TY - JOUR
T1 - Viability of sprout seeds as affected by treatment with aqueous chlorine dioxide and dry heat, and reduction of Escherichia coli O157
T2 - H7 and Salmonella enterica on pak choi seeds by sequential treatment with chlorine dioxide, drying, and dry heat
AU - Choi, Seonyeong
AU - Beuchat, Larry R.
AU - Kim, Hoikyung
AU - Ryu, Jee Hoon
N1 - Funding Information:
This study was supported by Youlchon Foundation and by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2013R1A2A2A01068475 )
Publisher Copyright:
© 2015 Elsevier Ltd.
PY - 2016/4/1
Y1 - 2016/4/1
N2 - Germination rates of 11 types of sprout seeds (alfalfa, broccoli, kohlrabi, kyona, mustard, pak choi, red kohlrabi, red radish, red young radish, tatsoi, and violet radish) treated with ClO2 (200 μg/ml, 5 min) or dry-heat (80 °C/23% relative humidity [RH], 24 h) were determined. Pak choi, red radish, and tatsoi seeds showed highest tolerance to both ClO2 and dry-heat treatments. Next, pak choi seeds were inoculated with Escherichia coli O157:H7 (5.4 log CFU/g) or Salmonella enterica (4.8 log CFU/g) and sequentially treated with ClO2 (200 μg/ml, 5 min), drying (45 °C/23% RH, 24 h), and dry heat (80 °C/23% RH, 48 h). E. coli O157:H7 was inactivated, but S. enterica was not eliminated (>3.8 log CFU/g reduction). Pak choi seeds inoculated with the pathogens were treated with ClO2, drying, and dry heat and subsequently sprouted for 5 days. When seeds were not completely decontaminated, initial populations of E. coli O157:H7 and S. enterica on seeds (<1.0 log CFU/g) increased to >5.3 and > 8.4 log CFU/g of sprouts, respectively. This study shows that sequential treatments of pak choi seeds with ClO2, drying, and dry heat are effective in reducing large numbers of E. coli O157:H7 and S. enterica without loss of seed viability.
AB - Germination rates of 11 types of sprout seeds (alfalfa, broccoli, kohlrabi, kyona, mustard, pak choi, red kohlrabi, red radish, red young radish, tatsoi, and violet radish) treated with ClO2 (200 μg/ml, 5 min) or dry-heat (80 °C/23% relative humidity [RH], 24 h) were determined. Pak choi, red radish, and tatsoi seeds showed highest tolerance to both ClO2 and dry-heat treatments. Next, pak choi seeds were inoculated with Escherichia coli O157:H7 (5.4 log CFU/g) or Salmonella enterica (4.8 log CFU/g) and sequentially treated with ClO2 (200 μg/ml, 5 min), drying (45 °C/23% RH, 24 h), and dry heat (80 °C/23% RH, 48 h). E. coli O157:H7 was inactivated, but S. enterica was not eliminated (>3.8 log CFU/g reduction). Pak choi seeds inoculated with the pathogens were treated with ClO2, drying, and dry heat and subsequently sprouted for 5 days. When seeds were not completely decontaminated, initial populations of E. coli O157:H7 and S. enterica on seeds (<1.0 log CFU/g) increased to >5.3 and > 8.4 log CFU/g of sprouts, respectively. This study shows that sequential treatments of pak choi seeds with ClO2, drying, and dry heat are effective in reducing large numbers of E. coli O157:H7 and S. enterica without loss of seed viability.
KW - Chlorine dioxide
KW - Dry-heat
KW - Escherichia coli O157:H7
KW - Pak choi seeds
KW - Salmonella enterica
KW - Sequential treatment
KW - Sprout seeds
UR - http://www.scopus.com/inward/record.url?scp=84948960335&partnerID=8YFLogxK
U2 - 10.1016/j.fm.2015.10.007
DO - 10.1016/j.fm.2015.10.007
M3 - Article
AN - SCOPUS:84948960335
VL - 54
SP - 127
EP - 132
JO - Food Microbiology
JF - Food Microbiology
SN - 0740-0020
ER -