formation in cheese of the eye and control Mechanism

Federal Department of Economic Affairs, Education and Research EAER

Agroscope, Inst. for Food Sciences IFS

IDF Cheese Science & Technology 2016, Dublin

Mechanism and control of the eye

formation in cheese

Dominik Guggisberg

Agroscope, Institute for Food Sciences (IFS)

Bern-Liebefeld, Switzerland

2 Mechanism and control of the eye formation in cheese

Overview

 Importance of eye formation in cheese

 Imaging methods (sectional image, X-ray, CT, ultrasound)

 Eye formation: influencing factors and theory

 Eye formation experiments

 Eye defects

 Conclusions

Significance of eye formation

4 Mechanism and control of the eye formation in cheese

Imaging methods

 Sectional views

 X-ray

 Ultrasound echolocation (Albrecht 1998)

 Computed tomography (Strand 1985)

2D and 3D views from CT-scans

Excessive eye formation Sparse eye formation

6 Mechanism and control of the eye formation in cheese

Validation of the CT method

CO ₂ PRODUCING CULTURE (SATURATION OF CHEESE)

NUCLEI

EYE FORMATION

Eye formation:

Theory and influencing factors

CO ₂ DIFFUSION

CO ₂ DIFFUSION RIND, FOIL,…

8 Mechanism and control of the eye formation in cheese

Improved hygiene in milk production

Times are changing…

 First scientific hypothesis (beginning of 20 ^th century):

 «gas-building colonies», punctual oversaturation of CO ₂

 Clark (Review, 1917):

 Differences in CO ₂ concentration are balanced by diffusion

 Eyes are formed at “favoured localities”

 Crystallisation  “seeds”, “irregularities”

 Rain drops  “dust particles”

 Gehriger (FAM, 1970): Production in winter: more eyes, production in summer: less eyes

 Review Martley and Crow (1996):

 microscopically small air bubbles

 Review Polychroniadou (2001)

 Nitrogen gas in the milk, CO ₂ produced from starters

History eye formation (nucleus-theory)

10 Mechanism and control of the eye formation in cheese

Further theories:

  Micro-particles

 small mechanical openings (technical eye formation)

 Fragnière (Agroscope, 2004)

 Micro-filtration disables eye formation

 Agroscope (2013 - 2015):

 Hay particles and eye formation are related and define the starting point of the eye formation (Structural element as an indication!)

20 µm

Cavities in hay

particles allow

eye seeding

Control: 10 eyes 0.063 mg: 52 eyes 0.125 mg: 84 eyes 0.25 mg: 178 eyes

0.5 mg: 184 eyes 1 mg: 359 eyes 2 mg: 447 eyes 4 mg: 738 eyes

Control of eye formation

60 days

12 Mechanism and control of the eye formation in cheese

Guggisberg et al., IDJ, 2015

Control of eye formation

130 days

Control

0.06mg

0.12mg

0.25mg

0.5mg

1.0mg

2.0mg

4.0mg

Nu m b er o f cheese ey es [ -]

Hay powder addition [mg/90L milk]

y = 164.96ln(x) + 422.84 R² = 0.8846

0 100 200 300 400 500 600 700 800 900

0 0.5 1 1.5 2 2.5 3 3.5 4

Nu mber of che es eye s [ -]

Dose response effect of hay particles

45 days

Hay powder addition [mg/90 L milk]

14 Mechanism and control of the eye formation in cheese

 Vegetable particles from storage tissue are ineffective

 Processed cellulose- and wheat fibres have no effect

day 1

day 2

Hay particles

Hay particles

Potato flour

Potato flour

Ginger particles

Ginger particles

Wheat fibres

Wheat fibres

Influence of the botanical origin

 Very efficient (2 mg / 90 L)

 reproducible control of eye formation

day 1

day 2

Particles from stems and leaf tissue

Hay particles

Hay particles Red clover particles

Red clover particles Maté tea particles Thyme particles

Thyme particles

Maté tea particles

16 Mechanism and control of the eye formation in cheese

0 2 4 6

0 50 100

R ela tiv e e ye v olum e [%]

Ripening time [days]

4 2 1 0.5 0.25 0.125 0.0625 0

Increase in eye volume during ripening

warm room storage cool room storage

0 2 4 6

0 50 100

R ela ti ve ey e v olume [%]

Ripening time [days]

4 mg/90 L

Control

Day 45

Day 60

Day130

Eye defects: Crack formation

18 Mechanism and control of the eye formation in cheese

Conclusions

Process control Number of eyes 

Approx. eye volume  Cheese quality 

Understanding eye defects

20 µm

Mechanism of eye formation

• Daniel Wechsler

• Philipp Schütz (HSLU)

• Marie-Therese Fröhlich-Wyder

• Walter Bisig

• Stefan Irmler

• Ernst Jakob

• René Badertscher & Team

• Ruedi Amrein

• Hans Winkler

• Daniel Goy

• Karl Schafroth

• Martin Anderegg

• Florian Loosli

• Thomas Theiler (FOPH)

• Johan Lang (University Bern)

• …

Thanks

20 Mechanism and control of the eye formation in cheese

Thank you for your attention

Agroscope good food, healthy environment