Nicht-thermische Verfahren zur Entkeimung und Strukturbeeinflussung von Lebensmitteln Volker Heinz Stefan Töpfl

Struktur – Prozess - Funktion

Vielfältiger Hochdruck

Druck – Zeit - Bereiche 1400 1200

Pressure [MPa]

1000 HPST

800 600

Shock wave

Industrial HPP

400 Ultrasound

200 0 1,00E-07

1,00E-05

Gun

1,00E-03 1,00E-01 Time [s]

1,00E+01

1,00E+03

Stosswellen

Application of 50 – 100 g explosives (Hydrodyne®)

Long. 1997, Solomon 2002

http://www.las.ele.cst.nihon‐ u.ac.jp/History/kidn.html

http://www.mwstone.com/howthe.htm

Anwendungen von Stosswellen

Wess

6

Anwendungen von Stosswellen Gesteinssprengen Discharge

Electrodes

Water Bassing

Shockwave

Impact Material

Löffler, 2007

7

Anwendungen von Stosswellen • TenderClassTM-System [Hydrodyne Inc., University of Wisconsin] Claus

Claus

8

Anwendungen von Stosswellen Fleischreifung

CONTROL: Magnification 7100X. Early deboned Holstein beef before TCS processing. Intact myofibrils.

Hydrodyne Processed: Magnification 19500X. Early deboned Holstein beef after TCS processing.

Claus et al. 2002

Anwendungen von Stosswellen Fleischreifung

Moeller et al. 1999

Shock Generation

Gepulste elektrische Felder

Cell Membrane D= 40-200 µm

D= 30-100 µm

D=

10 1

µm

5 nm

Cellular Systems Exposed to Electric Fields ∼ V(ω)

∼ V(ω) Frequency

Frequency:

MHz

Hz

σ (ω) =

k Z ( jω)

σ [mS/cm]

Conductance versus Frequenz (β-Dispersion: 3kHz - 50 MHz)

Z(jω)- Impedence, Ω

10

3

10

4

5

6

10 10 10 Frequenz [Hz] Frequency [Hz]

7

10

8

Electrophysical Model of Cellular Materials Permeabilized Cell

l

b Unhomogenity

H Measurement Current Flow

d

Conductance σ

Total Rupture

behandeltes Zellsystem

Intact Tissue

a

L Basiselement: intakte Zelle

3

10

4

5

6

7

10 10 10 10 Frequenz [Hz] Frequency [Hz]

Electrophysical Model of Cellular Materials Intact Membrane

Permeabilized Membrane Cm

Cm Cp

Rm →∞ ε = 2.3 Cm = 1 µF/cm²

Plant Cell Model: R6 C1 C2 Rm1

R4

R3

Rm2

R5

Rm

Rm Rp

Electrophysical Model of Cellular Materials intact Membrane

permeabilized Membrane Cm

Cm Cp

Rm →∞ ε = 2.3 Cm = 1 µF/cm²

Plant Cell Model: R6

C2

R4

Rm Rp

Permeabilization Index

σ hi t i ⋅ σ − σ l l σ ht ZP= σ hi −σ li

C1

Rm1

Rm

R3

Rm2

R5

Zp= 0 → intact Tissue; Zp= 1 → max. Dieintegration

Application of Pulsed Electric Fields Gentle Juice Preservation

Inactivation of different microorganisms 0

lg (N/N0)[-]

0

0

0

-1

-1

-1

-1

-2

-2

-2

-2

-3

-3

-3

-3

-4

-4

-4

-4

-5

-5

-5

-5

-6

-6

-6

-6

-7

E. coli 0

40

-7 80

120

L. innocua 0

40

80

-7 120

S. cerevisae 0

40

80

-7 120

35°C 45°C 55°C

B. megaterium 0

40

80

120

-1

Specific Energy [kJ kg ]

Inactivation of E. coli, L.innocua, S. cerevisae and B. megaterium in ringer solution with an electrical conductivity of 1.25 mS cm-1 after PEF treatment with graphite anode and a field strength of 16 kV cm-1

E. sakazakii 0 -1 -2

-2

log (N/No)

40°C

-3 50°C

-4 55°C

-5 -6

Infant formula 30 kV/cm rectangular 10 µs width

-3 -4 -5 -6

-7

-7 0

50

100

150

200

25

35

spec. energy input (kJ/kg)

55

65

75

85

30°C

40°C

50°C

0

-1

-1 30°C

-2

log (N/No)

-2

log (N/No)

45

temperature after PEF (°C)

L. monocytogenes

0

Protective effect in comparison to Ringer solution (dotted lines)

40°C 50°C 55°C

-1

30°C

log (N/No)

3.5 log-cycle inactivation below 72 to 75°C

30°C 0

-3 -4 -5 40°C

50°C

-6

-3 -4 -5 -6 -7

-7 0

50

100

150

spec. energy input (kJ/kg)

200

25

35

45

55

65

75

temperature after PEF (°C)

85

0 -1

log (N/No)

Integration of temperature-time-profile Evaluation of thermal and PEF effects Determination of c-value

Temperature (°C)

40°C

-3 50°C

-4 55°C

-5 -6

3.5 log-cycle of E. sakazakii 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20

30°C -2

-7 0

50

100

150

200

spec. energy input (kJ/kg)

PEF, 100 kJ/kg PEF, 60 kJ/kg

Thermal inactivation tx

∫ − k(T(t))dt N (t ) = e 0 N0

cooling

k = e a ⋅T - b

preheating

Product deterioration t

0

10

20 Time (s)

30

c - value = ∫ 10 0

T − Tref z

dt

30°C

0

E. sakazakii

-1

-1

30°C -3

log (N/No)

log (N/No)

-2

40°C 50°C

-4 55°C

-5 -6

-3 -4 -5 -6

-7

-7 0

50

100

150

200

25

spec. energy input (kJ/kg) 30°C

-1

55

65

75

85

40°C

Thermal inactivation

50°C

15s

-1

30°C

-2

-3

log (N/No)

log (N/No)

45

0

-2

Protective effect in comparison to Ringer solution (dotted lines)

35

temperature after PEF (°C)

0

L. monocytogenes

40°C 50°C 55°C

0

-2

Comparison to thermal portion of inactivation

Thermal inactivation

-4 -5

-4 -5

40°C

50°C

-6

-3

-6

-7

-7 0

50

100

150

spec. energy input (kJ/kg)

200

25

35

45

55

65

75

temperature after PEF (°C)

85

Project Example

Inactivation of Enterobacter sakazakii in heat sensitive emulsion Tmax 72°C

30°C

40°C 50°C 55°C

0 -1

log (N/No)

-2 -3 -4 -5 -6 -7 25

35

45

55

65

75

85

temperature after PEF (°C) Pilot scale test, 200 l/h

PEF enhanced drying of Meat PEF treatment (1 – 5 kV/cm)

Brine Injection (10 %) 10 % of brine, saturated

Hand salting (5 %) 5 % of salt on surface

Drying at 8 °C, 95 % rel. humidity

PEF enhanced drying of Meat Drying curve of pork meat 112.0

relative weight (%)

110.0

108.9 106.7 106.1

100.0

99.5

90.0

88.8 87.5

86.2

82.8

81.8

80.0

78.2 72.6 70.2

70.0

3KV/cm (exterior); 100 p control 3KV/cm (injection); 200 p control injection

60.0

64.4 61.6 57.7

50.0

0

50

100

150

200

drying time

250

300

350

Equipment development

Concept for treatment of meat pieces

product transport

Cost impact of specific energy input Specific energy (kJ/kg)

Total treatment costs (ct/l)

Capacity (l/h)

100 l/h

0,100

100 10000

Average Power

1 t/h

309

Operation per day (h)

14

Annual production (l)

30800000

Cost parameters Investment (EUR)

0,010

848765

Depreciation range (a)

10 t/h

5

Maintenance (EUR/h)

Disintegration

Preservation

1,69

Electrical power (kWh)

950617

Elelcrical Power (EUR/kWh)

55°C 50°C

0,001

100

1000

specific energy input (kJ/kg)

7000

169753

Electrical Power (EUR)

85556

Personnel

46200

Total (EUR)

306737

0

6000

Costs per l of product

-1 30°C -2

5000

log (N/No)

Power supply costs (Eur/kW)

10

Depreciation (EUR)

20°C

0,09

4000

40°C

-3 50°C

-4

-7

Degression of investment cost 2000

0

50

100

150

200

0,55

Electricity

0,28

Personnel

0,15

Maintenance (ct/l)

0,15

Total (ct/l)

1,13

55°C

-5 -6

3000

Depreciation

0

50

100

150

spec. energy input (kJ/kg)

200

Average power (kW)

without cooling efforts

5 kW technical scale system

30 kW industrial scale system

Hydrostatischer Hochdruck

microbes starch tissue lipids proteins

Inactivation

Swelling

Disintegration

Transition

Unfolding

Industrial HPP machines in the world (number of equipment)

112 99 83

O cea n i a Asi a Eu r op a Am er i ca Tota l

68

65

53 41 31 23 22

19 10 9

9 1

1

2

3

2

06

05

l ta To 7 0

20

20

03

02

01

00

99

98

97

96

95

94

93

92

90

91

19

19

19

19

19

19

19

19

19

19

20

20

1 1

04

1

2 4

20

1

1

3

2

20

1

1

3

20

1

1

2

6 3

3

8

9

6

7

20

2

12 4

1

1

1

1

5

3

2

1

7

8

7

7

10

Industrial HPP machines versus food industries (% total number of machines)

Vegeta ble products 33%

9

112 HPP machines

9

60 companies

9

Production in 2006 :

Mea t products 28%

> 120 000 tons Sea food a nd fish 15% Juices a nd bevera ges 17%

Others products 7%

Color changes of meat during HPP

Pressure-temperature diagram ΔE color change of chicken, turkey and pork meat after 1 min treatment time.

Color changes of meat during HPP

pT diagram for 5 log inactivation of Y. enterocolitica, Campylobacter spp and Avian Influenca Virus in pork and poultry meat.

SEM Chicken

Reference

400 MPa / 15° C / 1 min

300 MPa / 15° C / 1 min

500 MPa / 15° C / 1 min

Ezymatische Reaktion unter Hochdruck starch native

E+S

inactivation

ES

E+P

Activity under pressure pT dependence of the corrected conversion rate constant kconv of glucoamylase (A.niger).

pT isokinetic diagram for 95% inactivation amylases and cellulases ACES buffer after 30 minutes exposure time.

starch native E+S

ES

inactivation

E+P

starch swelling Loss in birefrigence

Buckow et al., 2007

mechanisms

Saccharification of native maize starch by glucoamylase in different p/T domains starch native E+S

ES

E+P

inactivation d [Glucose ] = k conv ⋅ [E1 + E 2] ⋅ [S ] dt d [E1 + E 2] = −k1inact ⋅ [E1] − k 2inact ⋅ [E 2] dt d [S ] −1.65 = 1 − (k gel ⋅ [S ] ) dt

Liberated glucose from maize starch by glucoamylase versus temperature and pressure after 30 minutes. Isolines denote the percentage relative to the maximum release observed at 270 MPa and 80°C.

Überkritisches Wasser

Supercritical water

Applications

Supercritical Water Oxidation Pectin Hydrolysis for production of Oligo-galacturonicacids Sludge disintegration Decontamination of hazardous wastes

Technical scale prototype, 300 bar, 500 °C, Residence time 1 – 120 s

Pectin de-polymerization DP1

DP2

DP3

DP4

DP5

DP6

DP7

DP8

DP9

DP2 En

DP3 En

DP4 En

DP5 En

DP6 En

DP7 En

240°C/ 200bar

230°C/ 200bar

220°C/ 200bar

210°C/ 200bar

200°C/ 200bar

0%

10%

20%

Contact time: 5s

30%

40%

50%

60%

70%

80%

90%

100%

Pectin de-polymerization DP1

DP2

DP3

DP4

DP5

DP6

DP7

DP8

DP9

DP2 En

DP3 En

DP4 En

DP5 En

DP6 En

DP7 En

200°C/ 200bar

200°C/ 170bar

200°C/ 130bar

0%

10%

20%

Contact time: 5s

30%

40%

50%

60%

70%

80%

90%

100%

Interesting Area

280 260 supercritical

240

Nonhydrolysed pectin

220 200

221bar subcritical

Pressure (bar)

180

374°C critical point

160 140 120 liquid

100 80

Total hydrolysis gas

60 40 20 0 0

100

200 300 Temperature (°C)

400

500

Hydrostatischer Hochdruck

Wave 600 0/1 35

MODELL

Arbeitsschritte

Wave 600 0/4 20

Maßeinheit

Behälterauslastung

Abschätzung der Gesamtkosten

Wave 600 0/3 00

50%

60%

80%

Maschinenbeschickung in *

Minuten

1,4

1,4

1,7

Druckaufbau in

Minuten

4,2

3,3

3,3

Druckhaltezeit in

Minuten

3

Gesamtbearbeitungszeit in

Minuten

Druckbehälter Volumen in

Liter

3

3

8,6

7,7

8

135

300

420

23

23

23

Laufzeit Tagesbetriebseinsatz in

Stunden

Arbeitstage pro Jahr

Tage

250

250

250

998

1596

1950

Anschaffungskosten und Verbrauchsdaten Investitionsvolumen**

i. Tausend €

Abschreibungsdauer

Jahr

5

5

Energiebedarf

kWh

36

88

5 119

Betriebsleistung Stundenleistung in

Kilogramm

Jahresproduktion in

Tonnen

471

1403

2520

2708

8065

14490

Behandlungskosten pro Liter oder Kilogramm Abschreibung in

€

0,074

0,040

0,027

Verschleißteile in

€

0,050

0,028

0,018

Energiekosten in

€

0,003

0,003

0,002

Gesamtkosten in

€

0 127

0 070

0 047

Total cost estimation for • High Pressure Low Temperature 600 MPa, 5 min, Tini = 5°C Vessel = 325 L • High Pressure Thermal Sterilisation 600 MPa, 5 min, Tini = 90°C Vessel = 125 L (Buckow et al. 2008)

Sensitivity Analysis

(Buckow et al. 2008)

Zusammenfassung: Prozessentwicklung

Zusammenfassung: Mechanismen