the sensory and physical properties of frozen … · the basic ingredients of injectable brines are...
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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
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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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