Abstract
Here, we examined the antimicrobial effects of soy sauce containing essential oils (EOs) against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes at 22 °C and 4 °C. To screen a variety of combined effects, soy sauce was mixed with six different EOs (carvacrol, thymol, eugenol, trans-cinnamaldehyde, β-resorcylic acid, and vanillin), each at a concentration of 1 mM for 10 min. None of the oils showed bactericidal activity when used alone. Soy sauce combined with carvacrol and thymol induced the greatest antibacterial activity against all tested bacteria; therefore, these oils were further tested at 0.25, 0.5, and 1 mM (0.0039%, 0.0078%, and 0.0157%) for 1, 5, and 10 min at 4 °C and 22 °C. In addition, sensory evaluation of soy sauce containing each EO at 0.25, 0.5, 1, and 2 mM was performed using the nine point hedonic test. Carvacrol or thymol (1 mM) eliminated all the test bacteria (initial population, 7.0-7.5 log CFU/ml) in 1-5 min at 22 °C and within 10 min at 4 °C. L. monocytogenes was slightly more tolerant at 4 °C, which may be attributable to the ability of the cell membrane to adapt to low temperatures. The sensory scores for soy sauce containing EOs were not significantly different from that of soy sauce without EOs (P> 0.05). The stability of EO efficacy in soy sauce was also verified. These results suggest that carvacrol and thymol act synergistically with other factors present in soy sauce to increase antimicrobial activity against major foodborne pathogens at both 4 °C and 22 °C. The synergism may be attributable to the combination of factors (mainly high salt concentration and low pH imparted by organic acids) present in soy sauce and the membrane attacking properties of carvacrol and thymol. This method will facilitate the production of microbiologically safe soy sauce, soy sauce-based marinades, and various marinated foods.
| Original language | English |
|---|---|
| Pages (from-to) | 35-41 |
| Number of pages | 7 |
| Journal | International Journal of Food Microbiology |
| Volume | 217 |
| DOIs | |
| Publication status | Published - 2016 Jan 18 |
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Keywords
- Carvacrol
- E. coli O157:H7
- L. monocytogenes
- S. Typhimurium
- Soy sauce
- Thymol
ASJC Scopus subject areas
- Food Science
- Microbiology
- Safety, Risk, Reliability and Quality
Cite this
Synergism between carvacrol or thymol increases the antimicrobial efficacy of soy sauce with no sensory impact. / Moon, Hyeree; Rhee, Min-Suk.
In: International Journal of Food Microbiology, Vol. 217, 18.01.2016, p. 35-41.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Synergism between carvacrol or thymol increases the antimicrobial efficacy of soy sauce with no sensory impact
AU - Moon, Hyeree
AU - Rhee, Min-Suk
PY - 2016/1/18
Y1 - 2016/1/18
N2 - Here, we examined the antimicrobial effects of soy sauce containing essential oils (EOs) against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes at 22 °C and 4 °C. To screen a variety of combined effects, soy sauce was mixed with six different EOs (carvacrol, thymol, eugenol, trans-cinnamaldehyde, β-resorcylic acid, and vanillin), each at a concentration of 1 mM for 10 min. None of the oils showed bactericidal activity when used alone. Soy sauce combined with carvacrol and thymol induced the greatest antibacterial activity against all tested bacteria; therefore, these oils were further tested at 0.25, 0.5, and 1 mM (0.0039%, 0.0078%, and 0.0157%) for 1, 5, and 10 min at 4 °C and 22 °C. In addition, sensory evaluation of soy sauce containing each EO at 0.25, 0.5, 1, and 2 mM was performed using the nine point hedonic test. Carvacrol or thymol (1 mM) eliminated all the test bacteria (initial population, 7.0-7.5 log CFU/ml) in 1-5 min at 22 °C and within 10 min at 4 °C. L. monocytogenes was slightly more tolerant at 4 °C, which may be attributable to the ability of the cell membrane to adapt to low temperatures. The sensory scores for soy sauce containing EOs were not significantly different from that of soy sauce without EOs (P> 0.05). The stability of EO efficacy in soy sauce was also verified. These results suggest that carvacrol and thymol act synergistically with other factors present in soy sauce to increase antimicrobial activity against major foodborne pathogens at both 4 °C and 22 °C. The synergism may be attributable to the combination of factors (mainly high salt concentration and low pH imparted by organic acids) present in soy sauce and the membrane attacking properties of carvacrol and thymol. This method will facilitate the production of microbiologically safe soy sauce, soy sauce-based marinades, and various marinated foods.
AB - Here, we examined the antimicrobial effects of soy sauce containing essential oils (EOs) against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes at 22 °C and 4 °C. To screen a variety of combined effects, soy sauce was mixed with six different EOs (carvacrol, thymol, eugenol, trans-cinnamaldehyde, β-resorcylic acid, and vanillin), each at a concentration of 1 mM for 10 min. None of the oils showed bactericidal activity when used alone. Soy sauce combined with carvacrol and thymol induced the greatest antibacterial activity against all tested bacteria; therefore, these oils were further tested at 0.25, 0.5, and 1 mM (0.0039%, 0.0078%, and 0.0157%) for 1, 5, and 10 min at 4 °C and 22 °C. In addition, sensory evaluation of soy sauce containing each EO at 0.25, 0.5, 1, and 2 mM was performed using the nine point hedonic test. Carvacrol or thymol (1 mM) eliminated all the test bacteria (initial population, 7.0-7.5 log CFU/ml) in 1-5 min at 22 °C and within 10 min at 4 °C. L. monocytogenes was slightly more tolerant at 4 °C, which may be attributable to the ability of the cell membrane to adapt to low temperatures. The sensory scores for soy sauce containing EOs were not significantly different from that of soy sauce without EOs (P> 0.05). The stability of EO efficacy in soy sauce was also verified. These results suggest that carvacrol and thymol act synergistically with other factors present in soy sauce to increase antimicrobial activity against major foodborne pathogens at both 4 °C and 22 °C. The synergism may be attributable to the combination of factors (mainly high salt concentration and low pH imparted by organic acids) present in soy sauce and the membrane attacking properties of carvacrol and thymol. This method will facilitate the production of microbiologically safe soy sauce, soy sauce-based marinades, and various marinated foods.
KW - Carvacrol
KW - E. coli O157:H7
KW - L. monocytogenes
KW - S. Typhimurium
KW - Soy sauce
KW - Thymol
UR - http://www.scopus.com/inward/record.url?scp=84944691230&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84944691230&partnerID=8YFLogxK
U2 - 10.1016/j.ijfoodmicro.2015.10.009
DO - 10.1016/j.ijfoodmicro.2015.10.009
M3 - Article
VL - 217
SP - 35
EP - 41
JO - International Journal of Food Microbiology
JF - International Journal of Food Microbiology
SN - 0168-1605
ER -