrollu iyonlastirici radyasyon kaynagi kullanilarak tip, biyoloji, tarim, endustriyel kimya, gida endustrisi vb. pek cok alanda uygulanan bir prosestir. Gida endustrisinde bu proses ile gidalarin raf omru uzatilir, gida kayiplari azaltilir, gidanin mikrobiyolojik guvenilirligi gelistirilir ve buna bagli olarak cesitli inhibitorlerin (katki maddeleri, fumigantlar vb.) kullanimi azaltilir. Bu derlemede agirlikli olarak gidalarda isinlama isleminin mikroorganizmalar uzerindeki etkisi anlatilmistir.
Abstract The Ottoman Archives have one of the richest archive collections in the world. However, ... more Abstract The Ottoman Archives have one of the richest archive collections in the world. However, not all the archived documents are well preserved and some undergo biodeterioration. Therefore, a rapid and promising treatment method is necessary to preserve the collection for following generations as heritage. Radiation presents as an alternative for the treatment of archival materials for this purpose. In this study, we conducted a survey to determine the contamination species and the D10 values of the samples obtained from the shelves of the Ottoman Archives. The samples also included several insect pests collected at using a pheromone trap placed in the archive storage room. With the exception of few localized problems, no active pest presence was observed. The D10 values of mold contamination and reference mold (A. niger) were found to be 1.0 and 0.68 kGy, respectively. Based on these results, it can be concluded that an absorbed dose of 6 kGy is required to remove the contamination from the materials stored in the Ottoman Archives.
Mikroskobik yontemler, mikrobiyel hucrelerin varliginin belirlenmesinde cok hizli yontemlerdir. S... more Mikroskobik yontemler, mikrobiyel hucrelerin varliginin belirlenmesinde cok hizli yontemlerdir. Standart kulturel yontemler ile karsilastirildiginda canli ve olu hucrelerin beraberce sayilmasi gibi bir dezavantaji bulunmakla beraber, hammaddenin mikrobiyel durumu hakkinda bilgi vermesi acisindan avantaj da tasimaktadir. DEFT, basit direk mikroskobik sayim yontemlerinden yaklasik 100 kat daha duyarli ve sonuclari kulturel sayim ile kiyaslanabilecek kadar dogru sonuclar veren bir yontemdir. DEFT yontemi canli ve olu hucreler arasindaki ayrimi saglamaktadir. Fluorochrome isaretli antikorlarin kullanimi ile belirli mikroorganizmalarin tur duzeyinde tespiti de mumkundur.
255 minced beef, 101 soudjouk and 50 uncooked hamburger samples were analyzed for the presence of... more 255 minced beef, 101 soudjouk and 50 uncooked hamburger samples were analyzed for the presence of Escherichia coli O157:H7 serotype. m-EC and LST broths were used as selective enrichment media and SMAC agar was used as a selective isolation medium. A total of 3 E. coli O157 were isolated by conventional culture techniques; one from each of minced beef, uncooked hamburger and soudjouk but none were identified as the H7 serotype. For determination of selective media-growing cohabitant bacteria, 2645 isolates were obtained from SMAC agar. Results showed that E. coli type 1, Hafnia alvei and Citrobacter freundii were dominant competitive flora. As selective enrichment broth-growing cohabitant microflora existed at higher levels, it was too difficult to isolate E. coli O157 from these mixed flora. Therefore, conventional methods are not suitable for these types of products, because of isolation difficulties and failure to confirm.
To reduce the analysis time needed for the enumeration of Escherichia coli, a rapid fluorogenic m... more To reduce the analysis time needed for the enumeration of Escherichia coli, a rapid fluorogenic method (MUG) which takes only 48 h was compared with the standard most probable number (MPN) method which takes 6 days as described in the International Standards Organization (ISO). This study provides reliability data for the fluorogenic method applied to certain foods. Both methods were applied to 500 food samples which were analysed for E. coli enumeration. Agreement between the two methods was found in 409 (81 x 8%) samples; 81 (16 x 2%) samples gave higher values by the fluorogenic method, and only 10 (2 x 0%) samples were more effectively assayed by the ISO method. According to statistical analysis, the reliability between the methods was r = 0 x 9706, r(2) = 0 x 9421 and Cronbach's alpha = 0 x 9851. While all three values showed a high degree of correlation (P < 0 x 0001) between the two methods, McNemar's test demonstrated a significant difference between them, indicating that the MUG method was more reliable than the ISO method. The data suggest that the fluorogenic method is more reliable and shorter to perform than the standard ISO method. Comparison of the two methods may provide a rapid and more reliable alternative for the enumeration of E. coli in food samples.
Radiation process to inactivate microorganisms especially in spices has been used widely in food ... more Radiation process to inactivate microorganisms especially in spices has been used widely in food industry. This application’s most usage type is irradiation process. Irradiation is not used only sterilization purpose in food industry, generally it is used for decreasing microbiological count and it is also called as "cold pasteurization". Gram negative bacteria and pathogen that contain enteric species such as Salmonella and Shigella are generally more sensitive than vegetative forms of Gram positive bacteria. When comparing to vegetative forms of bacteria and spore forms, spore forms are more resistant. Because of that, spores water content (10%) are less than vegetative cell (70%), DNA in spores are more resistant and chemical compounds such as dipicolinic acid in spore structure ensure to resistance. Spore forming bacteria that increased water content in germination period decrease radiation resistance. Many mold’s radiation resistance is similar to vegetative forms of ...
Turkish Journal of Veterinary & Animal Sciences, 2004
The death kinetics of Escherichia coli O157:H7, E. coli type 1 and total coliforms after irradiat... more The death kinetics of Escherichia coli O157:H7, E. coli type 1 and total coliforms after irradiation treatment in minced beef were evaluated to analyze the effect of increasing irradiation doses. Irradiation doses ranging from 0.0 kGy to 1.5 kGy were evaluated for reducing numbers of E. coli during frozen storage conditions at –18 oC for 30 days. D10 values of E. coli O157:H7, E. coli type 1, and total coliforms were 0.245 kGy, 0.552 kGy and 0.293 kGy, respectively. An irradiation dose of 1.5 kGy was shown to inactivate 105 MPN/g of serotype O157:H7 and 103 MPN/g of E. coli type 1. This inactivation level might be considered safe for the consumption of minced beef. Finally, E. coli type 1 was found to be a suitable indicator for assessing the impact of irradiation on E. coli O157:H7 serotype. There was no significant change in numbers of bacteria during frozen storage.
Isinlama; kontrollu iyonlastirici radyasyon kaynagi kullanilarak tip, biyoloji, tarim, endustriye... more Isinlama; kontrollu iyonlastirici radyasyon kaynagi kullanilarak tip, biyoloji, tarim, endustriyel kimya, gida endustrisi vb. pek cok alanda uygulanan bir prosestir. Gida endustrisinde bu proses ile gidalarin raf omru uzatilir, gida kayiplari azaltilir, gidanin mikrobiyolojik guvenilirligi gelistirilir ve buna bagli olarak cesitli inhibitorlerin (katki maddeleri, fumigantlar vb.) kullanimi azaltilir. Bu derlemede agirlikli olarak gidalarda isinlama isleminin mikroorganizmalar uzerindeki etkisi anlatilmistir.
Abstract The Ottoman Archives have one of the richest archive collections in the world. However, ... more Abstract The Ottoman Archives have one of the richest archive collections in the world. However, not all the archived documents are well preserved and some undergo biodeterioration. Therefore, a rapid and promising treatment method is necessary to preserve the collection for following generations as heritage. Radiation presents as an alternative for the treatment of archival materials for this purpose. In this study, we conducted a survey to determine the contamination species and the D10 values of the samples obtained from the shelves of the Ottoman Archives. The samples also included several insect pests collected at using a pheromone trap placed in the archive storage room. With the exception of few localized problems, no active pest presence was observed. The D10 values of mold contamination and reference mold (A. niger) were found to be 1.0 and 0.68 kGy, respectively. Based on these results, it can be concluded that an absorbed dose of 6 kGy is required to remove the contamination from the materials stored in the Ottoman Archives.
Mikroskobik yontemler, mikrobiyel hucrelerin varliginin belirlenmesinde cok hizli yontemlerdir. S... more Mikroskobik yontemler, mikrobiyel hucrelerin varliginin belirlenmesinde cok hizli yontemlerdir. Standart kulturel yontemler ile karsilastirildiginda canli ve olu hucrelerin beraberce sayilmasi gibi bir dezavantaji bulunmakla beraber, hammaddenin mikrobiyel durumu hakkinda bilgi vermesi acisindan avantaj da tasimaktadir. DEFT, basit direk mikroskobik sayim yontemlerinden yaklasik 100 kat daha duyarli ve sonuclari kulturel sayim ile kiyaslanabilecek kadar dogru sonuclar veren bir yontemdir. DEFT yontemi canli ve olu hucreler arasindaki ayrimi saglamaktadir. Fluorochrome isaretli antikorlarin kullanimi ile belirli mikroorganizmalarin tur duzeyinde tespiti de mumkundur.
255 minced beef, 101 soudjouk and 50 uncooked hamburger samples were analyzed for the presence of... more 255 minced beef, 101 soudjouk and 50 uncooked hamburger samples were analyzed for the presence of Escherichia coli O157:H7 serotype. m-EC and LST broths were used as selective enrichment media and SMAC agar was used as a selective isolation medium. A total of 3 E. coli O157 were isolated by conventional culture techniques; one from each of minced beef, uncooked hamburger and soudjouk but none were identified as the H7 serotype. For determination of selective media-growing cohabitant bacteria, 2645 isolates were obtained from SMAC agar. Results showed that E. coli type 1, Hafnia alvei and Citrobacter freundii were dominant competitive flora. As selective enrichment broth-growing cohabitant microflora existed at higher levels, it was too difficult to isolate E. coli O157 from these mixed flora. Therefore, conventional methods are not suitable for these types of products, because of isolation difficulties and failure to confirm.
To reduce the analysis time needed for the enumeration of Escherichia coli, a rapid fluorogenic m... more To reduce the analysis time needed for the enumeration of Escherichia coli, a rapid fluorogenic method (MUG) which takes only 48 h was compared with the standard most probable number (MPN) method which takes 6 days as described in the International Standards Organization (ISO). This study provides reliability data for the fluorogenic method applied to certain foods. Both methods were applied to 500 food samples which were analysed for E. coli enumeration. Agreement between the two methods was found in 409 (81 x 8%) samples; 81 (16 x 2%) samples gave higher values by the fluorogenic method, and only 10 (2 x 0%) samples were more effectively assayed by the ISO method. According to statistical analysis, the reliability between the methods was r = 0 x 9706, r(2) = 0 x 9421 and Cronbach's alpha = 0 x 9851. While all three values showed a high degree of correlation (P < 0 x 0001) between the two methods, McNemar's test demonstrated a significant difference between them, indicating that the MUG method was more reliable than the ISO method. The data suggest that the fluorogenic method is more reliable and shorter to perform than the standard ISO method. Comparison of the two methods may provide a rapid and more reliable alternative for the enumeration of E. coli in food samples.
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