Post on 08-Sep-2018
Predictive Microbiology for Spices and Herbs
1 June 2016 I Stratakou, HWM den Besten and MH Zwietering
Food Safety
Objective(FSO)
Appropriate Level Of Protection
(ALOP)
ALOP & FSO
Model for Spices and Herbs
Consumers
Harvest
DecontaminationStorage
Process steps
Log N (c
fu/g)
ICMSFH0- ΣR+ΣI < FSO
Food Safety Objective-FSO
Η0
ΣR ΣI=ΣG+ΣC
FSO
Zwietering, 2005
ΣI~0
FSO
ALOP
ReductionInitiallevels
Own Meta-analysis
Existing databases
Experiments
Prevalence/levels
Own Meta-analysis
Existing databases
Experiments
Parameters (±PIs)
Dose/Response
Consumption
Mortality rates
ALOP & FSO
Deterministic
95% percentile
StochasticInactivation/
Tenacity
Foodborne Diseases in Spices
Salmonella spp. in powder paprika● Other agent/matrices
ALOP: 1 death per year per 108 people● 128 illnesses per year per 108 people
Salmonella spp. FSO=-5.4 log cfu/g
FSO-5.4 log cfu/g
Log
N (
cfu/
g)
FSO Factors-H0
Prevalence of Salmonella spp. in spices● EU data: RASFF & EFSA data=0.03● Published studies: not only EU=0.05
● WHO data: global (& EU) data=0.03
H0=-3 log cfu/g Batch of oregano tested, absence of salmonellas
Η0-3FSO=-5.4
Log
N (
cfu/
g)
FSO Factors-ΣRInactivation
ΣRInact=ΣRThermal /ΣRIrradiation
Η0=-3
Log
N (
cfu/
g)
FSO=-5.4
Other meta-analyses
Experimental findings
Irradiation
‐9
‐8
‐7
‐6
‐5
‐4
‐3
‐2
‐1
00 5 10 15 20 25
Survival (log
cfu/g)
Dose (kGy)
Spores
Cells sporeformers
Cells non‐sporeformers
N= 71 D10=4.3(PI±2.1)
N=77 D10=3.2(PI±2)
N=111 D10=1.8(PI±3.1)
Irradiation
‐9
‐8
‐7
‐6
‐5
‐4
‐3
‐2
‐1
00 5 10 15 20 25
Survival (log
cfu/g)
Dose (kGy)
Cells non‐sporeformersN=111 D10=1.8(PI±3.1)
Irradiation
‐9
‐8
‐7
‐6
‐5
‐4
‐3
‐2
‐1
00 5 10 15 20 25
Survival (log
cfu/g)
Dose (kGy)
Cells non‐sporeformers
S.Infantis N=30 D10=1.3
N=111 D10=1.8(PI±3.1)
1.8
0.7
1.3
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Cells non-sporeformers
D1
0 (
kGy)
Spices
van Gerwen et al, 1999
S. Infantis
FSO Factors-ΣRInactivation
ΣRInact=ΣRIrradiation
Inactivation Factors: Spores & Gram stain● Dirrad value spores: 4.3(PI±2.1) kGy
● Dirrad value vegetative: 1.8(PI±3.1) kGy
Irradiation of paprika: 10 kGy-5.5 log cfu/g
ΣR-8.5 log cfu/g
Η0=-3
Log
N (
cfu/
g) FSO=-5.4
FSO Factors-ΣRtenacity
ΣRtenacity Survival in storage conditions
FSO=-5.4
Own meta-analysis
Tenacity studies
-3
Log
N (
cfu/
g)
-8.5
Survival
0.0
1.0
2.0
3.0
4.0
5.0
0 10 20 30 40 50
Log D (lo
g days)
T (0C)
Gram pos(spores)
Gram neg(veg)N=126 D=2.9 (PI±0.7)
N=38 D=2.2 (PI±1.3)
Survival
0.0
1.0
2.0
3.0
4.0
5.0
0 10 20 30 40 50
Log D (lo
g days)
T (0C)
Gram neg(veg)N=38 D=2.2 (PI±1.3)
Survival
0.0
1.0
2.0
3.0
4.0
5.0
0 10 20 30 40 50
Log D (log days)
T (0C)
Gram neg(veg)
InfantisS.Log D=2
N=38 D=2.2 (PI±1.3)
FSO Factors-ΣRtenacity
ΣRtenacity Survival in storage conditions
Tenacity Factors: Spores, Gram stain● Log Dsurv spores: 2.9(PI±0.7) log days=2.3 years
● Log Dsurv vegetative: 2.2(PI±1.3) log days=0.5 years
20 0C, 0.46 aw Storage of paprika: 1 year~-2 log cfu/g
ΣR≈-10.5 log cfu/gLog
N (
cfu/
g) FSO=-5.4-3
-8.5
Salmonella spp. in Paprika Powder
FSO
Log
N (
cfu/
g) -3
-5.1
-8.5
-5.1
-2.1
-10.5
0.4
-7.1
Conclusions
Framework for quantification of control in the spice/herbchain
Determined the effect of variability factors
Scenario analysis
Acknowledgments
Jen Banach Tom Kim Dongmin Emi Amalia Budri Gerrald de Vries Ilias Apostolakos FUCHS
Thank you for your attention
Questions?
21
ALOP-FSO
Mortality rate Salmonella=0.78%Ill=death/mortality rate=1/0.0078=128
Ill p.p/p.d.=r*Dose=r*average consumption*concentrationR=0.0075Ill p.y/population=ill*365*108
Average consumption=weight*portions=1.8/16=0.11gConcentration=10^FSOFSO=log(ill/r*avcon*365*108)=log(128/0.11*365*108)=-5.4 log cfu/g
22
Factors
Levels = prevalence of 0.03 equals to 3 positive (1 cfupresent) in 100 samples, if 25g per sample then 3cfu/2500g=0.0012=-3log cfu/g
Irradiation=-0.55*10=-5.5 log cfu/g
Storage= 2.39-0.0055*20=2.28 Log D D=190 days 1 log reduction for 365 days=1.92 log cfu/g reduction
23
Thermal
‐2.5
‐1.5
‐0.5
0.5
1.5
2.5
65 85 105 125
Log D (log
min)
T (°C)
Bacillus cereus