What is F-D?
Force
object
Deformation
What properties can be
studied?
Hardness
The force necessary to attain a given deformation
Cohesiveness
The strength of the internal bonds making up the
body of the product
Viscosity
The rate of flow per unit time
Springiness
The rate at which a deformed material returns to its
original condition after deforming force is removed
Adhesiveness
The work necessary to overcome the attractive
forces between the surface of the food and the
surface of other materials (tongue, teeth etc.)
Fracturability
The force at which material fractures
Gumminess
The energy required to disintegrate a semisolid food
product to a state ready for swallowing
Chewiness
The energy required to masticate a solid food
product to a state ready for swallowing.
Examples- pasting
properties of cooked rice
• Back Extrusion test (BE)
5
F
F orc e (kg)
4
3
2
1
0
0
40
80
120
Time (s)
160
200
How to measure visco-elastic
nature of foods?
• Instron texture
analyzer
Different Tools
Shear Extrude Compression
Fruits Vegetables
Cooked Pasta Cubed Chicken
Viscous Liquids
Gels
Puncture
Fruits Vegetables Nuts
Deformation TPA
Bread Candy Cheese
Gels Rolls
Compression Shear
Extrusion
Fruits Vegetables
Ground Meat Seafood Salad
Viscous Liquids Gels
Shear Extrusion
Fruits Vegetables
Viscous Liquids Gels
Tension
Raw Pasta
Processed Meat
Bend Snap
Crackers Cookies
Granola Bars Raw
Pasta
How to measure?
hardness
energy
adhesion
stickiness
Single Kernel Hardness
Measurement
Example for various tests
• Bakery
• Fruit & Vegetables
• Pasta, Noodles & Rice
• Pet Food
• Snack foods
Bakery
Viscosity
25mm. Ball Probes
#Compress to limit and pull
• Result = Positive (i.e.
'Hardness')
• Result =negative (i.e.
‘Viscosity') Peak force values
Hardness
Viscoscity
Bakery
Margarine B
• Magarine
• Forward extrusion with 3mm
extrusion disc
• Containers are half filled with
the margarine samples
• Results = Average Force
• Result = force plateau ('ease of
extrusion')
Margarine A
Bakery
• BISCUIT
• 6 mm. cylinder probe Compress
to limit
• Results = maximum peak force
("Hardness")
cylinder probe
Sample
Plunger
Bakery/BREAD
• BREAD
• 36mm cylinder probe Compress
to 40% strain
• Results =compression force
('Firmness') at 25% compression
36mm cylinder probe
Bread / Firmness
Bakery/Cake
• 36mm cylinder probe Compress to % strain and hold time 60 s.
• Results = compression force (Firmness and Springiness) values at 25%
compression:
Fruit & Vegetables
• Rice and Bean
• Ottawa Cell Compression to
limit and then weighed into
200g
• Results = maximum peak force
(Firmness) values, and Work of
Extrusion values
GRAPES
• 2mm cylinder probe
Compress to limit
Being tested with a texture
probe to determine the skin
strength.
Noodles
• NOODLES
• Spaghetti tensile grips
• Dry noodles were placed in boiling water for 10 minutes and rinsed
with cold water
• After rinsing the samples and left to dry slightly for 15 minutes.
• Results = Peak force values and Elongation
Noodles
Spaghetti tensile grips
Rice
•
•
•
•
•
Hardness and Stickiness of four varieties of cooked rice
35mm cylinder probe compressed to 90% of their size the probe
200g of rice was weighed into a container
Results = +Peak Force values ('Hardness')
Results = - Peak Force ('Stickiness')
Rice
Hardness
35mm cylinder probe
Stickiness
Firmness of grain or cereal
Pet Food
• Hardness of Pellets by
compression
• 35mm cylinder probe Compress
to limit
• Results = Maximum peak force
values ("Hardness")
35mm cylinder probe
Wet Cat food
• Ottawa Cell with Wide Blade
Extrusion Plate
• Compress to limit
• Results = maximum peak force
("Firmness")
• Results = area under the curve
("Work of Extrusion")
Wide Blade
Ottawa Texture Cell
Fruits Vegetables Viscous Liquids Gels
Test Mode Shear Extrusion
Dog biscuit bending
• 3 Point Bend Fixture
• Compression to limit
• Result = Peak Force
(“Hardness”)
Snack Foods
• TORTILLA-TYPE SNACK
FOOD
• 1/4" Ball Probe and Support
Ring ,Compress to limit
• Results = Peak force
1/4" Ball Probe
Support Ring
Wafer to Fracture
• 3-Point Bending Rig
• Compress to limit
• Results = Peak force value, the
distance compressed before
breaking
Spreadability
•
•
•
•
45 degree cone probe
Compress to limit
Result = Peak force
Result = Work of shear
Toothpaste Firmness
'Force to Extrude'
Hemispherical blade
adjustable support length
Compress to limit
Result = Maximum extrusion force and work of extrusion' values
Bending Force of lipsticks
•
•
•
•
•
•
Lipstick Cantilever Rig
Hemispherical blade
Compress to Rupture
Results = Maximum force
Results = Distance at break
Results = Modulus
10 0C
25 0C
Full-Fat and Low-Fat
Yoghurt by Back extrusion
• YOGHURT
• Back Extrusion Cell
• Original yoghurt (150g) immediately after removal from storage at
5.0°C.
• Compress to limit
• Results = Peak force values and Area under the generated force
YOGHURT
Back Extrusion Cell
ADHESIVE GUM
• 4mm cylinder probe
• Compress to limit (Distance2 mm)
• Wide strips of adhesive (of
approximately 4mm thickness)
• Result = Positive (i.e. 'Hardness')
• Result =negative (i.e. 'Stickiness')
peak force values
GUM
ADHESIVE GUM
4mm cylinder probe
Hardness
Stickiness
Warner-Bratzler Shear
Food after different cooking times using Knife Blade
• Knife Blade
• Then cooked separately for the following times
a) 0 mins, i.e. raw
b) 1 min
c) 2 mins
d) 3 mins
• Compress to limit
• Results = Peak force
Warner-Bratzler Shear
a) 0 mins
b) 1 min
c) 2 mins
d) 3 mins
Warner-Bratzler Shear
CHOCOLATE COATED WAFER BISCUITS
• Knife Blade
• Compress to limit
• Results = The first peak force readings ( cutting of the
first wafer layer) (“Hardness”)
Graph
CHOCOLATE COATED WAFER BISCUITS
First Wafer layer
Graph
Hardness measurement of Biscuits by cutting
Hardness
Compression Strength of Fresh Eggs
Compression to limit
Results = Peak Load
Kramer Shear cell
• Fruits Vegetables Cooked Pasta Cubed Chicken Viscous Liquids Gels
• Test Mode Shear Extrude Compression
Compression Plate
Bread Candy Cheese Gels Rolls
Test Mode Deformation TPA
Texture Profile Analysis
1, Initial step is begun at the first bite
2, Masticatory step is perceived during chewing
3, Residual step is perceived after the mastication and
swallowing
Textural Properties of Foods
• Textural properties of food are those
characteristics that are sensed by the feeling of
touch, and are related to deformation,
disintegration, and flow of food under the
application of forces.
• These properties can be measured objectively as
function of force, distance, and time.
• Textural properties of foods are greatly influenced
by internal structure and other variables such as
size, shape, moisture, and fat contents and their
inter-relationships.
Textural Characteristics
• Hardness: the force (kg) necessary to attain a
given deformation.
• Cohesiveness: the strength of the internal bonds
making up the body of the product (A1/A2).
• Elasticity: the rate at which a deformed material
goes back to its undeformed condition after the
applied force is removed.
• Adhesiveness: the work necessary to overcome
the attractive force between the surface of the
food and the other surface of contact (e.g.,
tongue, teeth, etc.)
Textural Characteristics
• Brittleness: the force with which the
material fractures and was related to the
primary parameters of hardness and
cohesiveness.
• Chewiness: the energy required to
masticate a solid food product to a state
ready for swallowing and was related to
hardness, cohesiveness, and elasticity.
• Gumminess: the force required to
disintegrate a semisolid food to a state
ready for swallowing and was related to
hardness and cohesiveness.
Example Textural Profile
TPA
Texture Profile Analysis
• Hardness = Maximum force from First Stoke (N)
• Fracturability or Brittleness = Maximum force of the first
peak from First Stoke (N)
TPA
Hardness
Fracturability
Cohesiveness= A2/A1
A1
A2
TPA
Springiness= L2
Springiness Index= L1/L2
L3
L1
L2
TPA
TPA
Application for Packaging
• Tension Test
• Compression Test
• Peel Test
• Tear Test
• Friction Test
• Dart Drop Impact Test
VITAMIN BOTTLE
SYRINGE
PULL TAB CANNISTER
FOOD BOX TOP
CRACKER JACKS
Compression Test
Peeling Cup
Universal Testing Machine