BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//wp-events-plugin.com//6.6.4.4//EN
TZID:Asia/Jerusalem
X-WR-TIMEZONE:Asia/Jerusalem
BEGIN:VEVENT
UID:970@biotech.technion.ac.il
DTSTART;TZID=Asia/Jerusalem:20201104T160000
DTEND;TZID=Asia/Jerusalem:20220202T164952
DTSTAMP:20220512T124720Z
URL:https://biotech.technion.ac.il/events/salmonellas-survival-profiles-in
 -pasteurized-tahini-2/
SUMMARY:Salmonella’s survival profiles in pasteurized tahini
DESCRIPTION:Salmonella enterica is the leading human pathogen responsible f
 or bacterial foodborne outbreaks worldwide. In the recent years\, low wate
 r activity foods have gained the attention as transmission agents\, where 
 contamination can occur at multiple steps along the food chain. Our resear
 ch focuses on the foodstuff tahini\, which is often linked to Salmonella i
 nfection cases. Thermal treatments are suggested to reduce pathogen popula
 tions in low water and high fat content food (LW-HF)\, but they are not ef
 ficient in the removal of Salmonella. Still\, little is known about Salmon
 ella’s behavior and its resistance to high temperatures in a LW-HF envir
 onment. This research\, studies the survival profiles of S. Typhimurium in
  tahini at elevated temperatures by the identification of food related fac
 tors such as water amount (%)\, aw\, and oil (fat) amount (%) that could i
 nfluence this response. Particularly\, aw can modify the thermal resistanc
 e of the bacteria and fat is suggested to provoke a cross-protection effec
 t against high temperatures. We found that thermal treatments are suitable
  to kill only a partial population of Salmonella. 1.7 hours\, 1 hour and 3
 4.6 minutes are required to achieve a 1-log reduction at 70°C\, 80°C and
  90°C respectively. Moreover\, we observed that a second thermal treatmen
 t at 80°C was significantly less effective than the first thermal treatme
 nt\, demanding 3 hours to reach a 1-log reduction. The survival of Salmone
 lla in 100% tahini was almost 4 log higher than in different water/tahini 
 emulsions studied after 30 minutes of treatment. By the addition of only 5
 % of water\, the survival of Salmonella declined considerably (3 log). Lik
 ewise\, the resistance of Salmonella in 100% tahini was approximately 3\,0
 00 times greater than in the 100% tahini oil and tahini oil/tahini mixture
 s after 30 minutes of treatment. Finally\, we analyzed the distribution of
  Salmonella cells throughout tahini oil and observed that they aggregate i
 n 100% oil while they spread in oil/water emulsions (50 w/w %) as single c
 ells\, suggesting a local protection during heat treatments. We conclude t
 hat the current pasteurization process as it is performed today in the ind
 ustry\, might not be enough to kill Salmonella cells in tahini\, and that 
 the “history” of the bacteria has a powerful impact on its tolerance t
 o heat. Furthermore\, we confirmed the crucial role of water activity (aw)
  in the resistance of Salmonella at high temperatures. However\, we believ
 e that fat might not play such an important role in the protection of Salm
 onella against heat as it is suggested.\n\n \n\nAbstract
END:VEVENT
BEGIN:VTIMEZONE
TZID:Asia/Jerusalem
X-LIC-LOCATION:Asia/Jerusalem
BEGIN:STANDARD
DTSTART:20201025T010000
TZOFFSETFROM:+0300
TZOFFSETTO:+0200
TZNAME:IST
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:20210326T030000
TZOFFSETFROM:+0200
TZOFFSETTO:+0300
TZNAME:IDT
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20211031T010000
TZOFFSETFROM:+0300
TZOFFSETTO:+0200
TZNAME:IST
END:STANDARD
END:VTIMEZONE
END:VCALENDAR