iaal d. bounie, e. van hecke : high moisture extrusion - sydney, dec. 2 nd 97 high moisture...

iaal D. Bounie, E. Van Hecke : High moisture extrusion - Sydney, dec. 2nd 97

High moisture extrusion : optimisation of texturisation

through control of rheologicaland textural parameters

D. Bounie, E. Van HeckeUSTL (Université des Sciences et Technologies de Lille)

IAAL (Institut Agricole et Alimentaire)Bâtiment C6

59655 Villeneuve d’Ascq Cedex - FranceTel : +33 (0)3 20.43.49.21, Fax : +33 (0)3 20.43.44.86E-Mail : [email protected], [email protected]

Smart Extrusion Workshop, Sydney,2 december 1997

(p1)


PLAN

(p2)

High moisture extrusion

Usual extrusion conditions (50 - 80 % water, 15 - 30 % proteins, fats <8 %,

> 130 °C) and consequences (reduction of : shear, viscous dissipation of

energy and expansion at die outlet, especially with long cooling dies)

Raw materials Main applications Typical extrusion line

• specific feeding device• special screw profiles (+ break plates)• long cooling-dies• temperature control

Fundamentals of high moisture texturization during extrusion-cooking

Main steps • protein melting (plasticising) : within the extruder• material texturization (fibration) : along the die

Flow in extruder and die during texturization Control of texturization through control of rheological behaviour

• (shear) viscosity• elasticity• visoelasticity• elongational viscosity

Correlation between on-line and off-line assessment of rheological and

textural parameters

Perspectives













textural parameters

Perspectives

PLAN


Wet extrusionvs. dry extrusion

(Roussel, 1996)

HIGH MOISTURE EXTRUSION : APPLICATIONS

(p3a)

0 %

20 %

40 %

60 %

80 %

Moisturecontent %

Confectionery

Dry petfoods

TVPPetfood-moist

Pasta

Snacks - Flat breads

Breakfast cereals

Cheese analogs Enzyme reactors

Fruits and vegetables

Wet extrusion : usual raw materials(Roussel, 1996)

Animal raw materials red and white meat minces meat trimmings fish meats (surimi) filleting co-products minced from shell fish or cephalopoda egg or milk proteins

Vegetable raw materials protein-rich meals protein concentrates or isolates (soya, wheat, peas, brans,...) after adequate rehydratation

APPLICATIONS (Cheftel and al., 1992)

Sterilization preparation of sterile vegetables purées, meat-vegetables mixes

Chemical reaction (enzymic or acid hydrolysis) starch or proteins modification for preparation of glucose syrups,

fermentation substrates, flavor preparationsTexturization Gelation/fibration

gelation and fiber formation using vegetable proteins (soya, gluten) restructuration of mince, surimi, mechnically deboned meats (with

binders) texturization and fiber formation with fish muscle proteins

Emulsification/gelation : « microcoagulation » of dairy proteins processed cheeses cheese analogs fat substitutes casein coagulation

iaal D. Bounie, E. Van Hecke : High moisture extrusion - Sydney, dec. 2nd 97 (p3b)

MACRO AND MICRO STRUCTURES OF FIBROUS EXTRUDED PRODUCTS

A commercial extruded crab analogfrom Nippon Suisan(Cheftel and al, 1992)

Scanning electron micrographsof an extruded

surimi/soya concentrate mix(Thiebaud,1995)


TYPICAL EXTRUSION LINEFOR PRODUCT FIBRATION

(p3c)

Feeding device

Twin screw extruder with accurate temperature control

Gear pump

Extra long cooling die (Nippon Suisan patent)













textural parameters

Perspectives

PLAN


TEXTURIZATION : MELTING + FIBRATION

(p4)

Flow in extruder and cooled die

Metering zone Transition zone Die

Structure formation as a result of phase separation in biopolymer mixtures followed by subsequent orientation in flow

through die(Tolstoguzov, 1986 ; Mitchell et al., 1994)

Biopolymer phases separate into different domains

in extruder

Domains orientate as a result of flow through die

Products sets to fibrous structure on cooling













textural parameters

Perspectives

PLAN


COOLING DIES FOR TEXTURATION

Rectangular die

(p5)

Circular die

Annular die


FLOW PATTERN IN EXTRUDER AND DIE(Bhattacharya and Padmanabhan, 1992)

(p6)

Metering zone Entranceregion

Viscometric flowregion

Exitregion

Intermediaryregion

(relaxation)

P

die axis

Shear flow

Pentry

Extensional flow Shear flow

Pexit

Pshear flow

Ptotal = Pentry + pshear flow + Pexit


FLOW PROFILES THROUGH DIESEffect of cooling

(p7)

Flow through insulated die

Flow through supercooled die

Liquid Liquid / solid Solid


EFFECT OF OPERATING CONDITIONS ON FLOW,TROUBLESHOOTING

(p8)

Effect of implementing a non-newtonian fluid

m = 1m < 1

m << 1

Effect of viscosity

Increase of viscosity

Decrease of viscosity :

. increase of water content. increase of temperature

Troubleshooting

«Shark-skin» : periodic rupture of fluid bed (no slip at die wall)

«Two-phases wavy flow» : insufficient cooling rate (die too short or too thick) ; inner layers of flow are still melted at die outlet













textural parameters

Perspectives

PLAN


STRESS TENSOR

(p9)

2,1

1,3

3,2

3,1

1,22,3

2

3

1

Shear stress (if no rotation, i.e. no torque)

3,1 = 1,3

3,2 = 2,3 2,1 = 1,2

N1 = 1,1 - 2,2 (first normal stress difference) = e = k ( : elongational strain rate)

N2 = 2,2 - 3,3 (second normal stress difference)

N2 < 0, N2 << N1

2 .

Normal stress

1,1

2,2

3,3

2,2

3,3

1,1


SHEAR VISCOSITYT

(p10)

F

S

dl

x

dxv

v = dl

dtshear velocity (m.s-1)

T = F

Sshear stress (N.m-2 = Pa)

= dv

dxshear rate (s-1).

Ts = shear viscosity (Pa.s)

.

.

T

s

Bingham plastic

Newtonian

Pseudoplastic(shear thinning)

Dilatent(shear thickening)

T,o

Yieldstress


VISCOSITY : LAWS OF BEHAVIOUR

(p11)

constantNewtonian

Power law (Ostwald’s law)(K : index of consistency,m :flow behaviour index

m-1.Non Newtonian

m-1) e -T.

Effect oftemperature T

(Harper and al., 1971)

m-1 ) e -MC.

Effect ofmoisture content MC(Harper and al., 1971)

m-1)e dt - k e

-ERTa(t)

.

Effect of chemical reaction (E, R)(Remsen and Clark, 1978)

m-1 ) e -W.

Effect of thermo-mechanical history W (SME)

(Della Valle and Vergnes, 1994)

= Ko e ( - a MC - b W)

m’-1

with : m’ = c1 T + c2 MC + c3 MC.T

.ERTa

Example : corn starch at low MC(Della Valle and Vergnes, 1994)


IN-LINE MEASUREMENT OF VISCOSITY

(p12)

Qv

P

L

L

P

(Mac Master and al., 1987)

Shear stress at wallw

Apparentshear rate at wall

w, a

.

Realshear rate at wall

w, r

.Viscosity

RR P 2 L

4 Qv

R3

4 Qv

R3

3m + 1

4m

w

w, r

.

h P 1 2 L 1 +

hW

6 Qv

W h2

6 Qv

W h2

2m + 1

3mh

Ww

w, r

.

Log K

Log w

Log w, a

.

for different Qv

m


IN-LINE RHEOMETERSWITH CONTROLLED FEEDRATE

(p13)

By pass or side stream rheometers (Goettfoert system for plastics)

Gear pump

Rheometer

Derivation

« Rheopac » slit die rheometer (Vergnes et al., 1990 and 1993)

Piston keys


DISPLAY OF ELASTICITY :Weissenberg effect, Barus effect

(p14)

Weissenberg effect

increase with increasing

.

N

T

die extrudate

Barus effect : swelling at die outlet

T

N)N


IN-LINE MEASUREMENT OF ELASTICITY :EXIT PRESSURE METHOD(Padmanabhan and Bhattacharya, 1991)

(p15)

P

L

Pentrance

related to extensional viscosity

Pexit

proportional to elasticity


Qv

IN-LINE MEASUREMENT OF ELASTICITYHOLE PRESSURE METHOD

( Baird, 1976 ; Padmanabhan and Bhattacharya, 1992 ; Bhattacharya M. and Padmanabhan M., 1992, Malkus and al., 1992 ; Bouvier and Gelus,

1994)N

(p16)

P1 P2 P3

flush-mounted transducers

P

P1

P2

P3

P1,3 (shear viscosity)

L

P4

transducer at the bottom of the hole

P4

phole (elasticity)

N1 = 1,1 - 2,2 = e


DYNAMIC DETERMINATIONOF VISCOELASTICITY (1)

(Ross-Murphy, 1988)

(p17)

Force transducerAccelerometer

Imposed oscillatory

strain = f(t)

Measured stress = f(t)

Viscous fluid

Strain

(t)cost

t

Stress

(t)cost

2

Elastic fluid

Stress

Strain

t

Viscoelastic fluid

Stress

t

2

Strain


DYNAMIC DETERMINATIONOF VISCOELASTICITY (2)

(p18)

log scale

Viscosity

Ideal viscous liquid

Newton’s law

Loss modulus

.

G’’ = sin 0

0

Temperature

G’’

Elasticity

Ideal elastic solid

Hooke’s law

Storage modulus

G’ = cos 0

0

G’

Viscoelasticity

Viscoelastic fluid

G’’G’ = tg

Transition

or tg


ELONGATIONAL VISCOSITY

s

e

Newtonianfluid

Non-newtonianfluid

(Troutonmodulus)

Type of extensional flow

(p19)

Uniaxial extension

ex : spinning of fibers

3 >> 3

Planar extension

ex : foil stretching, central disk injection

4 >> 4

Biaxial extension

ex : blowing extrusion, plug extrusion

6 >> 6


ELONGATIONAL vs. SHEAR VISCOSITY

(p20)

Newtonianfluid

s

.

Non-newtonianfluid

s

.

e

e

s

e

constante

[= f(.s

e

= constante

In-line determination of extensional viscosity :Entrance pressure drop method(White and al., 1987 ; Bhattacharya and al., 1994)


PLAN












textural parameters

Perspectives


PERSPECTIVES : NEW DIES ?

(p21)

Breaker plates


• Baird D.G., 1976. Fluid elasticity measurements from hole pressure error data. J. Appl. Polym. Sci, 20, pp 3155-3173.• Bhattacharya M. and Padmanabhan M., 1992. Extrusion processing : texture and rheology. In : Encyclopedia of Food and Science Technology, Hui Y.H. Ed., Willey Interscience, New York, pp 800-814.• Bhattacharya M., Padmanabhan M. and Seethamraju K., 1994. Uniaxial extensional viscosity during extrusion cooking from entrance pressure drop method. J. Food Sci., 59(1), pp 221-226, 230• Bouvier J.M. and Gelus M., 1994. Apport des mesures en ligne à l’analyse du procédé de cuisson-extrusion. In : La Cuisson-Extrusion, Colonna P. and Della Valle G. Eds., Tec & Doc Lavoisier, Paris, pp 323-355.• Cheftel J.C., Kitagawa M. and Quéguiner C., 1992. New protein texturization processes by extrusion cooking at high moisture levels. Food Rev. Int., 8(2), pp 235-275.• Cheftel J.C., Kitagawa M. and Quéguiner C., 1994. Nouveaux procédés de texturation protéique par cuisson-extrusion à teneur élevée en eau. In : La Cuisson-Extrusion, Colonna P. and Della Valle G. Eds., Tec & Doc Lavoisier, Paris, pp 45-84.• Cheftel J.C. and Dumay E., 1993. Microcoagulation of proteins for development of "creaminess". Food Rev. Int., 9(4), pp 473-502.• Della Valle G. and Vergnes B., 1994. Propriétés thermophysiques et rhéologiques des substrats utilisés en cuisson-extrusion. In : La Cuisson-Extrusion, Colonna P. and Della Valle G. Eds., Tec & Doc Lavoisier, Paris, pp 439-467. • Harper J.M., Rhodes T.P. and Wanninger L.A., 1971. Viscosity model for cooked cereal doughs. A.I.Ch.E. Symposium Series, 676(108), pp 40-43.• Malkus D.S., Pritchard W.G. and Yao M., 1992. The hole-pressure effect and viscosimetry. Rheol. Acta, 31, pp 521-534.• Mc Master T.J., Senouci A. and Smith A.C., 1987. Measurements of rheological and ultrasonic properties of food and synthetic polymer melts. Rheol. Acta, 26, pp 308-315.• Mitchell J.R., Areas J.A.G. and Rasul S., 1994. Modifications chimiques et texturation des protéines à faible teneur en eau.. In : La Cuisson-Extrusion, Colonna P. and Della Valle G. Eds., Tec & Doc Lavoisier, Paris, pp 85-104.• Padmanabhan M. and Bhattacharya M., 1991. Flow behavior and exit pressures of corn meal under high-shear-high-temperature extrusion conditions using a slit die. J. Rheol., 35(3), pp 315-343.• Padmanabhan M. and Bhattacharya M., 1992. Rheological measurement of fluid elasticity during extrusion-cooking. Trends in Food Science and Technology, 6, 149-151.• Quéguiner C., Dumay E., Cavalier-Salou and Cheftel J.C., 1991. Application of extrusion cooking to dairy products : preparation of fat analogues by microcoagulation of whey proteins. In : Applied Food Extrusion Science, Kokini J. and al. Eds., Dekker, New York, pp 363-376.• Quéguiner C., Dumay E., Cavalier-Salou and Cheftel J.C., 1992. Microcoagulation of a whey protein isolate by extrusion cooking at acid pH. J. Food Sci., 57, pp 610-616.• Remsen C.H. and Clark J.P., 1978. A viscosity model for a cooking dough. J. Food Process Eng., 2, pp 39-64.• Ross-Murphy S.B., 1988. Small deformation measurements. In : Food Structure : its Creation and Evaluation, Blanshard J.M. and Mitchell Eds., Butterworth, London, pp 387-400.• Roussel L., 1996. Making meat products using extrusion technology. Extrusion Communiqué, nov-dec, pp 16-18.• Thiebaud M., 1995. Texturation par cuisson-extrusion de mélanges protéiques hydratés à base de surimi de poisson. Influence des paramètres opératoires et de la formulation sur les caractéristiques biochimiques et physicochimiques des extrudats. PhD. Thesis, University of Montpellier.• Tolstoguzov V.B., 1986. Functional properties of protein-polysaccharides mixtures. In : Functional Properties of Food Macromolecules, Mitchell J.R. and Ledward D.A. Eds., Elesevier Applied Science Pub., London, pp 385-415.• Vergnes B., Della Valle G. and Tayeb J., 1990. Rheopac : a new on-line rheometer with controlled feed rate to determine the viscosity of starchy products. In : Proceedings of ACoFoP2, 13-14 nov. 1990, Bimbenet J.J. and Trystram G. Eds., Paris.• Vergnes B., Della Valle G. and Tayeb J., 1993. Rheopac : a specificin-line rheometer for extruded starchy products. Design, validation and application to maize starch. Rheol. Acta, 32, pp 465-476.• White S.A, Gotsis A.D. and Baird D.G., 1987. Review of the entry flow problem : experimental and numerical. J. Non-Newtonian Fluid Mech., 24, pp 121-160.

BIBLIOGRAPHY

(p22)

iaal d. bounie, e. van hecke : high moisture extrusion - sydney, dec. 2 nd 97 high moisture...

Documents

control of texturization

dry extrusion roussel

vegetables wet extrusion

smart extrusion workshop

moisture content

main applications

long cooling dies

die outlet