Transcript Sanitizer Options, Dosing, Monitoring, and Documenting

9 am-9:15
9:15-9:45
9:45-10:30
10:30-10:40
10:40-11:50
11:50-Noon
Welcome and Introductions
Postharvest water sanitation overview
Choosing the Right Sanitizer and Monitoring it the Right Way
Break
Facility Sanitation Basics and Environmental Monitoring Programs
Q&A Evaluation and Wrap up.
Trevor Suslow
UC Davis - Department of Plant Sciences
[email protected]
Treatment of process water to inactivate ;
 Pathogenic bacteria
 Plant pathogens
 Human pathogens

Spoilage Microbes
 Fungi
 Bacteria
 Yeast


Human Parasites
Viruses
 Human pathogens
• Multiple chemical choices
• Multiple product types
• Diverse microbe types
• Different load throughput
• Varying wash/cooling conditions
• Different equipment designs
• Different retention times
Oxidizing Reagent
Ozone
Hydrogen Peroxide
Permanganate
Hypochlorous Acid
Chlorine Gas
Hypobromous Acid
Oxygen
Bromine
Hypoiodous Acid
Chlorine Dioxide
Hypochlorite
Chlorite
Iodine
Oxidizing Potential
2.07
1.77
1.67
1.49
1.36
1.33
1.23
1.09
0.99
0.95
0.94
0.76
0.54



Remains the most common sanitizer
As chlorine gas –
 Cl2 + H2O → HOCL + HCL
Sodium hypochlorite (bleach)
_
+
 NaOCl + H2O → HOCl + Na + OH
_
++
 Ca(OCl)2 + 2H2O → 2HOCl + Ca + 2OH
68% Ca(OCl)2
tablets
120.0%
Relative abundances
100.0%
80.0%
Cl2
HOCl
OCl
60.0%
40.0%
20.0%
0.0%
0
2
4
6
8
pH
10
12
14
Combined Chlorine
Total Chlorine
Free Chlorine
pH
6.5
7.0
7.5
8.0
HOCl
95%
80%
50%
20%
-OCl
5%
20%
50%
80%
Combined Chlorine
Total Chlorine
Free Chlorine
pH
6.5
7.0
7.5
8.0
HOCl
95%
80%
50%
20%
-OCl
5%
20%
50%
80%

Peak Chlorine Demand
 Maximum amount of chlorine in a batch of water
that is “used up” by soil and organic materials
added with product during washing
 Determining Peak Cl Demand helps to ;
1.
2.
3.
4.
Minimize guess-work on dose
Be more effective in preventing cross-contamination
Predict frequency/timing of routine water turn-over
Provide triggers for non-standard dose monitoring
Moderate Impact
Strong Impact
Iron
Manganese
Nitrites (NO2-)
Hydrogen sulfide (H2S)
Sugars
from harvest wounds
Starches
Ammonia
Copper
Nickel
Cobalt
Proteins
from harvest wounds
Amino acids
UV – direct sunlight
Strong acidity (very low pH)
THE CLOROX COMPANY
Consumer Services Department
Oakland, California 94612-1888
ULTRA CLOROX® BRAND REGULAR BLEACH (EPA Reg. No. 5813-50)
5 gal
sales unit
Recommended
Use Rates
• 5% liquid bleach
• 12% Agricultural bleach
• 65% Hypochlorite tablets
http://www.leopold.iastate.edu/cool_tools/wash_statio
ns
• Fast Spot Checking
• Simple “Dip & Read” 1 Step
• Colorimetric Analysis
• Visual Reading
• Low Cost
Not
Total Chlorine
High Range
Typical 25-50 ppm
Low Range
Method A
1. Handle Properly
2. Verify Use by Date

Typical Steps for Low Range Measurement
 Fill sample cup
 Measure immediately
 Dip for 10 sec with gentle swirl
▪ Extend dip time in cold water
 Wait for 30 sec to color-match
 Record result within 15 sec of read
Need for Certified Organic Integrity
0
15
150
300
3000
FAU = NTU
The unit of measure for water clarity (dissolved and suspended solids)
In this test it should be
reading 3 ppm
• Chemical Test Kit
o Titration – visually read
o Colorimetric
 Visual
 Hand-held devices
• Portable ORP and pH Meters
• In-line Sensors
o Measure
o Record
o Control
Relationship between ORP and ppm in Low Turbidity Water
950
Approx. $150.00
ORP (mV)
850
750
pH 6
pH 7
650
pH 8
550
pH 9
450
350
0.5
Approx. $750.00
2
10
20
40
80
100
Measured Free Chlorine (ppm)
E. coli Salmonella Molds
Listeria
950
850
Tough Molds
Common Free Cl
needed for control
750
ORP (mV)
pH 6
pH 7
650
pH 8
550
pH 9
450
350
0.5
2
10
20
40
80
Measured Free Chlorine (ppm)
100
TIME OF
CONTACT IS
IMPORTANT
• Oxidizer 2.5x “more effective” than
•
•
•
•
chlorine (more killing)
No formation of by-products
Effective at wide pH ranges
Regulated dose limitations (3-5ppm)
Requires potable rinse (<0.8 ppm)
Small farm hydrocooler
Peroxyacetic Acid Sanitizers

Approved as water treatment

May require post-treatment rinse

Approved for all food-contact surfaces

Mode of Action:
▪ Causes oxidation of cellular constituents
▪ Metabolic “poison” …cell death appears
to continue in storage
Hydrogen Peroxide:..........................23.0%
Peroxyacetic Acid:..............................5.3%
INERT INGREDIENTS:........................71.7%
Dose volumes provided in the charts are calculated to
achieve practical ppm (parts per million) of 100%
peroxyacetic acid based on labeled percent composition
Trevor Suslow
Extension Research Specialist
UC Davis - Department of Plant Sciences
[email protected]
Wash
Water
Basin
or Tank
(gallons)
Target Dose
(values are fully-rounded* ounces of SaniDate 5.0/tank working volume)
20
30
( Common
treatment for
ag-chemical
spray tanks)
40
50
60
(Common
wash
water
dose)
85
Maximum
label dose
5
10
25
0.3
0.5
1.5
0.5
0.75
2.0
0.75
1.0
2.0
1.0
1.25
2.5
1.25
1.75
3.0
1.5
2.0
4.0
50
100
2.5
5.0
3.0
6.0
4.0
8.0
5.0
9.0
5.5
11.0
8.0
16.0
* For simplicity in measuring, the volumes to be added to the tank mix are rounded-up to an even number.
The values provided are not intended to achieve a precise dose but, rather, make routine additions on smallfarm and packing facility operations easy and reproducible.
Wash
Water
Basin
or Tank
(gallons)
Target Dose
(values are milliliters of SaniDate 5.0/tank working volume)
20
30
( Common
treatment for
ag-chemical
spray tanks)
40
50
60
(Common
wash water
dose)
85
Maximum
label dose
5
10
25
50
8
15
35
70
10
18
42
80
12
21
53
110
14
27
70
135
16
30
85
160
24
45
115
230
100
140
160
215
270
325
460
* For simplicity in measuring, the volumes to be added to the tank mix are rounded-up to an
even number. The values provided are not intended to achieve a precise dose but, rather, make
routine additions on small-farm and packing facility operations easy and reproducible.
Perceived disadvantages
•
Unit cost is higher than sodium hypochlorite
• In reality, requires complex comparisons
•
Will cause injury to some tender commodities
• Typically a problem of infrequent water turn-over
•
Pungent odor and irritation at higher doses
• Generally only with high aerosolization
Lactic Acid & Phosphoric Acid
• Needs adequate contact time
• Combined with plant extract
surfactants
Not all state Department of Public Health will ignore this discrepancy
Keystone Antimicrobial Fruit &
Vegetable Treatment
All components are Generally Recognized As Safe (GRAS)
or have been cleared by the FDA for the intended use in
a no-rinse application.
Keystone Antimicrobial Fruit &
Vegetable Treatment
Keystone Antimicrobial Fruit & Vegetable
Treatment reduces 99.9% of the pathogens E.
coli, Listeria and Salmonella* in produce wash
or process water.** EPA Reg. No. 1677-234.
Not approved for use in CA.
Active Ingredients: Dodecylbenzenesulfonic
acid, sodium salt 1.23% Lactic Acid 17.29%
Other Ingredients:.... 81.48% Total: 100.00%
Add to washing/processing vessel according to
the table submerge and agitate fruits and
vegetables for a minimum of 90 seconds. Drain
thoroughly and allow to air dry. No rinse
required.
370 Wabasha Street N St. Paul, MN 55102
www.ecolab.com 1 800 35 CLEAN
 Highly effective oxidizer
 No residue concerns
 converts to Oxygen
 Negligible DBP’s
 Kills pathogens Cl doesn’t
Evaluation of “LIQUID OZONE” for
Spray-Wash Disinfection of Avocados
CAS number
%
Mineral Oxychlorides 1332-17-8
Calcium carbonate
471-34-1
Calcium dihydroxide 1305-62-0
9-11
0.1-0.3
0.1-0.3
Bacterial populations (log CFU/cm2)
Treatment (45 sec)
Total plate count
(n=10)
Untreated
39 ppm HOCl
33 ppm PAA
JC 9450
65˚C water
2.91 ± 0.47
2.63 ± 0.88
2.75 ± 0.63
1.63 ± 1.07
2.27 ± 0.35
A
A
A
B
AB
Total coliforms
0.02 ± 0.34
0.68 ± 1.04
-0.22 ± 0.29
-0.34 ± 0.00
-0.02 ± 0.37
AB
A
B
B
B
Enterobacteriaceae
0.58 ± 0.45
0.58 ± 0.71
-0.22 ± 0.31
-0.34 ± 0.00
0.26 ± 0.51
LOD = -0.34 log CFU/cm2
*Differing capital letters refer to significant differences between bacterial counts in a
column.
A
A
BC
C
AB

Water that will be in contact with raw
food is likely to become a vehicle to
distribute microbial pathogens if a
sanitization strategy is not applied

There is not a perfect water sanitizer!

Define the objective of the water antimicrobial
program to achieve microbial reduction
objectives FOR YOUR SYSTEM
Nuh-Uh…some
guy on Twitter
says you are
soooo wrong