MRE Rations in All-Polymeric Pouches
and why would we want to go there!
Tom Dunn
Printpack Inc.
Atlanta, Ga
Why do we wanna go there?
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Look at current MRE packaging
Really look at current MRE packaging!
Look at current MRE logistics
Consider novel food processing techniques
Assess their impact on packaging requirements
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Identify critical success factors for this packaging
Consider alternatives for achieving this mission!
Review results to date
Anticipate future development
A look at current MRE packaging
He that will not apply new
remedies must expect new evils;
for time is the greatest innovator.
Things alter for the worse
spontaneously,
if they be not altered for the better
designedly.
~Francis Bacon
Really look at current MRE packaging
Foil Pouch Lamination: Entrees
Oriented PET
Aluminum Foil
Puncture Resistance,
Heat resistance
Light, Oxygen, Water
Vapor Barrier/ Stiffness
Oriented BON
Puncture Resistance
Polyolefin
Pouch Sealing / shock
absorbance
MRE Logistics
Process
Packaging
Store
Transport
Store
Deploy
120
100%
90%
80%
70%
80
60%
RH
Degrees F
100
60
50%
40%
40
30%
20%
20
10%
0
0%
1 2 3 4 5 6 7 8 9101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990
Weeks in Storage
TEMP
RH
Novel Food Processes: Impact Factors
Minutes @
121ºC
PRESSURE (psi)
Retort
~40-50
13
Commercial
MWS
~5
35
Developmental
PATS
~5
100,000
Developmental
HPP
Max: ~40100ºC
70,000
Commercial
eHPP
Max: ~40100ºC
150,000
Research
PROCESS
STATUS
Process/Packaging Impact
PROCESS
PACKAGING IMPACT
Retort
High thermal stability
MWS
Thermal stability; microwave transparency
PATS
low volatiles; conformable; thermal stability;
HPP
low volatiles; conformable
eHPP
low volatiles; conformable; tbd
Process/Logistics Impact
PROCESS
LOGISTICS IMPACT
Retort
MWS
PATS
HPP
eHPP
Adapt the Packaging!
Adapt the packaging to microwave sterilization!
PROCESS
MWS
Packaging Success Factors
Microwave transparent
Light barrier
Oxygen barrier
Water vapor barrier
Resistant to transient high temperatures
Stiffness
Weight
Plan of Attack: Packaging for MWS
FACTOR
OBJECTIVE
MW
transparent
Non-foil and ?
Light
100% Opaque or ?
Oxygen
NSRDEC 0.01 cc-day/100 sq. in./atmosphere or ?
Water vapor
NSRDEC 0.06 gm-day/100 sq. in./atmosphere or ?
Temp Resist 121ºC for 7 minutes
Stiffness
Equal to foil pouch
Weight
Equal to/less than foil pouch
Cost
Equal to/less than foil pouch
Other
Burst, puncture resistance, etc. equal to/greater than
foil pouch
Tactics
OBJECTIVE
APPROACH
MW transparent
Develop assessment method; assess candidates
Light
Determine scope of need; assess candidates
Oxygen
NSRDEC target
Water vapor
NSRDEC target
Temp Resist
Familiar polymers (heat set & melting point)
Stiffness
oriented films with modulus ~ foil
Weight
Familiar polymers with density less than foil
Cost
Map territory around above targets
Other
Familiar polymers
Light Barrier Results
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Virginia Tech review of photodegradation chemistry of MRE foods
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Virginia Tech development of lab model to assess light barrier
effectiveness
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Olive oil and yogurt as model foods
Hexanal as target indicator
Link hexanal generation to UV-Vis light absorption of packaging materials
Design light barrier in packaging materials
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Organoleptic and nutritional values at risk
Wide spectrum (UV-visible light) of active harmful light energy
Opacified polymer layer(s)
Opacified adhesive layer(s)
Confirm effectiveness with accelerated shelf life assessments
Microwave Transparency Results
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WSU adapted dielectric properties food method to flexible packaging
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e’: ability of a material to store electromagnetic energy
e“: ability of a material to dissipate electric energy as heat
Carbon black
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Limited FDA food-contact approval
Known microwave absorption
Figure A: Dielectric properties
0.035
0.03
Carbon Black
Carbon Black
Clear
1 opaque
adhesive
0.025
0.02
Loss Factor
0.015
0.01
0.005
0
2.55
2.6
2.65
2.7
2.75
2.8
2.85
Dielectric Constant
2.9
2.95
3
3.05
Oxygen Barrier Results
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Limited success with nanocomposites and multilayer coextrusions
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Nanocomposites couple with MV energy
Coextrusions will play a role. (machine/material complexities slow down)
Available films and polymers have weaknesses
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Moisture sensitivity
Coating durability
Water Vapor Barrier Results
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Simple polyolefins best MVTR providers
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Strong thickness impact
Coatings the other alternative
High Barrier WVTR Coating durability issue
“Saran” Coating presents environmental negatives
Other Results
Temp Resist
Same polymers inside and out
Stiffness
All comparable to foil
Weight
All less than foil
Cost
Trade offs with respect to performance
Other
Comparable burst, puncture, etc
Pouch laminations: Foil v. Polymeric
Barrier Coating
Oriented PET
Oriented PET
Aluminum Foil
Coated PET
Oriented BON
Coated BON
Polyolefin
Polyolefin
Pouch laminations: Foil v. Polymeric
Puncture Resistance,
Heat resistance
Light, Oxygen, Water
Vapor Barrier/ Stiffness
Oriented PET
Coated PET
Coated BON
Puncture Resistance
Pouch Sealing / shock
absorbance
Polyolefin
Arrive where we started and know the place for the first
time
Future Developments/Packaging
1) On-pack Time & Temperature Integrator
2) Shelf life modeling of logistics factors
 Sensitivity analysis for barrier levels
 Contribution to shelf life of secondary packaging
3) Microwave interaction with polymeric chemistry
4) Within pouch-type/between process shelf life comparisons
5) Impact of packaging on nutritional factors over time
 Cross process technology comparison
 Foil- and Polymeric- pouches comparison
6) Failure analysis: packaging volatiles during HPP
7) Definition of Quality Plan for MWS pouches
8) Technology transfer to commercial applications
Thank you for your attention!
Any questions, Now?
Later?
tdunn@printpack.com