high pressure thermal processing of foods - innova · outline • high pressure thermal processing...

Juliano | INNOVA 2013 | 7 Oct 2013 | Montevideo | Page 2

Pablo Juliano, Roman Buckow, Thambaramala Gamage, Michelle Bull, Sandra Olivier, and Kai Knoerzer

High Pressure Thermal Processing of FoodsA method to develop high quality chilled meals and shelf stable products

• CSIRO ANIMAL, FOOD AND HEALTH SCIENCES

Short Course – NPD Workshop, 15 October 2012,

Animal, Food and Health Sciences

Outline

• High pressure thermal processing – process definition• Product categories• Spore inactivation – synergies• Impact on food quality and nutrient retention• Packaging materials for HPT• Equipment and scalability• Regulatory requirements and validation of the technology• Challenges and recommendations

Juliano | INNOVA 2013 | 7 Oct 2013 | Montevideo |

HPTProcess definition and product categories

• Process conditions for HPT:– Pressures up to 600-800 MPa– Moderate initial temperature 60-90°C– Holding times up to 5 minutes

• Heat source:– Compression heating: up to pasteurisation/sterilisation temperatures (85-125°C)

• Benefits:– Rapid compression heating and decompression cooling– Bacterial spore inactivation– Synergy between pressure and temperature.

– Claim: potential to develop chilled or shelf stable foods with superior quality to retort

Basics of high pressure thermal processing

pressurepressure

temperaturetemperature

IMPROVED QUALITY

Clostridium botulinum spore

HP-35 L Sterilization Unit


HPT: processing steps

Vac, pack & load Preheating

Cooling UnloadThermal pressurisation

Juliano | INNOVA 2013 | 7 Oct 2013 | Montevideo | 5

Heater

Intensifier

Drain

Process Water

Reservoir90 CMin.

Process water overflow 90 C min.

Divert valve

Process water supply

Pre-Heater

High PressureWater

Reservoir

Heater Outlet Temperature

90C MinH

PP Pres Wall

Vessel Heater

90 C H20700MPa

Heater

Divert Valve

Pressure Chamber

Carrier Assembly

Hydrostatic PressOfficial Process

Step 2


HPT : process T- P profile

0

15

30

45

60

75

90

105

0.0 2.4 4.8 7.2 9.7 12.1 14.5 16.9 19.3Time (min)

Tem

pera

ture

(ºC

)

-90

10

110

210

310

410

510

610

710

Pres

sure

(MPa

)

Temperature

Pressure

Transfer c/o pressure vessel

Pressure onPressure off


Basics of HPT- Desired pressure/temperature profiles

Assuming no heat losses during holding and no differences in compression heating properties of all materials involved inside the chamber

600-800 MPa

60-90°C

85-125°C


Compression heating of foods

Substance Initial temperature

(°C)

Temperature change (°C/100

MPa)Water 20 2.8

60 3.880 4.4

Steel 20 ~0Chicken 20 2.9Cheese (Gouda type)

20 3.4

Milk fat 20 8.5

de Heij et al., 2003

Steel < water < other fat composed foods

water, steel, and other foods


Compression heating of insulating polymers- Adiabatic heating as function of p and T0

0 100 200 300 400 500 600 7000

20

40

60

80

100

120

140

Pressure / MPa

Tem

pera

ture

/ °C

(MPa)

(°C

)

(Knoerzer et al., 2010; Journal of Food Engineering, 98(1), 110-119)


Temperature profiles: HPT and retort

0 10 20 30 40 50 60

T HPT

T Retort

20

Temperature (ºC)

100

120

60

40

80

Time (min)

Transfer c/o pressure vessel

Pressure on

Pressure off

Preheating

Cooling

Shorter processing times

Lower temperature

Compression heating


Potential applications

• Chilled meals• Shelf stable foods• Vegetable, meats, precooked meals (MREs)

• Pharmaceutical products


http://www.survivalsuppliesaustralia.com.au/meals-ready-to-eat.php�

List of potential products

•Long life chill stable•RTE meats•Meat snacks•Vegetables

•Shelf stable•Breakfast items (eggs)•Meat joints•Pot roasts/stews•High quality soups•RTD Teas/coffees•Dairy desserts/smoothies•Cheese/cream sauces•Low acid pasta sauces•High quality fruit/vegetables•Liquid flavors/herbs


HPT: the key for success

Need to destroyPathogens Spoilage organisms

Enzymes

Optimize Flavor Texture Color

Nutrition

Processing Balance


Microbial spore inactivationSynergies between pressure and heat

High pressure hurdles for microbial safetyC

hill

stab

leAm

bient stable

High temperature

Ambient temperature

vegetative pathogens

viruses

non-proteolytic

C. botulinum

proteolytic

C. botulinum

moulds

various

vegetative pathogens


Inactivation of target C. botulinumComparison of strain resistance

0

1

2

3

4

5

6

7

8

9

Aver

age

log 1

0cf

u/g

redu

ctio

n

Non-proteolytic strains Proteolytic strainsInactivation of 29 Clostridium botulinum strains and Clostridium sporogenes PA3679 by a HPT process of 600 MPa, 1 min with a pressure-on temperature of 95°C. Spores were pressure treated in MPA3679 broth, in a laboratory-scale, multi-vessel high-pressure unit (Model U111, UnipressEquipment, Poland).

600 MPa, 1 min with a pressure-on temperature of 95°C.

Legan, Chapman, Bull. 2008, PCT/US07/88938


HPT for ESL chilled low acid foods

-5.0

-4.5

-4.0

-3.5

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0 1 2 3 4 5 6 7 8 9 10

Log 1

0re

duct

ion

(cfu

/mL)

F90°C (min)

Heat only

57.5°C 550 MPa

65°C 500 MPa

65°C 600 MPa

72.5°C 450 MPa

72.5°C 550 MPa

72.5°C 650 MPa

80°C 500 MPa

80°C 600 MPa

87.5°C 550 MPa

Significantly less heat is required to inactivate an equivalent number of spores of

non-proteolytic Clostridium botulinum

HPP and heat could be used to extend the shelf-life of chilled low acid foods

e.g. beyond 10 day guidelines

OR

Legan, Chapman, Bull, WO2008083216-A1


Comparison of HPT vs. Thermal onlyOrganism

Bolognese sauce (30% w/w)

Cream sauce (50% w/w)

Diluted rice-based product

C. botulinum 2802 Synergistic * Synergistic *No significant

difference

C. botulinum 2803No significant

differenceNo significant


difference

C. botulinum 2804 Synergistic * Synergistic **No significant

difference

C. botulinum 2806 Synergistic *No significant


difference

C. botulinum 2807No significant



difference

C. sporogenes 2790No significant



difference

One-way ANOVA of residuals compared with heat only processing *significant at 95% ** significant at 99%

Bull et al. 2009 Applied and Environmental Microbiology 75: 434-445.


Comparison of HPT vs thermal only:spoilage spore-forming microorganisms

Mesophiles

Cream sauce Bolognese sauce

Lab-scale(diluted products)

Pilot-scale Lab-scale(diluted products)

Pilot-scale

B. amyloliquefaciens FRRB 2782 Synergistic ** Insufficient data Synergistic ** Synergistic *

B. sporothermodurans FRRB 2706 Synergistic **Obvious synergy

Synergistic ** Synergistic **

B. coagulans FRRB 2723No significant

differenceProtective**

No significant difference

Synergistic **

ThermophilesCream sauce Bolognese sauce

Lab-scale(diluted products)

Pilot-scale Lab-scale(diluted products)

Pilot-scale

G. stearothermophilus FRRB 2792 Synergistic ** Synergistic ** Synergistic ** Synergistic **

* significant at 95% ** significant at 99%Olivier et al. 2011. Appl. Environ. Microbiol. 77(7):2317-2324.


synergism at T<110°C, protection T>110°C?

Impact on food quality and nutrient retention


HPT: food quality • A few publications exist on the quality of HPT products• Foods studied using analytical methods• Broccoli juice• Green beans• Spinach• Tomato puree, juice• Meat sauce• Carrots• Red radish• Jicama

• Foods studied with sensory and consumer panels• Tomato puree• Scrambled egg patties

Matser et al. 2004; Krebbers et al. 2002, 2003; Barbosa-Cánovas and Juliano 2006; Juliano et al. 2005, 2006, 2007, 2012Leadley et al., 2008Gupta et al., 2010Nguyen et al., 2010Knoeckaert et al., 2011Vervoort et al. 2012


KEY ASPECT: DECREASE TEMPERATURE

HPT: lycopene in tomato paste

Krebbers et al., 2003

118ºC, 20 min

4 min, 72ºCRaw

LYCOPENE AND RED COLOR RETENTION

Sensory panelists preferred color from HPT tomato paste


HPT: texture on green beans

Krebbers et al. 200275ºC/1000 MPa/80s 2 pulses

MORE FRESHLIKE TEXTURE


HPT: Vit C retention

Matser et al. 2004

90ºC/700 MPa/30s; Two pulses

MORE VIT C RETAINED GREEN BEANS


HPT: aroma retention

85ºC/700 MPa/30s; Two pulses

MORE RETENTION OF AROMA

fresh basil

Matser et al. 2004


Suggested weight: 8 oz, i.e., use two 4 oz patties per pouchSuggested size shape: 4.5 x 3 inches egg patty

Egg product development

Juliano et al. 2005, J Food Quality


Natick Soldier Center

Academia Partners

Industrial Partners

American Egg Board

COMBAT RATION NETWORK FOR TECHNOLOGY IMPLEMENTATION

NCFST


Shelf stable egg products by HPHTScrambled egg patty ingredients

MixingMolding

CookingAir: 180º - 250º C

Partial Cooling

Preheating

HPT

t, T, P

Cooling

Testing

Storage5º C, 24 h

Dosing

75º C 6 to 15 min

0º C, 5 min -Steam injection-Water bath at constant T

Levels?-10 mbar-400 mbar-no vacuum

5 min75º C 700 MPa

Formulation Michael Foods

Freezing

Vacuum Packaging

Shipping (-18º C)

Defrosting(5º C, 24 h)

Optional: water addition

Process T: 105ºC


Product evaluation

• Consumer panels• Instrumental analyses• Texture: TPA analysis• Color: colorimeter, CIE Lab• Syneresis: % weight loss

Electronic booths

Juliano et al. 2005; J Food Sci, Juliano et al. 2007, J Food Quality


Egg patties overall acceptability

90ºC/20 min75ºC/20 min

690 MPa/105ºC/5 min 690 MPa/121ºC/3 min

Verified by appearance, texture, flavor/aroma descriptors form descriptive panel

No significant differences in overall acceptability

Juliano et al. 2007, Journal of Food Quality


HPHT egg patties

90ºC/20 min75ºC/20 min

690 MPa/105ºC/5 min 690 MPa/121ºC/3 min

75ºC/20 min

690 MPa/105ºC/5 min

690 MPa/121ºC/3 min

Appearance

Juliano et al. 2007, Journal of Food Quality


Packaging materials for HPT


Types of packaging materials

• Pouches • materials studied• limitations • comparison with retort pouches

Pyramid plastic pouch

Pyramid foil laminated pouch

MRE PouchSmurfit

• Trays

ToppanCompany

Japan EVOH-based

Al-based

Nippon plastic pouch

PA(nylon) -basedPVDC –MA based


General requirements for pouch acceptability


Juliano et al. 2010, Food Engineering Reviews

HPT: packaging studies

•Packaging identification is challenging• Blister formation – packaging integrity• O2/H20 permeability studies after HPT but no much

information on seal integrity and film strength

Some EVOH materials, a PA-based material, and a fewAl-based/metalized pouches showed acceptable visualintegrity after HPT.

The preheating process can affect the overall integrity of thepackage, especially when temperatures greater than 90°C are used

Juliano et al. 2010; Koutchma et al. 2009


Selected materials for HPT

Juliano et al. 2010, Food Engineering Reviews


• Typical temperature–pressure profile of a HPT process

• Oxygen and water vapour transmission rates for packaging materials before and after HPT processing

Bull et al. 2010, Innov Food Sci Emerg Technol

Selected materials for HPT


Equipment and scalability


HPT: available systems

•Laboratory scale•0.02 L - 2 L

•Pilot - Industrial scale•10 L – 17 L•At least five HP-35L units in the world

–Australia; USA (2); The Netherlands; Italy

Preheating system

Sample holder

Cooling system

HP Vessel

Pilot Scale DUST HP-35 L at Kent, WA

Compression fluid: city water

Temperature: up to 130ºCInternal heater to control temperature

Capacity-17 liters


High Pressure High Temperature equipment

• System requirements• Preheated chamber

– two or more concentric cylinders – high tensile strength pre-wounded stainless steel– outer cylinders compress the inner cylinders – equipment lifetime >100,000 cycles at 680 MPa

• Preheated compression fluid and pipes– Filtered (potable) water (recommended)– Oil or water containing FDA- and USDA-approved

lubricants– anti-corrosion agents, solutions of castor oil, silicone

oil, and sodium benzoate

• Carrier: a dense polymeric insulating liner– free moving piston at the bottom or valve to

allow adequate pressure transmission

FLOW QUINTUS® Food Press QFP 35L-600 Sterilization machine


Thermal insulation

•Liner increases heat retention efficiency

•Four type K thermocouples at top, middle high, middle low, and bottom sections

CARRIER LINER

thermocouples


Insulated carriers will be key for industrialisation

•Laboratory scale

1.7 L, EPSI,

Max: 700 MPa, 130ºC

•Pilot scale

Hiperbaric/55HT, Max 630 MPa; 90ºC

2 L QFP-6 Max: 900 MPa; 80 ºC .

Main suppliers of HPT equipment:Avure Technologies Inc, Elmhurst Research, Inc. Hiperbaric EPSI StanstedUhde High Pressure Technologies



HPP systems at CSIRO

•2 mL kinetic, (700 MPa) and temp

•300 mL, pressure (800 MPa) and temp

•2 L, pressure (500 MPa)

•3L, pressure (800 MPa) and temp

•35L, pressure (690 MPa) and temp

35 L Avure Technologies

2 mL Unipress kinetic

3L Stansted

Equipment costs and energy requirementsCommercial HPP units cost US$ 0.5–2.5 million depending upon capacity and automation level; however, higher costs are considered for HPT systems

Buckow et al. 2008; Mujica-Paz et al. 2011


Regulatory requirements and validation of the technology


Technology Application Risk (Microbial)

Regulation

PATS Ambient Stable low acid foods

Severe 21CFR113

HPP Shelf life extension (chilled foods)

Moderate GMPs only 21CFR110

HPP/PATS Ambient stable acidified foods

Moderate 21CFR114

HPP Low acid foods (sterilization)

Severe 21CFR113

Regulatory aspects

Martin Cole and Larry Keener, Natick, 2009


Regulatory aspects• FDA filing of HPT mashed potato product – Feb 2009• DUST program

Patrick Dunne, Natick, 2009

First ever petition to FDA for the commercial use of pressure-assisted thermal sterilization (PATS) processes for application in the production of low acid foods.

Natick Army Labs Sensory Work

Panel Average, Standard DeviationViewing Result Summary Statistics: T09+18A

1 2 3 4 5 6 7 8 9

APPEARANCE Quality

ODOR Quality

FLAVOR Quality

TEXTURE Quality

OVERALL Quality

MRE mashed potato, time=0

HPP mashed potato, time=0

Ratings are on 9-point

Quality scale. N = 12-15

Mean quality scores:MRE = 5.6PATS = 7.2Shown at IFT 2009EXPO Innovation Award


Generalized PATS ProcessMashed Potato

Preparation PouchFiller

VacuumSealing

Product Cage and

Carrier

Hydrostatic Press

Cooling Tank

Product Cage

Cage / Carrier Transfer 90C Minimum

Pre-heating tank

100°C Water

Official Process Step 1

Official Process Step 2

Measuring pressure and temperature

• Pressure sensors• Pressure gauge

• Temperature sensors• Type T, K thermocouples• Thermo egg

The shell• Highly stress resistant• Low specific heat capacity

• heat sink effect minimal

• High thermal conductivity

Integrity established in ~ 150 runs

0 500 1000 1500 200035

40

45

50

55

60

65

time / s

tem

pera

ture

/ ºC

thermocouple datacorrected Thermo-Egg data

0 500 1000 1500 20000

100

200

300

400

500

600

Pre

ssur

e / M

Pa

pressure

Knoerzer et al. 2011

The data logger• Temperature range

0ºC ≤ T ≤ 130ºC• Measurement intervals ≥ 1 s• Memory:

4,000 logs per run


http://www.maxim-ic.com/products/ibutton/products/ibuttons.cfm�

Temperature control (Task 1)


HPT processing- Pressure and Temperature Distribution

• Uniform pressure distribution• However: temperature

variation through the vessel caused, e.g., by heat losses to cooler walls, differences in compression heating and other material properties


Initial conditions

t = 0

Modelling HPT systemsIncluding: vessel lid, cylindrical packs, carrier bottom valve

carrier

water

• Materials:– Compression medium:

Water– Carrier: PTFE– Vessel: Structural steel– Packs: Model food

• Parameters and variables:– Pressure: 0-600 MPa– Tinit = 90 °C– tpressurize = 130 s– thold = 220 s– tdecompression = 15 s

packs

vessel

air

End of holding time; t = 350 s

Knoerzer et al. 2007; Juliano et al. 2009


Multiphysics CFD as a design tool

CFD

…

log(

N/N

0)

Modelling can be used for:

Model

Tem

pera

ture

di

strib

utio

nIn

activ

atio

n di

strib

utio

n

Scenario 1 Scenario N


Challenges and recommendations


Key success indicators• High Pressure Processing presents potential benefits for low acid food

sterilization• Synergistic inactivation effectiveness• Increased shelf life• Economical benefits

• Control of the preheating step is essential• Retention of heat in the chamber must be maximized to increase inactivation

efficiency • The technology has proven to work for vegetables, meat, and egg products • Product formulation optimization is necessary to come up with the most

adequate novel products• Microbial challenge studies and proper modeling of inactivation kinetics is

fundamental for process validation• The right packaging materials must be identified• NUTRIENT RETENTION IS KEY FOR PRODUCT DIFFERENTIATION FROM

CANNED/THERMALLY TREATED PRODUCTS


Commercialisation prospects• Industry must weight quality benefit vs. costs• The HPT process must sell convenience, quality and nutrition

(healthy options)• Consumer acceptance is imperative • Optimal treatment conditions must be identified for each

products• Safety must be assured through validation and work with

regulatory agencies• Process Capability to be determined

•Must optimize formulation and processing steps•Go beyond “squeeze and taste”•Reliability and repeatability•Regulatory boundaries – easier first: CFR 113•Meet shelf life goals with proper packaging•HACCP / GMP

Barbosa-Canovas and Juliano, 2006


CSIRO HPP/HPT team

• Dr. Mary Ann Augustin• Dr. Roman Buckow• Dr. Michelle Bull• Dr Janelle Brown• Dr. Mala Gamage• Dr. Pablo Juliano• Mr. Michael Kelly• Dr. Geoff Knight• Dr. Kai Knoerzer• Mr. Andrew Lawrence

• Ms. Sieh Ng• Ms. Sandra Olivier• Ms. Anita Sikes• Mr. Lloyd Simons• Mr. Rod Smith• Dr. Robert Steel• Mr. Daryl Unthank• Dr. Sandani Udabage• Dr. Kees Versteeg• Dr. Robyn Warner• Others


Thank youDr Pablo JulianoSenior Research Scientistt +61 3 9731 3276e [email protected] www.csiro.au/fns

CSIRO ANIMAL, FOOD AND HEALTH SCIENCES

high pressure thermal processing of foods - innova · outline • high pressure thermal processing...

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