View
0
Download
0
Category
Preview:
Citation preview
Instrumental Detection of Boar Taint:Advantages and Disadvantages of the Existing
Methods
Professor Olena Doran University of the West of England, Bristol, UK
TRAINING SCHOOLSensory evaluation of boar taint: Methods for assessor selection, good sensory practice
and performance evaluation
Boar Taint
An offensive odour in the meat of
5-10% of uncastrated male pigs
Is mainly due to excessive
accumulation of skatole and
androstenone in pig adipose
tissue
Threshold levels differ between countries Skatole: 0.20-0.25 µg/g of fat
Androstenone: 0.5 - 1.0 µg/g of fat
EU position
EU Directive on castration without anesthesia
during the first week of life (2001/93/EC)
Plan to voluntarily end surgical castration
(EU SANCO, 2010)
European Partnership on Alternatives to
Surgical Castration of Pigs Established
(hedhttp://ec.europa.eu/food/animal/welfar)
Potential solutions
• Alternatives to surgical castration to
prevent boar taint
• Technologies for rapid detection
of boar taint
• Effective meat processing technologies
Prevention of
Boar Taint
Surgical
Castration
Immunocastration
Management/Diet
Genetic
selection
Semen Sorting
Slaughtering at
Lower weight
“There are no harmonised methods of consistently
identifying carcases with boar taint in commercial
slaughter houses. Investigation of possible
processing techniques to reduce the offensive
properties of boar taint is hampered by the lack of
such methods to asses levels of the compounds
contributing to the phenomenon”(The EFSA Journal, European Food Safety Authority, 2004)
Recent initiatives
EU ALCASDE Project “Study on the improved methods for animal-
friendly production, in particular on alternatives to the castration of
pigs and on alternatives to the dehorning of cattle”
EU: Health and Consumers Directorate General Tender “Study on
rapid detection methods for boar taint used or being developed at
slaughter plants in the European Union”
“UK/China partnership for innovative technologies”.
EU COST ACTION (CA15215) Innovative Approaches for
Pork Production with Entire Males (IPEMA)
Detection of Skatole and Indole
Colorimetric method
Gas Chromatography
(GC)
High Performance
Liquid Chromatography
(HPLC)
Mass-Spectrometry
” Bio-sensors
Detection of Androstenone
Gas Chromatography
(GC)
Mass-Spectrometry
Immunoassay/
Radioimmunoassay
Colorimetricmethod
Bio-sensors
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
Principle of Colorimetric Method
Image from:
https://www.google.co.uk/search?biw=911&bih=449&tbm=isch&sa=1&ei=XmC4W4nbCIvAgAam877QCw&q=colo
rimeter+principle&oq=colorimeter+principle&gs_
Colorimetric method Quantification of skatole equivalent in adipose tissue
(Mortensen and Sorensen 1984)
Determination of total 16-androstenes in fat (Squires, 1990)
Implemented in Danish slaughter houses for detection of
skatole (automated system) in 1990s
https://www.google.co.uk/search?q=danish+slaughterhouse+boa
r+taint+detection
Colorimetric Method
Advantages
• On-line method for skatole
• Simple
• Capacity: 200 samples/h
• Limit of detection: 0.03 µg/g
“skatole equivalent”
• Time between sampling and
results: 20 min
• High correlation with sensory and
HPLC results
Challenges
• Specificity issues:
-“skatole equivalent”
- total 16-androstene steroids
• Requires extraction stage
• Analysis Time?
• Existing on-line method does not
detect androstenone
• Interference of cholesterol with
androstenone detection
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
Principle of Gas Chromatography
https://www.youtube.com/watch?v=NUVbIClAYUY
Gas Chromatography Detection of androstenone of skatole in adipose tissue
(Claus, 1970)
Analysis of skatole concentration in backfat (Vold, 1970)
Coupling of Chromatography with:
-Mass-Spectrometry,MS
(Garcia-Regueiro and Rius, 1995, Schreurs et al., 2007;
Verplanken et al, 2016)
-Flame Ionisation Detector, FID
(Hansson et al., 1980;Porter et al., 1989)
-Nitrogen-phosphorus detector, NPD
(Peleran and Bories, 1985; Zaboloysky et al., 1995)
Gas Chromatography
Advantages
• Sensitive
• Short analysis time for skatole
(around 10 min) after samples
preparation
• Simultaneous detection of boar
taint compounds (when coupled
with mass spectrometry)
• Can be portable (when coupled
with mass spectrometry)
Challenges
• Time-consuming samples
preparation stage
• Expensive
• Portable GC-MS does not achieve
threshold detection of boar taint
compounds
• Laboratory method
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
Principle of High Performance Liquid
Chromatography (HPLC)
http://www.waters.com/waters/en_
GB/How-Does-High-Performance-Liquid-Chromatography
-Work%3F/nav.htm?cid=10049055&locale=en_GB
HPLC Detection and quantification of skatole and indole
Coupling of HPLC with:
• UV-detector (Garcia-Regueiro and Diaz, 1989)
• Fluorescent detector, FL
(Givis et al., 1991; Hansen-Moller, 1992, Garcia-Regueiro and Rius, 1998)
• Mass-spectrometry (Bekaert et al. 2012)
HPLC-FL method for androstenone detection
(Claus et al., 1997)
HPLC
Advantages
• High sensitivity
• High specificity
• High reproducibility
• Potential of simultaneous
detection of skatole, androstenone
and indole
Challenges
• Samples preparation stage
• Laboratory-based method
• Expensive
• Long analysis time
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
Principle of Mass-Spectrometry
https://chem.libretexts.org/Textbook_Maps/Analytical_Chemistry/Supplemental_Modules_(Analytical_Chemistry)
Mass-Spectrometry
Detection and quantification of androstenone
(in combination with separation methods e.g. liquid or gas
chromatography)
(Garcia-Regueiro and Diaz, 1989;Schilt et al, 1989;
Verheyden et al., 2007; Verplanken et al., 2016)
Detection of indolic compounds
(Zamaratskaia and Jastrebova, 2006)
Simultaneous measurement of all the boar taint
compounds(Verheyden et al., 2007)
Mass-Spectrometry
Advantages
• Enhancing specificity of
detection
• High sensitivity
• Possibility of simultaneous
analysis of boar taint
compounds
Challenges
• Used as a part of a complex
approach together with separation
methods
• Expensive
• Require specialised staff
• Long analysis time
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
Immunoassay
• The analyte reacts with specific antibody
• The complex is detected and quantified by a range of approaches
(e.g. radioactive isotopes, enzymes)
https://www.bio-rad-antibodies.com/elisa-types-direct-indirect-
sandwich-competition-elisa-formats.html
Immunoassays
Detection and quantification of androstenone(Kaufmann and Schubert, 1986; Claus, Mahler and Munster, 1988, Tuomola et al.,
2002)
- enzyme immunoassay
- radioimmunoassay
- fluoroimmunoassay
Limited information on the use of immunoassays for
analysis of skatole (Tuomola et al., 2000)
Immunoassay
Advantages
• Easy to perform
• Accurate and sensitive
(radioimmunoassay)
Challenges
• Selectivity/Antibody specificity
• The use of radioactive isotopes:
- Require specialised laboratories
- Not suitable for the use in
abattoirs
- Expensive
Methods to be discussed
Colorimetric method
Gas chromatography (GC)
High Performance Liquid Chromatography
(HPLC)
Mass-spectrometry
Immunoassay/radio immunoassay
Bio-sensors
http://www.biosensores.com/EN/biosensores_afinidad_molecular.php
Bio-sensors based on the use of insects
Wasps can be conditioned to respond to low, medium
and high concentration of indole, skatole and androstenone
in boar fat
(D.Olson, F. Wackers, H.-E.Haugen, 2012)
Types of
bio-sensors
Bioluminescent
Bacteria-based
biosensors
Nano particles-
based sensors
Gas sensors
Optical
biosensors
Electrochemical
biosensors
Gas Sensors
Screen-printed Electrodes(Prof. John Hart and his group, UWE)
•Rapid
•Multi-analyte capability
•Inexpensive fabrication
Technology for Boar Taint (Inventors: J. Hart, A. Crew, O. Doran, N. McGuire, UWE)
• Simultaneous analysis of skatole and androstenone
• Can be extended to analysis of other compounds
• Cost effective
• Does not require sample preparation
• Displays results within seconds as numbers
• Can be portable
• Can apply to analysis of boar taint in:
?
Challenges
• Incorporating in abattoir setting
• Different needs and specifications for small and
large abattoirs (e.g. hand-held or stationary device)
• Analysis time – to reduce further?
• Potential to use multiple equipment units to speed
up the analysis
• Cost will depend on the scale of production
Conclusions
EU legislations and initiatives emphasise the need in on-
line detection of boar taint
There is a number of instrumental methods for boar taint
compounds detection but not for on-line measurement
(except of colorimetric detection of skatole)
A number of technologies for on-line boar taint detection
are at various stages of development. Evaluation in
industrial setting is essential.
Harmonization of existing methods for boar taint detection
is required
4. ReferencesAmpuero, S.K., Verkuylen, B., Dahlmans, H., Hortos, M., García-Regueiro, J.A., Dahl, E., Odresen, O., Feitsma, H., Mathur, P.K.,
Harlizius, B., 2011. Inter-laboratory comparison of methods to measure androstenone in pork fat. Animal, 5(10): 1-9.
Bekaert, K. (2013). Chemical and sensory detection of boar taint. Doctor in Veterinary Science, Ghent University.
G.Backus, 2017. Human nose scoring System for boar taint. Prague. Cost IPEMA (February 2017). http://www.ca-ipema.eu/meat-quality
Haugen, J. E., C. Brunius and G. Zamaratskaia (2012). "Review of analytical methods to measure boar taint compounds in porcine adipose tissue: The need for harmonised methods." Meat Science 90(1): 9-19.
Haugen, J.E., Panella-Riera, N., de la Calle, B. 2013. D1.1. Method survey. Boarcheck project. D1.1 Method survey
Keller, A., Zhuang, H., Chi, Q., Vosshall, L. B., & Matsunami, H. (2007). Genetic variation in a human odorant receptor alters odourperception. Nature, 449(7161), 468–472.
Liu, X., H. Schmidt and D. Mörlein (2016). "Feasibility of boar taint classification using a portable Raman device." Meat Science 116: 133-139.
Mathur PK, Napel J ten, Crump RE, Mulder HA, Knol EF. Genetic relationship between boar taint compounds, human nose scores, and reproduction traits in pigs. J Anim Sci. 2013;91(9):4080–9. DOI: 10.2527/jas.2013-6478.
Mathur, P. K., J. ten Napel, S. Bloemhof, L. Heres, E. F. Knol and H. A. Mulder (2012). "A human nose scoring system for boar taint and its relationship with androstenone and skatole." Meat Science 91(4): 414-422.
Sorensen, K. M., C. Westley, R. Goodacre and S. B. Engelsen (2015). "Simultaneous quantification of the boar-taint compoundsskatole and androstenone by surface-enhanced Raman scattering (SERS) and multivariate data analysis " Analytical and Bioanalytical chemistry: 10.
Trautmann, J., J. Gertheiss, M. Wicke and D. Mörlein (2014). "How olfactory acuity affects the sensory assessment of boar fat: A proposal for quantification." Meat Science 98(2): 255-262.
Wang, Q., S. Ding, K. Hamouche and C. Yu (2014). Evaluating meat quality using Ramman Spectroscopy. Proceedings International Converence of Agricultural Engineering, Zurich.
Maria Font i Furnols
IRTA- Monells
Consumer studies and alignment consumer acceptance and panelist
Training school “Sensory evaluation of boar taint: methods for assessor selection, good sensory practice and performance
evaluation
IPEMA- CA15215
Innovative approaches in pork production with entire males
SENSORY ANALYSIS
SENSORY EVALUATION IS A SCIENTIFIC
DISCIPLINE USED TO EVOKE, MEASURE,
ANALYSE AND INTERPRET HUMAN
REACTIONS AND SENSATIONS TO THOSE
CHARACTERISTICS OF FOODS,
BEVERAGES AND MATERIALS AS THEY ARE
PERCEIVED BY THE SENSES OF SIGHT,
SMELL, TASTE, TOUCH AND HEARING
(IFT Sensory Evaluation, 1975)
SENSORY ANALYSIS: IMPORTANT CONCEPTS
ANALYTICAL SENSORY ANALYSIS VS. CONSUMER STUDIES
Selected and trained people (panelists)
Evaluations totally OBJECTIVES and reproducible
They do not use hedonic works or preference
Comparable to a laboratory equipment
Comparison between sensory and instrumental analyses
VerificationReadjustment
CALIBRATION
SELECTION
Completion of the methodology:- references- sample preparation- ...
Training of the group:- use of scales- definition of attributes- ...
Recruitment:
- availability
- interest & motivation
- …
Time T Time T
- New accessories- Replace part of old or broken pieces
- Experience- Replacement of tasters
Previous information:- characteristics- price
- ...
OBJECTIVE AND REPEATABLE
MEASURE
SENSORY ANALYSIS: IMPORTANT CONCEPTS
ANALYTICAL SENSORY ANALYSIS VS. CONSUMER STUDIES
They represent a specific population
Their evaluations are SUBJETIVES
The use words like good, bad, satisfaction,…
Selected and trained people (panelists)
Evaluations totally OBJECTIVES and reproducible
They do not use hedonic works or preference
Comparable to a laboratory equipment
Example of the difference between tasters and consumers
Fictitious study about different alcoholic drinks
Russianconsumers
Cubanconsumers
Spanishconsumers
Scottishpanel
Russianpanel
Cubanpanel
Spanishpanel
Whisky
Vodka
Rum
Wine
Prefer
Prefer
Prefer
Prefer
Sweettaste
3/10
1/10
5/10
2/10
Intensity
Subjective measurement,
indicates preference or acceptability
Objective measurement, neverindicates preference
Scottishconsumers
Consumerbehaviour
Psychologicalfactors
Lifestyle andvalues
Expectations
Risk
Attitude
Socio-culturaleffect
Beliefs
Moral and affectivecomponent
Origin
Sensoryfactors
Visualappearance
In-mouthtexture
Flavour
Odour
Marketingfactors
Price
Brand
Availability
Label
Individual Product-specific
Environmental
Font-i-Furnols & Guerrero, 2012
DESIGN OF SENSORY STUDIES
• PRODUCT / MUSCLE EVALUATED
TYPE OF PRODUCT
N=50
Font-i-Furnols, 2012
DESIGN OF SENSORY STUDIES
• METHODOLOGY USED IN SAMPLE PREPARATION
• PRODUCT / MUSCLE EVALUATED
TÍTOL DEL
POWER POINT.
PRESENTACIÓ
COOKING METHOD & TEMPERATURE
Dry-heat
Stewed +
oven
Marinated &
Stewed +
oven
Microwave
Hotwire
Melting
Boiling -75º
Boiling- 25º
Un/pumped
Fry-Grill
Oven
Hot plate
70 & 80ºC
65ºC
72.5ºC
80ºC
SM - LD
68 & 80ºC
Sir
ete
t a
l
19
97
McC
au
ley e
t a
l.1
99
7W
hittin
gto
n e
t a
l. 2
01
1P
resta
te
t a
l.
20
02
Woo
d e
t a
l.
Nute
et a
l.,
19
95
Ag
erh
em
,
To
rnb
erg
,
19
95
DESIGN OF SENSORY STUDIES
• METHODOLOGY TO DETERMINE BOAR TAINT COMPOUNDS
• TYPE OF SAMPLES (SEX, AND & SKA LEVELS,…)
• QUESTIONNAIRE: ATTRIBUTES AND SCALE
• SENSITIVITY TO ANDROSTENONE
• PRODUCT / MUSCLE EVALUATED
• METHODOLOGY USED IN SAMPLE PREPARATION
SENSITIVITY TO ANDROSTENONE
Different methods to determine consumer sensitivity:
DESIGN OF SENSORY STUDIES
• METHODOLOGY TO DETERMINE BOAR TAINT COMPOUNDS
• TYPE OF SAMPLES (SEX, AND & SKA LEVELS,…)
• QUESTIONNAIRE: ATTRIBUTES AND SCALE
• SENSITIVITY TO ANDROSTENONE
• PRODUCT / MUSCLE EVALUATED
• METHODOLOGY USED IN SAMPLE PREPARATION
• PRESENTATION OF RESULTS AND DATA ANALYSIS
• CONSUMER’S PROFILE
• INFORMATION PROVIDED TO THE CONSUMERS
• TEST LOCATION: home test, hall test
-Controlled conditions
-Less consumers and samples
-All the questionnaires recovered
-Less similar to consumption reality
-High variability in pork preparation
-Need of more consumers & samples
-Low-medium % returned questionnaires
-Conditions close to consumption reality
What is the best? Depends on the objectives of the study
Comparison, cross-cultural studies,…at same conditions
Enhance the problem
‘Real’ situation
HOME TEST HALL TEST
TEST LOCATION: HOME TEST vs HALL TEST
SENSORY STUDIES ON BOAR TAINT:
SENSITIVITY OF THE CONSUMERS
CONSUMERS + TRAINED PANEL
Sensitivity to Androstenone
Germany: Highly sensitives Midly sensitives Insensitives
. Men 15.6 14.7 69.7
. Women 19.3 14.7 65.9
. Total 17.6 14.7 67.7
Spain: Highly sensitives Midly sensitives Insensitives
. Men 23.7 16.6 59.7
. Women 37.3 14.6 48.1
. Total 30.9 15.5 53.6
(Weiler et al., 2000)
ODOUR Highly sensitive Less sensitive/insensitive Sign. of sensitivity
Spain
Low 4.10a 4.15 NS
Medium 3.78b 4.22 **
High 3.75b 4.12 ***
FLAVOUR Highly sensitive Less sensitive/insensitive Sign. of sensitivity
Germany
Low 4.68a 4.75 NS
Medium 4.41ab 4.62 NS
High 4.17b 4.66 ***
(Weiler et al., 2000)1: Dislike extremely7: Like extremely
AND Flavour Odour
Like 3.75a 3.35a
Indifferent 3.35b 3.06b
Dislike 3.39b 2.94b
1: Dislike extremely7: Like extremely
35 EM, 23 CM, 36 IM and 24 FE Pi x (DU x LR). Slaughtering: 180 days, same age Efficacy vaccine, 100%
# Loins defrozen (24 h at 4ºC)
SAMPLE PREPARATION - panellists
ANALYTICAL SENSORY ANALYSIS: METHODOLOGY
Font i Furnols et al. (2009)
• Cooked inside glass tubes
• Convection oven, 10 minutes at 180ºC
SAMPLE PREPARATION - panellists
ANALYTICAL SENSORY ANALYSIS: METHODOLOGY
Font i Furnols et al. (2009)
EXPERIMENTAL DESIGN• 8 trained panellists
• 24 sessions (4 samples/session, one of each typee)
• Order of presentation different for each panellist to avoid first sample
and carry over effect)
ODOUR
Androstenone
Skatole
Sweet
Grilled
FLAVOUR
Androstenone
Skatole
Sweet
Metallic
TEXTURE
Hardness
Juiciness
ANALYTICAL SENSORY ANALYSIS: METHODOLOGY
0
2.5
5
O Androstenon
O Escatol
O Dulce
O Tostado
F Androstenon
F Escatol
F Dulce
F Metálico
T Dureza
T Jugosidad
Castrados Inmunocastrados Enteros Hembras
a
a
O skatole
O sweet
O grilled
F androstenone
F skatole
F sweet
F metallic
T hardness
T juiciness
O androstenone
Immunocastrated malesCastrated males Entire male Females
ANALYTICAL SENSORY ANALYSIS: RESULTS
Font i Furnols et al. (2009)
CONCLUSIONS
The meat from immunocastrated males is sensory different
from those of entire males, but it is not different from those of
castrated males and females.
The meat from entire males is characterized by an odour and
flavour of androstenone and skatole
ANALYTICAL SENSORY ANALYSIS: RESULTS
Font i Furnols et al. (2009)
# Loin defrost 24 h at a temperature of 4ºC
SAMPLE PREPARATION - consumers
CONSUMERS: METHODOLOGY
Font i Furnols et al. (2008)
Cook: 180ºC
10 minutes
Convection oven (FAGOR)
SAMPLE PREPARATION - consumers
CONSUMERS: METHODOLOGY
Font i Furnols et al. (2008)
EXPERIMENTAL DESIGN• Controlled conditions at IRTA-Monells (Hall test)
• 20 sessions of 10 consumers
• Ordre of presentation of the samples different for each consumer
(in order to avoid first sample and carry-over effect)
• 4 samples/consumer 80 samples, 20/sex type
• 201 representative consumers (gender, age)
97104201Total (n)
48.351.7100.0Total (%)
18.616.417.461-77 years old
35.130.832.841-60 years old
32.033.732.816-40 years old
14.419.216.918-25 years old
Age WomenMenGlobal
%
CONSUMERS: METHODOLOGY
Font i Furnols et al. (2008)
QUESTIONNAIRE
I like it extremely . . . . . . . . . . . . . . . . . . . . . . . . ___________________
I like it a lot . . . . . . .. . . . . . . . . . . . . . . . . . . . . . ___________________
I like it . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . ___________________
I like it slightly . . . . . . . . . . . . . . . . . . . . . . . . . . ___________________
I dislike it slightly . . . . . . . . . . . . . . . . . . . . . . . ____________________
I dislike it . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ____________________
I dislike it a lot . . . . . . . . . . . . . . . . . . . . . . . . . . ____________________
I dislike it extremely . . . .. . . . . . . . . . . . . . . . . . ____________________
Sample Nº:_________ ODOUR FLAVOUR OBSERVATIONS
9
8
7
6
4
3
2
1
CONSUMERS: METHODOLOGY
6.2a5.8b6.4a6.4a201Flavour
6.2a5.5b6.2a6.2a201Odour
Only entire males with < 1 μg/g of androstenone
6.2a5.7b6.4a6.4a201Flavour
6.2a5.4b6.2a6.2a201Odour
All the animals
FEEMIMCMN
6.2ab5.9b6.4a6.4a201Flavour
6.25.86.26.2201Odour
Only entire males with < 0.5 μg/g of androstenone
1 N=171 for EM; 2 N=82 for EM
CONSUMERS: RESULTS
Font i Furnols et al. (2008)
SENSIBILITY TO ANDROSTENONE SMELL• Consumers’ sensitivity test to pure androstenone smell
Highly sensitive
Less sensitive/insensitive
6- Extremely strong
5- Very strong
4- Strong
3- Weak
2- Very weak
1- Extremely weak
0- No odour percetion
Total (n) Sensitive (%)Less sensitive/insensitive
(%)
Men 104 36.5 63.5
Women 97 53.6 46.4
CONSUMERS: METHODOLOGY
ODOUR ACCEPTABILITY
4
5
6
7
CM IM EM FE
Oo
du
rsco
re
a a
b
a
Global
a a
b
a
Sensitive Less sensitive/insensitive
CONSUMERS: RESULTS
a a
b
a
aa
b
a
4
5
6
7
CM IM EM FE
Fla
vour
score
s
Global Sensitive Less sensitive/insensitive
FLAVOUR ACCEPTABILITY
CONSUMERS: RESULTS
This study shows that:
Consumers’ acceptability of pork depends on the sex of the
animals: consumers prefer the odour and the flavour of pork from
females, surgically castrated males and immunocastrated males
compared with those from entire males.
The acceptability of pork by consumers sensitive to
androstenone is more affected by the sex of the animal for
consumers sensitive to androstenone than for consumers less
sensitive or insensitve to this compound.
Pork from entire males is less preferred than those from
surgically castrated males, immunocastrated males and females,
also if the levels of androstenone are low.
CONSUMERS: CONCLUSIONS
Font i Furnols et al. (2008)
CORRELATIONS: PANEL-CONSUMERS-CHEMICAL
OAnd OSka FAnd FSka And Ska
Flavour
accept
O Skatole 0.68 -
F Androstenone 0.91 0.61 -
F Skatole 0.80 0.67 0.75 -
Androstenone 0.88 0.59 0.95 0.73 -
Skatole 0.57 0.53 0.56 0.65 0.53 -
Flavour accept -0.46 -0.22 -0.42 -0.42 -0.42 -0.26 -
Odour accept -0.50 -0.26 -0.49 -0.44 -0.49 -0.35 0.77
Font i Furnols et al. (2009)
F_OGen M_Ogen M_FLGen Cons_Od Cons_Flav Hot Iron
Andros 0.18 0.35 0.32 0.19 0.30
Skatole 0.28 0.30 0.32 0.12 0.36
F_OGen 0.35 0.36 0.15 0.35
M_Ogen 0.35 0.21 0.20 0.42
M_FLGen 0.21 0.19 0.36
Cons_Od 0.68 0.13
Consumer: 1(good) – 6 (bad)
FAT
MUSCLE
Aluwé et al 2012Consumer: 1(good) – 6 (bad)
Denmark France Italy Poland Total
N 109 128 121 118 476
Age (years)
<25 5.7 21.8 13.2 22.9 16.4
25-44 29.8 49.2 43.0 22.9 36.7
45-59 43.3 18.8 24.0 33.9 29.3
>60 21.2 10.2 19.8 20.3 17.6
All women Aluwé et al 2018
CAMPIG PROJECT
METHODOLOGY – SAMPLE PREPARATION
Tint= 80ºC, 10-12 min
Aluwé et al 2018
Each consumer:- 1 pair castrate-castrate- 4 pairs boar-castrate/castrate-boar
PREFERENCE:Which product do you like more with respect to the smell?Which product do you like better in terms of taste?
METHODOLOGY – DESIGN & QUESTIONNAIRE
Meat patties 20 % fatAndrostenone from 0.5 to 2 ppmSkatole from 0.10 to 0.40 ppm
Aluwé et al 2018
AND sensitivity
SKA sensitivity No Yes Very Total
Overall No 30.0 9.2 1.3 40.5
n=476 Yes 35.7 16.0 7.8 59.5
Total 65.8 25.2 9.0 100.0
METHODOLOGY – SENSITIVITY
Low AND (0.5 ppm)High AND (5 ppm)SKA (1 ppm)
Aluwé et al 2018
MAPSConsumer dissatifactionby AND, SKA and SENS
A map for Odour and onefor Flavour
Each stakeholder can use the map to decide whereto cut.
Aluwé et al 2018
Aluwé et al 2018Campig Report, 2012
• The preference for the boar patties decreased with increasing SKA content. At low SKA content, the preference for the boar meat patties also decreased with increasing AND level, the more so in the subpopulation of consumers that are especially for consumers sensitive to AND
• It was not possible to determine a clear preference/rejection threshold for AND and SKA as the decrease in liking or preference was gradual. Any sorting limit therefore depends on the risk the stakeholders are willing to take.
CAMPIG: CONCLUSIONS
Christensen et al., 2018
Christensen et al., 2018
Model 1
Critical: random consumer effect 90th percentile in the estimated population consumer likingPopulation-average: consumer population averaged on the probability scaleTypical: random consumer effect =0
Model 2
Christensen et al., 2018
Estimated binary distribution of SKA and AND on original scale and log10 scale. Each dot entire male, and the curves are density contours for the estimatedbivariate normal distribution
Model 3
Christensen et al., 2018
Estimated % of discarded EM pigs as function of sorting limits for SKA and AND
Effect of sorting limits on the risk of dislike in % for EM pigs; the estimated riskof dislike for CM coincides with 9% contour
Christensen et al., 2018
6.2% of EM
Maria Font i Furnolsmaria.font@irta.cat
1
Human nose methods, main characteristics, advantages-
disadvantages
Dra. Núria Panella-Riera
(nuria.panella@irta.cat)
October, 8th, 2018
http://www.ca-ipema.eu/
2 Bekaert, K. (2013)
There is a need of accurate measurements of boar taint compounds
for research purposes ...To detect tainted
meat before it reaches
consumers
...to identify and understand factors
affecting variations in androstenone and skatole levels, ...
...to develop methods to reduce boar taintº
Why do we need to determine boar taint?
...to develop methods mask boar taint
3
Detection methods applied in the abattoir.
Carcass free of boar taint
Boar tainted carcasses
Carcass identification according to boar
taint level
Method to classify carcasses according to
boar taint
How are they commercialised?
4
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
5 Mathur et al., 2012
Consist of identifying boar tainted carcasses with sensory assessment.
Assessors smell fat carcasses right after heating it.
It requires intensive training of the assessors.
Despite the limitations of a sensory methodology used at the slaughter line, this method is currently used as a routine method in different European countries (i.e. The Netherlands, Germany, Belgium, Denmark, France, and Spain).
Human nose methodology. Main characteristics.
6 Backus et al., 2017
Low cost method with high throughput.
It is a method that helps in making progress.
i.e. feedback information for suppliers
Practicable for…
… slaughter line detection
… breeding purposes
… method that fulfils requirements of Dutch-German retailers
Human nose methodology. Main characteristics.
7 Backus et al., 2017
https://www.q-s.de/documentcenter/dc-slaughtering-deboning.html
Human nose methodology. Main characteristics.
Companies that slaughter entire males or cannot exclude this possibility in the future must have procedures in place to ensure reliable detection of carcasses with potential boar taint. Where detection is via sense of smell, the following criteria must at least be met:
8
CONS
It is required a training of the assessors, and to keep them trained.
Rotation of the assessors (i.e. 20 min intervals) is needed to avoid fatigue.
It is important to “believe” in this method (assessors and management team motivated).
It needs strategic decisions from the meat company: How do we include this information on the production line? What do we do with the tainted carcasses?
PROS
Immediate response.
Correlated to the sensory perception of the consumer.
Human nose methodology. Main characteristics.
9
The industry needs a balance of ...
... risk of costumer complaints (too low
sensitivity)...
... pork industry cost due to too many false positives (too low
specificity).
...against...
Human nose methodology. Main characteristics.
10
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
11
At-line: analysis in separate laboratory. The sample is extracted from the carcass and sent to an in-house laboratory where it is analysed.
SamplingTransport and
logistics sampleAnalysis
PLC, database &
report
On line: measurement at the slaughter line. The method can be implemented directly at the slaughter line without physically removing a sub-sample.
Local
heatingAssessment
PLC, database &
report
PLC: Programable logical controllers
Nielsen et al, K. (2013)
Type of Human Nose methods
12
Sample location(fat)
Heating Routine use
Use slaughterline
Samples per hour
1 Neck Soldering iron Yes No 550
2 Neck Boiling water Yes No 40
3 Neck Gas powered torch heated plate
Yes Yes 600
4 Long.dorsi Boiling water No No 5
5 Neck Microwave Yes No 30
BOARCHECK project, 2012 ( a DK, DE, NL, FR, BE i ES)
Important reported method details from the questionnaires on sensory methods.
Type of Human Nose methods
13 Backus et al., 2017
On-line (at slaughter line) At-line: at the laboratory
Type of Human Nose methods
14 Backus et al., 2017
Flaming soldering iron
In slaughter line
At slaughter speed
250-300 samples during 30
min.
Team of trained panellists
Electric soldering iron
In a separated room (“laboratory”) with good ventilation
At own speed
max. 100 samples
Team of trained panellists
On-line: at slaughter line At-line: at the laboratory
Type of Human Nose methods
15
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for
boar taint (May 2013)
7. Final remarks
16
Human nose applied in a Dutch company (2012)
Simple identification of
tainted carcasses
Type of Human Nose methods: on-line.
17
Human nose methodology applied in an Spanish abattoir (450 carcass/h; 2014)
Type of Human Nose methods: on-line.
18
Human nose applied in a Spanish company (600 carcass/h; 2018)
Type of Human Nose methods: on-line.
19 Boars heading 2018
Type of Human Nose methods: on-line.
20
On line test for the human nose method in a Spanish company (2014).Steps: 1. bone dust removal, 2. heat/melt fat, 3. sniffing carcass.
Type of Human Nose methods: on-line.
21
Type of Human Nose methods: on-line. Tools.
22
Type of Human Nose methods: on-line. Tools.
23
Type of Human Nose methods: on-line. Tools.
24 Nielsen et al, K. (2013)
It is important to register individual animal ID, sex of the animal and sample ID.
Sample should be representative of the entire animal
It is important to ensure the reproducibility between different assessors on an adequate level and to ensure that the analytical results do not “drift” from day to day.
Type of Human Nose methods: on-line. Requirements.
25 Nielsen et al, K. (2013)
Type of Human Nose methods: on-line. Requirements.
26
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
27
Type of Human Nose methods: at-line.
28
How do we perform fat sampling?
Type of Human Nose methods: at-line.
29
Remarks regarding the fat collection:
Amount of fat available (preferably, several small pieces so that each assessor smell a new piece/avoid utilization of re-heat the same piece)
Fat temperature: at room temperature or warm (approx. 36 ºC)
Type of Human Nose methods: at-line.
30
For the sensory evaluation
1. Skewer the samples (with forceps)
2. Heat the sample by rubbing a hot iron (~240 ºC) until it appears white, glassy/shinny, blistery, sweaty.
3. Sniff the fat sample about 3 cm from the nostrils.
4. After each evaluation theheated part should be cut off (so that each assessor evaluate a freshly cut surface).
Trautman et al., 2016
Type of Human Nose methods: at-line.
31
Type of Human Nose methods: at-line. Tools.
32
Type of Human Nose methods: at-line. Tools.
33
Analysis in separate laboratory: The sample is extracted from the carcass and sent to an in-house laboratory where it is analysed.
SamplingTransport and
logistics sampleAnalysis
PLC, database &
report
PLC: Programable logical controllers
Nielsen et al, K. (2013)
It is important to register individual animal id; sex of the animal, sample ID (pre-marked disposable vials),
Sample should be representative of the entire animal,
Preferably, use of disposable items to minimize cleaning and cross-contamination,
Type of Human Nose methods: at-line.
34
Analysis in separate laboratory:
Nielsen et al, K. (2013)
Type of Human Nose methods: at-line.
35
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
36
Main steps for training the assessors
Preparation of smell strips:
1. Preparation of the solutions of androstenone and skatole standards
2. Preparation of smell strips
37
Main steps for training assessors
First stage: Selection of assessors
1. Sensitivity test for androstenone and skatole (smell strips)
Trautman et al., 2014
38
SESSIÓ 1 . 1.1. Olor sexual: compostos responsables
To ensure the constant release of the composites of the paper strips, it is recommended to …
save for 7 days max. use 4 times max.
(according to measurements made in the head space)
Main steps for training assessors
First stage: Selection of assessors
1. Sensitivity test for androstenone and skatole (smell strips)
Trautman et al., 2014
39
There is a need for intensive training of the assessors
Assessors should be motivated to be part of the SMELLING TEAM
Recruitment and selection of assessors to be part of the SMELL MASTER TEAM
1st/ Announcement of an informative session for all the staff
2nd/ Informative session to motivate volunteers
3rd/ Presentation of volunteers
4rt/ Sensitivity test for androstenona and skatole to built the SMELL MASTER TEAM
5th/ Training process (in the laboratory and on line)
6th/ Start to smell carcasses
40
Main steps for training assessors
Second stage: Training with smell strips (laboratory)
Example of tests:
1. Odour discrimination test (triangle tests for androstenone and skatole)
2. Odour threshold test, Odour identification tests
3. Pair test , triangular tests, ranking test
Trautman et al., 2014
Third stage: Training with fat with different levels of boar taint. Example of tests:1. Odour threshold test, Compounds identification test2. Pair test, triangular tests, ranking test 3. Familiarization with the procedure (environment,
speed,...)4. On line test next to a experienced assessor
41Ampuero, et al 2011; Haugen et al., 2012
There is a need
of a reference
method
Attention on the methodology used for the chemical analyses of Androstenone and Skatole levels. There has been used different extraction methodologies
60 %
40 %
ug/g adipose tissue
ug/g pure fat
Androstenone 1
≡1.7
Skatole 1 1.6
Indole 1 1.2
Main steps for training assessors
Third stage: Training with fat with different levels of boar taint
42
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
43
Survey in slaughterhouses 35 abattoirs (31 from EU) in 10 different countries (8 in the EU) .
(EU: Belgium, Denmark, France, Germany, Netherlands, Spain, United kingdom;
Third countries: Canada, New Zealand, Norway)
Among the 31 abattoirs,
1. 24 slaughtered entire male pigs or were planning to do so during the following years
2. Only Belgium was slaughtering immunocastrated pigs.
3. 12 abattoirs (BE, DK, FR, DE i NL) had a boar taint detection method (4 with a Human nose under development)
http://www.ca-ipema.eu/meat-quality Projecte BOARCHECK, 2012 ( a DK, DE, NL, FR, BE i ES)
Survey about the situation of rapid methods for boar taint (May 2013)
44
/.../
4. Nine abattoirs had a method based on sensory analyses, 1 with a chemical analyses of skatole.
5. The abattoirs with a method to determine boar taint, assessed all the entire male pigs.
6. Scores given for the boar taint:
2 levels (YES/NO) in 6 companies
More than 2 levels in 3 abattoirs
7. Costs related to the detection (answers from 3 companies)
Initial investment: median 10000 € (3600 – 12000)
Operational cost: Median 1.5 €/boar slaughtered (0.20 – 2.68 €)
http://www.ca-ipema.eu/meat-quality Projecte BOARCHECK, 2012 ( a DK, DE, NL, FR, BE i ES)
Survey about the situation of rapid methods for boar taint (May 2013)
45http://www.ca-ipema.eu/meat-quality Projecte BOARCHECK, 2012 ( a DK, DE, NL, FR, BE i ES)
Method performance traits Requeriments
Method capacity
Capacity/analysis pr hr 100-800 carcass
Analysis speed pr sample 4-40 seg
Sampling time pr sample 0.5-20 min
Result reporting
At-line method < 30 min
On-line method <1 min
Costs
Running cost pr carcass < 2 eur
Method performance
Survey about the situation of rapid methods for boar taint (May 2013)
46
Table of contents:
1. Human Nose methods. Main characteristics
2. Type of Human nose methods
3. On-line methods
4. At-line methods
5. Main steps for training the assessors
6. Survey about the situation of rapid methods for boar taint (May 2013)
7. Final remarks
47
Nowadays, there is not a dedicated on- or at-line instrumental measurement system available for sorting of boar tainted carcasses that measures both androstenone and skatole.
Different sensory methods have been developed and are functioning in abattoirs, either on-line or at line. Whatever the case, the performance of these systems need validation.
If sensory methods are used for boar taint detection, there is a need of a good program for the training of the assessors and plan to keep them trained.
Therefore, there is still need in a fully validated and a reliable on-line test for use in abattoirs to remove tainted meat.
Final remarks
48
Muchas gracias Moltes gràcies
48
Thank you very much
49
References of interest
Ampuero, S.K., Verkuylen, B., Dahlmans, H., Hortos, M., García-Regueiro, J.A., Dahl, E., Odresen, O., Feitsma, H., Mathur, P.K., Harlizius, B., 2011. Inter-laboratory comparison of methods to measure androstenone in pork fat. Animal, 5(10): 1-9.
Bekaert, K. (2013). Chemical and sensory detection of boar taint. Doctor in Veterinary Science, Ghent University.
G.Backus, 2017. Human nose scoring System for boar taint. Prague. Cost IPEMA (February 2017). http://www.ca-ipema.eu/meat-quality
Haugen, J. E., C. Brunius and G. Zamaratskaia (2012). "Review of analytical methods to measure boar taint compounds in porcine adipose tissue: The need for harmonised methods." Meat Science 90(1): 9-19.
Haugen, J.E., Panella-Riera, N., de la Calle, B. 2013. D1.1. Method survey. Boarcheck project. D1.1 Method survey
Keller, A., Zhuang, H., Chi, Q., Vosshall, L. B., & Matsunami, H. (2007). Genetic variation in a human odorant receptor alters odourperception. Nature, 449(7161), 468–472.
Liu, X., H. Schmidt and D. Mörlein (2016). "Feasibility of boar taint classification using a portable Raman device." Meat Science 116: 133-139.
Mathur PK, Napel J ten, Crump RE, Mulder HA, Knol EF. Genetic relationship between boar taint compounds, human nose scores, and reproduction traits in pigs. J Anim Sci. 2013;91(9):4080–9. DOI: 10.2527/jas.2013-6478.
Mathur, P. K., J. ten Napel, S. Bloemhof, L. Heres, E. F. Knol and H. A. Mulder (2012). "A human nose scoring system for boar taint and its relationship with androstenone and skatole." Meat Science 91(4): 414-422.
Sorensen, K. M., C. Westley, R. Goodacre and S. B. Engelsen (2015). "Simultaneous quantification of the boar-taint compoundsskatole and androstenone by surface-enhanced Raman scattering (SERS) and multivariate data analysis " Analytical and Bioanalytical chemistry: 10.
Trautmann, J., J. Gertheiss, M. Wicke and D. Mörlein (2014). "How olfactory acuity affects the sensory assessment of boar fat: A proposal for quantification." Meat Science 98(2): 255-262.
Wang, Q., S. Ding, K. Hamouche and C. Yu (2014). Evaluating meat quality using Ramman Spectroscopy. Proceedings International Converence of Agricultural Engineering, Zurich.
50
5. Links of interests
http://www.ca-ipema.eu/oeiras-presentations
https://www.q-s.de/documentcenter/dc-slaughtering-deboning.html
Recommended