1Kutu,M.M., 2Hugo,A.,3Zondagh,I.B.,3Van Heerden,S.M.,3Calitz, F.J. and 1Jooste, P.J 1Faculty of Science, Department of Biotechnology and Food Technology

2University of the Free State and 3Agricultural Research Council

THE SENSORY AND PHYSICAL PROPERTIES

OF FROZEN CHICKEN BREASTS INJECTED AT

FIVE DIFFERENT INJECTION LEVELS WITH VARIOUS BRINE FORMULATIONS

SAAFoST 2015 Congress

08 September 2015 – Maphuti Kutu

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Presentation outline

Introduction

Aim of the project

Experimental methods

Results and discussions

Conclusion

Acknowledgements

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Introduction Annual per capita consumption of poultry meat in South Africa

increased from 14.10kg in 1981 to 35.79kg in 2012

Brine – solution of water and brine - and other functional

ingredients/additives

Brine injection - enhancement, marination, treatment with added

solutions

The basic ingredients of injectable brines are water, salt and

phosphates combined with various other ingredients

Advantages - improved yield to the processor and improved products

to the consumer.

(Smith & Acton, 2001; Feiner, 2006; Alvarado & McKee, 2007; DoH, 2010; Abstract of

Agricultural Statistics, 2013)

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Background – “Botox”

chicken portions

Poultry brine injection

survey

Phase 1 - Excessive levels

of brine injection

High thawing and cooking

loss

Adulteration vs Value adding

(Moholisa,2011)

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FOTO

Background – current legislation

Live receiving

unloading

Evisceration

Chilling (4% or less

moisture pick up)

Injection (4% or less

moisture pick up)

Total = 8%

m/m

(DAFF, 1992)

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The injection technology

)

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Project & Google pics

Presentation outline

Introduction

Aim of the project

Experimental methods

Results and discussions

Conclusion

Acknowledgements

7

Aim of the project

The aim of this study was to determine the effect of brine

composition and injection level on the sensory and

physical properties of frozen chicken meat.

Specific objectives: To determine the sensory properties

(tenderness and flavour) as well as physical textural

properties of brine injected frozen chicken meat obtained

from ~36-day old birds. The thawing and cooking loss of

the cooked chicken were also determined.

Conducted mainly at the Agricultural Research Council

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Presentation outline

Introduction

Aim of the project

Experimental methods

Results and discussions

Conclusion

Acknowledgements

9

Experimental design

Samples:

90 Fresh, air-chilled chicken breasts (dissected from

whole birds), purchased from a local abattoir

Brine solutions: 3 different brine formulations

i) NaCl – salt & water only

ii) STPP – salt, water & phosphate

iii) Cocktail – salt, water, phosphate, dextrose &

hydrocolloids (xanthan gum & carrageenan)

N:B All formulated for specific injection levels

5 replications done

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Experimental design

- Flow diagram

CONTROL SAMPLES (BREASTS)

*SAMPLES TO BE INJECTED (BREASTS

BRINE SOLUTIONS (NaCl, STPP,

Cocktail)

WEIGHING

INJECTING

FREEZING (N2 )

RE-WEIGHING & PACKAGING STORE IN FREEZER

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Presentation outline

Introduction

Aim of the project

Experimental methods

Results and discussions

Conclusion

Acknowledgements

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Results - Cooking data

Higher moisture losses during thawing and cooking at

higher injection levels (30% & 60% m/m)

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Results - Sensory evaluation

Although the difference between the control and injected treatments

was clearly detected in all sensory attributes, the difference between

different injection levels was mostly not significant

Similar results were found by Desmond et al. (2002) on ham joints - that the

detection of differences in sensory properties between different injection levels as

far apart as 10% proved to be a challenge even for trained panellists

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Results - Sensory evaluation (cont.)

As expected, the higher levels of injection were generally

significantly juicier than the lower levels.

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Results -Texture determination (Tenderness)–

Instron shear force resistance measurements

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The chicken breast from the commercially available broilers were found to

be very tender even before injection with brine i.e. 2.27 kg-force

Shear force measurements of 0-3kg-f are regarded as very tender

Lyon et al. (1998)

Results - Sensory tenderness

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Presentation outline

Introduction

Aim of the project

Experimental methods

Results and discussions

Conclusion

Acknowledgements

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Conclusions

The lower injection levels (5% and 10% m/m) can

achieve beneficial outcomes in terms of both the

improved sensory properties and minimal thawing and

cooking losses.

Un-injected chicken breasts obtained from birds sold

commercially in South Africa are still very tender.

Brine injection, especially at high injection levels (m/m) is not

justified with regard to improving the physical texture

(tenderness) of chicken meat.

Recommended regulatory measure - Low levels of

injection 5% and10% including extraneous water (i.e.

<10%) m/m)

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Presentation outline

Introduction

Aim of the project

Experimental methods

Results and discussions

Conclusion

Acknowledgements

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Acknowledgements

• Department f Agriculture, Forestry and Fisheries

• Agricultural Research Council

• Supervisors:

– Prof Piet Jooste (TUT)

– Dr Beryl Zondagh (ARC – retired)

– Prof Arno Hugo (UFS)

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THANK YOUU

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