imaging technology: what can it tell you about your product? · imaging technology: what can it...

Imaging technology:

what can it tell you about

your product?

Martin Whitworth

Campden BRI Day 2017

Imaging applications

• Online process control

– Machine vision

– Product inspection

– Sorting

• Product characterisation

– Documentation and

specification of appearance

– Revealing the invisible

– Image analysis: colour, size,

shape, structure etc.

Food appearance

• Colour

• Size, shape

• Gloss, texture,

uniformity

Calibrated colour

imaging • Calibrated: Suitable for

colour measurement

• Consistent: Documentation

of trial product appearance

• Accurate reproduction:

Reference charts

Application for specifications

Case study • Retailer and poultry suppliers visited with

example products.

• Limits agreed for visual characteristics.

• Campden BRI produced charts using accurate

images of the agreed product examples.

Foreign body identification Multi-laminate film

50 μm

PE Al PE PET

Layers identified by

FT-IR spectroscopy

200 μm

Metal

fleck on

sugar Identified as

copper by X-

ray spectrum

Human

hair

Rabbit

hair/fur

Particle size and shape • Several methods available

• Dynamic image analysis

– Grain, seeds, ground

materials, powders,

particles in liquid

suspension...

– Size and shape

Dynamic image analysis

Laser diffraction

Dynamic light scattering

ESZT

Sieving

1μm 1mm 1nm

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

De

nsity d

istr

ibu

tio

n q

0*

1 2 3 4 5 6 7 8 9 10

Width / mm

Width

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

De

nsity d

istr

ibu

tio

n q

0*

1 2 3 4 5 6 7 8 9 10

Length / mm

Length

Thermal imaging

• Development and

validation of cooking and

reheating instructions

• Instructions validated for

a range of typical ovens.

• Enables hot and cold

spots to be identified

– To ensure product is

cooked throughout

– To avoid excessive

temperatures for

packaging

Microwave heating of product in

plastic pot without stirring

20

40

60

°C 78°C

NIR hyperspectral imaging • Mapping of composition

• Rapid (a few seconds)

• Also suitable for online use

0 min 1 min 4 min 7 min 14 min Frying

time

Example: Fat in chips

Chocolate bars • NIR absorbance

bands provide

information on

composition

• Differences

apparent

• Quantitative

measurements

possible with

calibration.

Moisture (OH)

Crystalline sucrose

Fat (CH2)

Low High

Chocolate

Biscuit Structure

revealed

Moisture distribution

• Effect of baking

• Storage trials for migration over shelf life

Biscuit baking

Dough

Moisture (%)

Biscuit

Bread staling

Fresh Stale

Product structure • C-Cell instrument for bread

quality assessment

• Developed at Campden BRI

Control: Chorleywood process

Radical process

C-Cell contrast:

0.7895 ± 0.005 0.832 ± 0.008

Case study:

Radical bread process • Softer, finer

structure

• C-Cell data used

in support of

patent claims

Structure formation during

baking • X-ray CT scanning

• Oven placed inside

scanner

Structure during baking

Fruit

cakes

Muffins

Croissants

Control +DATEM +Lipase

Case study: Lipid ingredients • Improve bread volume and structure.

• Tested hypothesis for clients about the stages

at which they affect the structure.

X-ray micro CT • High resolution, non-destructive 3D imaging

X-ray micro CT

Barley malt

Cake

Plastic

bottle

cap

Chocolate - with aerated filling

0.0

0.2

0.4

0.6

0.8

1.0

0 1 2 3

Vo

lum

e (

%)

Diameter (mm)

Bubble size

distribution

1.2 1.7

2.3

3.9 Porosity

(%)

Total: 9.1

Imaging technology: what can

it tell you about your product?

• Documentation and specification of

appearance (calibrated colour imaging)

• Particle size and shape

• Foreign body identification (microscopy)

• Temperature uniformity (thermal imaging)

• Mapping composition (NIR, FTIR, X-ray)

• Structure measurement (X-ray micro-CT)

Martin.Whitworth@campdenbri.co.uk