1 chill chain management and shelf life optimisation...

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National Technical University of AthensNational Technical University of Athens, , School of Chemical EngineeringSchool of Chemical EngineeringLaboratory of Food Chemistry & TechnologyLaboratory of Food Chemistry & Technology

Chill Chain Management and Shelf Life Optimisation Chill Chain Management and Shelf Life Optimisation of MAP of MAP SeabreamSeabream Fillets:Fillets:

A TTI Based Alternative to FIFO A TTI Based Alternative to FIFO

Petros Taoukis, Theofania Tsironi, Eleni Gogou, Marianna GiannogPetros Taoukis, Theofania Tsironi, Eleni Gogou, Marianna Giannogloulou

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Chill Chain Chill Chain –– Need for better managementNeed for better management

It is generally recognized by the European industry, retailers, It is generally recognized by the European industry, retailers, food authorities and even consumers that the weakest link that food authorities and even consumers that the weakest link that affects directly safety and quality of chilled products is the affects directly safety and quality of chilled products is the actual actual chill chainchill chain. A big percentage of . A big percentage of foodbornefoodborne disease is due to disease is due to temperature abuse.temperature abuse.

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Chill Chain Chill Chain –– Need for better managementNeed for better management

Application of an optimized quality and safety assurance system Application of an optimized quality and safety assurance system for chilled distribution of fresh chilled products requires for chilled distribution of fresh chilled products requires continuous monitoring and control of storage conditions from continuous monitoring and control of storage conditions from production to consumption. The systematic management of the production to consumption. The systematic management of the chill chain and the improved evaluation of safety, quality and schill chain and the improved evaluation of safety, quality and shelf helf life of the products can lead to reduced safety risk and increaslife of the products can lead to reduced safety risk and increased ed quality, with a significant health and economic impact to the quality, with a significant health and economic impact to the society and the market.society and the market.

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Chill chain: Monitoring andChill chain: Monitoring and ManagementManagement

Producer

Consumer

Packer/Processor

Wholesaler

RetailerHospital

Schools...

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S M A S

Development and application of a TTI based Safety Monitoring Development and application of a TTI based Safety Monitoring and Assurance System for Chilled Meat Productsand Assurance System for Chilled Meat Products

A European Commission Research and Technology Development ProjecA European Commission Research and Technology Development Projectt

Quality of life and management of living resourcesQuality of life and management of living resources

http://http://smas.chemeng.ntua.grsmas.chemeng.ntua.gr

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What is SMAS?

SMAS is an integrated chill chain management system, expected to lead to an optimised handling of products in terms of both safety and quality. It is based on the ability to continuously monitor the storage conditions of each product with the use of Time Temperature Integrators (TTI).

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The SMAS project The acronym SMAS summarizes the long title of the 3 year (2003-2006) action project “Development and application of a TTI based Safety Monitoring and Assurance System for Chilled Meat Products”, funded by the EC and co-ordinated by the National Technical University of Athens (NTUA). The project basis consisted of validated predictive models of predominant meat microorganisms growth and kinetics of the response of selected TTI, all applied in an expanded TTI application scheme that translates TTI response to meat microbiological and quality status. The ultimate purpose was to deliver an effective chill chain decision and management tool.

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OVERALL OBJECTIVE

State of the art ofTTI technology + PM and QMRA

⇓Development of SMAS, an effective and reliable quality optimization management system for products, extending from production to the

table of consumer

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Current practice: First In- First Out (FIFO)Disadvantages:ü ignores variations of product characteristicsü ignores the REAL time-temperature history of the product

Proposed practice: SMASMain Advantages:üvariations of product characteristics are consideredüthe REAL time-temperature history of the product is taken into account based on TTI response

School of Chemical EngineeringNational Technical University of Athens, Greece

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TThhee ccoonnttrriibbuuttiioonn ooff SSMMAASS iinn tthhee cchhiillll cchhaaiinn mmaannaaggeemmeenntt ccaann bbee vviissuuaalliizzeedd aass aa mmiinniimmiizzaattiioonn ooff rriisskk ffoorr iillllnneessss aanndd ooppttiimmiissaattiioonn ooff tthhee pprroodduucctt qquuaalliittyy aatt tthhee ttiimmee ooff ccoonnssuummppttiioonn

School of Chemical EngineeringNational Technical University of Athens, Greece

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TasksTasks

ØØ Study of Study of the temperature conditions in the chill chain the temperature conditions in the chill chain

(fluctuations during transport/storage, variability within (fluctuations during transport/storage, variability within the domestic equipment)the domestic equipment)

ØØCorrelationCorrelation of temperature handling to food quality with the use of temperature handling to food quality with the use

of of Time Temperature IndicatorsTime Temperature Indicators

ØØ Validation of the Validation of the Safety Monitoring and Assurance System (SMAS) Safety Monitoring and Assurance System (SMAS)

by simulation and experiment by simulation and experiment

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CHARACTERISTICS OF THE ACTUAL CHILL CHAIN

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Temperature conditions FROM production TO the retail outlet

Conclusions from survey (1)

• Sharp (but short) increases of temperature (during transport)• Cases of retail storage at temperatures > 7°C• Significant temperature fluctuations

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Survey for temperature conditions (2)

Electronic dataloggers

4 data loggers were distributed randomly to potential consumers to monitor variations

INSIDE the refrigerator

2st stage of the survey:

Variations WITHIN the domestic refrigerator

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2

3

4 1: upper shelf2: middle shelf3: lower shelf4: door

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% o

f dom

estic

refr

iger

ator

s

26%

28%

23%

15%

8%

< 4°C4°C<T< 6°C6°C<T< 8°C8°C<T< 10°C10°C<T< 12°C

Average temperature of domestic refrigerators(~400 cases)

Temperature variation within domestic refrigerators

05

1015202530

-2.0-0.80.31.52.73.85.06.27.38.59.710.812.0

upper shelf middle shelf

lower shelf door

Temperature (°C)

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Temperature variationsin distribution and storage conditions

Justification for continuous monitoringTTI

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TTI PRINCIPLES &

APPLICATION

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TTI: main principlesTime Temperature Integrators (TTI) are simple, inexpensive devices that can show an easily measurable, time and temperature dependent change that cumulatively indicates the time-temperature history of the product from the point of manufacture to the consumer, allowing the location and the improvement of the critical points of the chill chain

TYPES OF TTI

ENZYMATIC Polymer basedDiffusion based

Microbial

Photochemical

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?? : measurable change of : measurable change of ??????

Response Response functionfunction:

F(X) = k t

TTI RESPONSE KINETICS

Temperature dependenceTemperature dependence -- expressed by expressed by EaEa( ) t

11

−

−==

ref

aI TTR

EexpkktXF I

ref

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Measurement of the??? response

F(X)

Teff

Teff

f (A)

AtQuality at time t

Response function:

Quality function

( ) tTTR

EexpkAf

refeff

aAt ref

11

−

−=

( )

I

ref

a

I

t

refeff E

kXF

lnR

TT

−= −−

11

Iref aI Ek , aA Ekref

,? a (? ? ?) = ? a (food)

TTI Application scheme

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Integrated Approach to enable Traceability of the Cold chain of Integrated Approach to enable Traceability of the Cold chain of Fresh Fresh Chilled Meat and Fish Products by means of tailorChilled Meat and Fish Products by means of tailor--made made

Time/Temperature IndicatorsTime/Temperature Indicators

http://http://www.freshlabelwww.freshlabel/net/net

FRESHLABELFRESHLABEL

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Shelf life study of gilthead Shelf life study of gilthead seabreamseabream fillets packed under fillets packed under

modified atmospheremodified atmosphere

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§§ The limited and variable shelf life of chilled fish The limited and variable shelf life of chilled fish products is a major problem for their quality products is a major problem for their quality assurance and commercial viability. assurance and commercial viability.

§§ Products like chilled fillets from marine cultured Products like chilled fillets from marine cultured Mediterranean fish such as gilthead Mediterranean fish such as gilthead seabreamseabreamhave high commercial potential if their shelf life have high commercial potential if their shelf life can be extended through packaging or minimal can be extended through packaging or minimal processing. processing.

Gilthead Gilthead seabreamseabream filletsfillets ((SparusSparus aurataaurata))

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Marine cultured gilthead seabream fillets were MA packed and stored at controlled isothermal conditions 0, 5, 10 and 15°C


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Modified atmosphere packagingModified atmosphere packagingGas headspace analysisGas headspace analysis

CheckMateCheckMate 9900 O9900 O22/CO/CO22 devicedevice(Boss NT42N, Bad Homburg, Germany)(Boss NT42N, Bad Homburg, Germany)

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Microbiological analysisMicrobiological analysis§§ Total viable countTotal viable count§§ PseudomonasPseudomonas sppspp..§§ Lactic acid bacteriaLactic acid bacteria

pH measurementpH measurementSensory evaluationSensory evaluation

§§ Sensory panel of 8Sensory panel of 8§§ Rating on a 1Rating on a 1--9 descriptive hedonic scale9 descriptive hedonic scale

AppearanceAppearanceOdourOdourFreshnessFreshnessTextureTextureTasteTaste

The microbial growth was modeled using the The microbial growth was modeled using the BaranyiBaranyi Growth ModelGrowth Model

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-- Samples were stored under non isothermal conditionsSamples were stored under non isothermal conditions

§§ ScenarioScenario 1:1:TTeffeff =5.4=5.4°°C C

TTeffeff =9.4=9.4°°C C

Validation of the developed kinetic models under dynamic Validation of the developed kinetic models under dynamic temperature conditionstemperature conditions

Temperature profiles were obtained from electronic data loggers (COX TRACERTM, Belmont, NC)

1

3

5

7

9

0 10 20 30 40 50Time (h)

T(°

C)3

5

7

9

11

13

0 10 20 30Time (h)

T(°

C)

§§ ScenarioScenario 2:2:

99°°C, 4hC, 4h55°°C, 3hC, 3h

22°°C, 2hC, 2h

99°°C, 2hC, 2h1212°°C, 3hC, 3h

55°°C, 2hC, 2h

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§§ Marine cultured gilthead Marine cultured gilthead seabreamseabream fillets were MA packed and fillets were MA packed and stored at controlled isothermal conditions 0, 5, 10 and 15stored at controlled isothermal conditions 0, 5, 10 and 15°°C.C.

§§ 220% CO0% CO22 -- 8800% % airair§§ 550% CO0% CO22 -- 5500% % airair§§ 880% CO0% CO22 -- 2200% % airair


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Gas headspace changesGas headspace changes ((COCO22 andand OO22)) in fish fillet packagesin fish fillet packages

50% CO50% CO22--50% 50% airair

02468

1012

0 100 200 300 400 500 600?????? (h)

%O

2

0C5C10C15C

45

50

55

60

65

0 100 200 300 400 500 600?????? (h)

%CO

2

0C5C10C15C

Time (h) Time (h)

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Microbial growth on chilled gilthead Microbial growth on chilled gilthead seabreamseabream fillets packed under fillets packed under MA 5MA 50% 0% COCO22 atat 0, 5, 10 and 150, 5, 10 and 15°°CC

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5

6

7

8

9

0 100 200 300 400 500 600?????? (h)

logC

FU/g

0°C5°C10°C15°C

Total viable countTotal viable count PseudomonasPseudomonas sp.sp.

Lactic acid bacteriaLactic acid bacteria

3

4

5

6

7

8

0 100 200 300 400 500 600?????? (h)

logC

FU/g

0°C5°C10°C15°C

3

4

5

6

0 100 200 300 400 500 600?????? (h)

logC

FU/g

0°C5°C10°C15°C

Time (h) Time (h)

Time (h)

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Specific growth ratesSpecific growth rates k k ((hh--11)) and kinetic parameters of lactic acid and kinetic parameters of lactic acid bacteria in MAP (50% CObacteria in MAP (50% CO22 –– 50% air)50% air)

1515°°CC

1010°°CC

55°°CC

00°°CC

??

0.00.028292829

0.00.019251925

0.00.010781078

0.000.00342342

k (hk (h--11))

EEaa= = 9911 kJ/molkJ/mol

kkref(4ref(4ººC)C)=0.0=0.007390739 hh--11

RR22=0.9=0.94747

−+=

T1

T1

RElnklnk

ref

aref

Arrhenius equation

-6

-5

-4

-3

-0.0001 0 0.0001 0.00021/Tref-1/T

lnk

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Predicted (Predicted (SLSLpredpred) and experimental shelf life () and experimental shelf life (SPSPexpexp) of MAP ) of MAP gilthead gilthead seabreamseabream fillets under fillets under nonisothermalnonisothermal conditionsconditions

--1.01.0

233233

235235

5050% CO% CO22

% % errorerror

SLSLexpexp (h)(h)SLSLpredpred (h)(h)

ScenarioScenario 11

--12.812.8

112112

127127

5050% CO% CO22

% % errorerror

SLSLexpexp (h)(h)SLSLpredpred (h)(h)

ScenarioScenario 22

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3

5

7

9

0 10 20 30 40 50Time (h)

T(°

C)3

5

7

9

11

13

0 10 20 30Time (h)

T(°

C)

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Shelf life evaluation of gilthead sea bream Shelf life evaluation of gilthead sea bream stored in MAP (50% COstored in MAP (50% CO22))

82 (3 d)76 (3 d)15°C

140 (6 d)129 (5 d)10°C

301 (12 d)268 (11 d)5°C

563 (23 d)612 (25 d)0°C

Shelf life (h) evaluated by sensory analysis

(total impression>5)

Shelf life (h) evaluated bymicrobiological growth

(lactic acid bacteria <6 logCFU/g)

Storage temperature

EEaa= 85.5 kJ/mol= 85.5 kJ/molEEaa= 90.8 kJ/mol= 90.8 kJ/mol

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Application of the ArrheniusApplication of the Arrhenius--type model for shelf life prediction of type model for shelf life prediction of chilled gilthead chilled gilthead seabreamseabream fillets under MAPfillets under MAP

−

−=

T1

T1

REexp

COCOCOkk

ref

a

2max

22maxref

% CO% CO2 2 concentrationconcentrationTemperatureTemperature ?? Shelf lifeShelf life

Limit:Limit: 101066 for LABfor LAB**

2828 dd1818 dd1313 dd1010 dd99 dd77 dd66 dd55°°CC

6161 dd4040 dd2929 dd2323 dd1919 dd1616 dd1414 dd00°°CC

80%80%70%70%60%60%50%50%40%40%30%30%20%20%TT

COCO22 concentrationconcentration

** Based on Based on organolepticorganoleptic acceptability the end of shelf life coincided with 10acceptability the end of shelf life coincided with 1066 LAB for MAP stored samples.LAB for MAP stored samples.

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Application of the ArrheniusApplication of the Arrhenius--type model for shelf life prediction of type model for shelf life prediction of chilled gilthead chilled gilthead seabreamseabream fillets under MAPfillets under MAP

0

200

400

600

800

1000

1200

1400

0 2 4 6 8 10 12 14 16

Temperature (°C)

Shel

f lif

e (h

)aerobically packed

? ? ? (20% CO2)

? ? ? (30% CO2)

? ? ? (40% CO2)

? ? ? (50% CO2)

? ? ? (60% CO2)

? ? ? (70% CO2)

? ? ? (80% CO2)

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Kinetic Study of the Kinetic Study of the

TTIsTTIs

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OnVu TTIs are based on the inherent reproducibility of reactions in crystal phase

TTI Color reference scale

Photosensitive compounds are excited and coloured by exposure at UV radiation

The coloured state reverses to the initial colorless at a temperature depended rate

Photochemical TTI

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TTI testing

•TTIs were activated and studied at several charging times

Inactivated TTI Hand charger use Activated TTI

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Instrumental measurement of TTI colour

X-rite Eye1pro Colorimeter

Illumination D50Measurement of visual response with CIE Lab

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TTI Response KineticsTTI Response Kinetics

oo ResponseResponse functionfunction:

( ) t 11

−

−==

ref

aI TTR

EexpkktXF I

ref

( ) ( )[ ] tdTTR

EexpkdttTkXF

t

ref

aI

t

tI

ref ∫∫

−

−==

00

11

oo ForFor variablevariable temperature distribution:temperature distribution:

oo UsingUsing effective temperature:effective temperature:

( ) tTTR

EexpkXF

refeff

aIt

I

ref

−

−=

11

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Instrumental measurement of TTI colour

0

10

20

30

40

50

60

70

80

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00

t (h)

L

-12

-10

-8

-6

-4

-2

0

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00t (h)

a

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00t (h)

b

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Response function

kt

EE −=

∆∆

exp0

2max

2min

2max )()aa()( bbLLE −+−+−=∆

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B1 TTI response modelling

TTI Activation: UV lamp exposure for 1 seconds

168,28168,280,00610,00613.53.5

204,01204,010,00500,00502.52.5

126,40126,400,00810,008155

20,2420,240,05040,05041515

49,7749,770,02050,02051010

71,9771,970,01420,014288

332,17332,170,00310,003100

Shelf lifeShelf life(hours)(hours)

Rate Rate k (hk (h--11))

Storage Storage temperature temperature

((ooCC))

0

5

10

15

20

25

30

35

40

45

0 100 200 300 400 500t (h)

DE

mod

el

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44


TTI Activation: UV lamp exposure for 2 seconds


05

101520253035404550

0 50 100 150 200 250 300t (h)

DE

mod

el

327,27327,270,00370,00373.53.5

396,75396,750,00310,00312.52.5

245,82245,820,00490,004955

39,3639,360,03080,03081515

96,7996,790,01250,01251010

139,96139,960,00870,008788

645,98645,980,00190,001900


Rate Rate k (hk (h--11))

Storage Storage temperature temperature

((ooCC))

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B1 TTI response modellingEa=116KJ/mol

TTI Activation: UV lamp exposure for 2s

-6,000

-5,500

-5,000

-4,500

-4,000

-1,0E-04 -8,0E-05 -6,0E-05 -4,0E-05 -2,0E-05 0,0E+00 2,0E-05

1/T-1/Tref

lnk

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Dependence of response rate on charging time

435.18435.180,00330,003333

297.39297.390,00380,003822

576.13576.130,00300,003044

1625.521625.520,00100,00101515

1177.881177.880,00160,00161010

789.42789.420,00240,002466

152.92152.920,00640,006411


Rate Rate krefkref (h(h--1)1)

Charging time Charging time (s)(s)

0,000

0,001

0,002

0,003

0,004

0,005

0,006

0,007

0 5 10 15tc(s)

kref

(h-1

)

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47



0.00

240.00

480.00

720.00

960.00

1200.00

1440.00

1680.00

1920.00

0 2 4 6 8 1 0 1 2 14 16Temperature (°C)

She

lf lif

e (h

)

1 second ch.t.

2 seconds ch.t.3 seconds ch.t.4 seconds ch.t.6 seconds ch.t.10 seconds ch.t.15 seconds ch.t.

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0

100

200

300

400

500

600

700

0 5 10 15Storage Temperature (°C)

She

lf li

fe (h

)gilthead seabream fillets stored in MAP (50% CO2)TTI 2.3s

Ciba Ciba OnVuOnVu HandchargerHandcharger

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Field Test DesignField Test Design

80 samples of MAP gilthead seabream

fillets

LaboratoryLaboratorysimulatedsimulatedconditionsconditions

Distribution centerDistribution center(decision point)(decision point)

Local marketLocal market

Export marketExport marketconsumersconsumers

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2nd step72 h at various T conditions

TTIbased split

Decision pointTTIs reading

Microbiological analysis4th step

Field test Design

80 packages

1st step

40 PackagesTTI tag

attached on each package

40 packages without TTIs

3rdst

ep

Local market

4oC

8oC72, 96 hours

Export market

4oC

8oC144, 168 hours

0

3

6

9

12

15

0 12 24 36 48 60 72Time (hours)

Stor

age

tem

pera

ture

(oC

)

t-T profil1

t-T profil2

t-T profil4

0

3

6

9

12

15

0 12 24 36 48 60 72Time (hours)

Stor

age

tem

pera

ture

(oC

)

t-T profil3

t-T profil5

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Ä After 72 hours TTI bearing products were split according to the TTI color readings, using the 16-stage color scale

Ä FIFO samples were split randomly

TTI readings at the time of decision

color reference scale

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

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1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

3

Sample stored for 72h at Teff=2.3oC(photo taken at the time of split)

1

T-t profil_1

0,0

1,0

2,0

3,0

4,0

5,0

6,0

0 12 24 36 48 60 72

Time (hours)

Stor

age

Tempe

ratu

re

(o C) Time Temperature Profil 1

Teff=2.3oC


1st group of 8 samples

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53


1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

5


1

T-t profil_2

0123456789

10

0 12 24 36 48 60 72

Time (hours)

Stor

age

Tempe

ratu

re

(o C

) Time Temperature Profil 2

Teff=4.4oC


2nd group of 8 samples

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54


1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

8


1

T-t profil_3

0

2

4

6

8

10

12

14

0 12 24 36 48 60 72

Time (hours)

Stor

age

Tempe

ratu

re

(o C

)

Time Temperature Profil 3

Teff=8.0oC


3rd group of 8 samples

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55


1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

T-t profil_4

0

2

4

6

8

10

12

14

0 12 24 36 48 60 72

Time (hours)

Stor

age

Tempe

ratu

re

(o C

)

10


1


Teff=9.7oC


4th group of 8 samples

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56


1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 1615


1

T-t profil_5

0

2

4

6

8

10

12

14

0 12 24 36 48 60 72

Time (hours)

Stor

age

Tempe

ratu

re

(o C

)


Teff=11.8oC


5th group of 8 samples

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TTI Based Split-Analysis TimetableAfter the TTI color readings all TTI bearing products:

Äare sorted according to their temperature history

ÄSPLIT into 2 subgroups: the 20 more temperature abused belong to ‘Products for local market’, the rest of them belong to ‘Products for distant market’

ÄBoth groups (local & export) are stored in two temperature cabinets (4,8oC)

ÄThe microbiological analysis timetable

144h168h96h72ht4t3t2t1

Export MarketLocal Market

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Time-Temperature profiles for the TTI bearing products throughout the field test

0

3

6

9

12

15

0 50 100 150 200 250 300

Time (h)

Sto

rage

tem

pera

ture

(oC

)

S11S12S13S14S15S16S17S18S19S20

0

3

6

9

12

15

0 50 100 150 200 250 300

Time (h)

Sto

rage

tem

pera

ture

(oC

)

S1S2S3S4S5S6S7S8S9S10

0

3

6

9

12

15

0 50 100 150 200 250 300

Time (h)

Stor

age

tempe

ratu

re (oC

)

S21S22S23S24S25S26S27S28S29S30

0

3

6

9

12

15

0 50 100 150 200 250 300

Time (h)

Sto

rage

tem

pera

ture

(oC

)

S31S32S33S34S35S36S37S38S39S40

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0

2

4

6

8

10

12

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 2021 22 23 24 25 26 27 2829 30 31 32 33 34 35 3637 38 39 40sample

Effe

ctive

Tem

pera

ture

(o C

)

72 hours 96 hours 144 hours 168 hours

72 hours

Effective temperature for all FIFO handled products at the time of “consumption”

Effective temperature for all TTI bearing products at the time of “consumption”

TTI sorting resulted in promoting the more temperature abused products to be “consumed” first

FIFO handled products……

96 hours144 hours

168 hours

0

2

4

6

8

10

12

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 2021 22 23 2425 26 2728 29 30 31 32 33 34 3536 37 3839 40

sample

Effe

ctive

Tem

pera

ture

(o C

)

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FIELD TEST RESULTSCalculated microbial log counts for each date of microbiological analysis show the different distribution of microbial load in the 2 groups

012345678

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Samples

Lac

tic

acid

bac

teri

a lo

g co

unts

.

FIFO handled productsTTI bearing products

72 hours after split 96 hours after split 144 hours after split 168 hours after split

Spoilage level=log6

61

61


Distribution of Lactic acid bacteria growth for all samples at time ofmicrobiological analysis - time of ‘consumption’.

FIELD TEST RESULTS

Spoiled products

The distribution of microbiologicalgrowth moves to the left, to lower

values, for the TTI bearing products

0

10

20

30

40

50

60

log3-log4 log4-log5 log5-log6 log6-log7 >log7

Lactic acid bacteria log counts

% o

f sam

ples

FIFO handled products

TTI bearing products

62

62


Validation of the developed model of the Validation of the developed model of the TTI response value (TTI response value (? ?? ?))

Predicted vs. observed TTI Predicted vs. observed TTI response values at the time of splitresponse values at the time of split

0

5

10

15

20

25

30

35

40

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 242526 272829 30 31 3233 343536 37 3839 40

sample

?? (TTI

resp

onse

value

)

observed

predicted

63

63


Predicted vs. observed LAB counts Predicted vs. observed LAB counts for all for all 8080 samples used in the samples used in the

field testfield test

2.0

3.0

4.0

5.0

6.0

7.0

8.0

2.0 3.0 4.0 5.0 6.0 7.0 8.0(logcfu/g)observed

(lo

gcf

u/g

)pre

dic

ted

Validation of the developed model of Validation of the developed model of Lactic Acid Bacteria growthLactic Acid Bacteria growth

64

64


Thank you for your attentionThank you for your attention!!

This study was supported by the European Commission FP6 CollectiThis study was supported by the European Commission FP6 Collective Research ve Research Project COLLProject COLL--CTCT--20052005--012371 (http://012371 (http://www.freshlabelwww.freshlabel/net)/net)

1 chill chain management and shelf life optimisation...

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