DEVELOPMENT OF QUALITY CONTROL TOOLS AND A
TASTE PREDICTION MODEL FOR ROOIBOS
Bianca Jolley
Thesis presented in partial fulfilment of the requirements for the degree of
Master of Science in Food Science
Department of Food Science
Faculty of AgriSciences
Stellenbosch University
Supervisor: M. Muller
Co-supervisor: E. Joubert
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Table B2 DSA aroma intensity data (out of 100) for the negative attributes, for the Western Cape samples used for instructed sorting, based on aroma quality.
a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Production
area Sample Year
AHay/dried grass AGreen ARotting plant water ABurnt caramel ADusty AMusty/ mouldy AMedicinal/ rubber ASeaweed WC AA 2009 1.7 2.6 NAa NA 0.0 NA NA NA WC 5A 2009 2.2 1.9 NA NA 0.0 NA NA NA WC 14D 2009 10.9 14.6 NA NA 1.0 NA NA NA WC 2A 2011 14.5 3.4 NA 0.0 NA 0.0 0.0 NA WC 4B 2011 12.6 8.1 NA 0.8 NA 1.1 1.5 NA WC 6D 2011 18.3 8.8 NA 9.1 NA 8.4 39.2 NA WC 13C 2012 12.8 3.0 3.0 2.9 4.7 2.4 2.8 0.0 WC 6D 2012 12.9 11.5 2.7 0.5 4.3 3.6 13.8 1.2 WC 1A 2013 11.3 2.7 2.6 0.0 0.8 2.2 6.5 0.0 WC 7C 2013 9.4 5.7 0.7 4.1 0.4 1.5 1.8 0.0 WC 1D 2013 22.0 11.7 2.0 0.0 0.9 2.7 0.2 0.0
Stellenbosch University http://scholar.sun.ac.za
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Table B3 DSA aroma intensity data (out of 100) for the positive attributes, for the Northern Cape samples used for instructed sorting, based on aroma quality
a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Production
area Sample Year
ARooibos-woody
AFynbos-floral AHoney
AFruity-sweet AApricot ACaramel
ACooked
apple ASpicy ACitrus
NC 1A 2009 45.88 31.25 31.82 19.45 NAa 3.87 NA 4.57 NA NC 4A 2010 45.55 25.17 31.63 19.58 NA 6.98 NA 6.07 NA NC 3C 2010 35.93 19.58 14.68 8.43 NA 3.97 NA 3.32 NA NC 5A 2011 45.12 29.40 31.62 7.13 NA 1.17 NA 0.80 NA NC 3B 2011 37.30 22.55 19.18 25.22 NA 2.95 NA 0.33 NA NC 4C 2011 41.88 14.73 19.28 5.47 NA 2.03 NA 0.00 NA NC 1A 2012 31.02 26.85 14.00 16.95 17.31 21.50 8.43 8.13 0.00 NC 3A 2012 32.95 25.18 14.22 10.48 8.75 16.37 2.65 4.92 0.00 NC 11B 2012 37.14 28.19 23.63 8.93 3.55 7.37 0.00 1.02 0.00 NC 2D 2012 30.34 23.91 16.33 4.85 2.03 6.58 0.33 0.33 2.00 NC 3A 2013 35.23 29.08 14.73 21.31 17.50 13.35 0.00 0.00 1.91 NC 4D 2013 41.48 32.25 17.23 11.52 10.67 25.21 0.75 1.23 0.00
Stellenbosch University http://scholar.sun.ac.za
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Table B4 DSA aroma intensity data (out of 100) for the negative attributes, for the Northern Cape samples used for instructed sorting, based on aroma quality
a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Production
area Sample Year
AHay/dried grass AGreen ARotting plant water ABurnt caramel ADusty AMusty/ mouldy AMedicinal/ rubber ASeaweed NC 1A 2009 8.20 2.32 NAa 0.95 NA 0.00 1.32 NA NC 4A 2010 9.33 1.93 NA 1.47 NA 0.35 0.87 NA NC 3C 2010 10.30 20.63 NA 0.00 NA 7.17 13.74 NA NC 5A 2011 9.23 4.42 NA 0.00 NA 2.53 2.17 NA NC 3B 2011 11.12 16.60 NA 0.52 NA 2.82 1.73 NA NC 4C 2011 15.73 10.72 NA 8.33 NA 7.63 28.37 NA NC 1A 2012 5.57 2.38 0.00 3.24 0.33 0.67 0.00 0.00 NC 3A 2012 7.25 4.25 0.88 3.48 0.42 0.84 0.52 1.02 NC 11B 2012 12.62 5.00 0.64 2.28 1.98 0.03 1.42 1.00 NC 2D 2012 11.20 18.63 2.91 4.60 0.42 4.48 10.41 0.33 NC 3A 2013 5.94 1.15 0.00 0.40 0.85 1.00 0.40 0.00 NC 4D 2013 5.19 4.79 0.71 6.09 0.00 1.25 0.21 0.00
Stellenbosch University http://scholar.sun.ac.za
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Table B5 DSA flavour intensity data (out of 100) for the positive attributes, for the Western Cape samples used for instructed sorting, based on palate quality
Production
area Sample Year
FRooibos-woody
FFynbos-floral FHoney
FFruity-sweet FApricot FCaramel
FCooked
apple FSpicy FCitrus
WC AA 2009 37.8 7.6 NA NA NA 2.2 NA NA NA WC 5A 2009 41.9 10.2 NA NA NA 5.8 NA NA NA WC 14D 2009 38.6 8.2 NA NA NA 0.0 NA NA NA WC 2A 2011 42.2 17.5 7.9 1.6 NA 0.3 NA 0.0 NA WC 4B 2011 42.2 16.5 3.1 1.5 NA 0.3 NA 0.3 NA WC 6D 2011 34.3 8.4 1.0 0.8 NA 1.0 NA 0.4 NA WC 13C 2012 35.3 23.4 3.9 3.3 0.3 1.7 0.0 0.0 0.0 WC 6D 2012 31.9 26.8 2.2 0.7 0.0 0.3 0.0 0.3 0.0 WC 1A 2013 40.0 18.1 6.0 0.0 0.0 1.7 0.0 0.0 0.0 WC 7C 2013 34.6 21.7 2.0 7.0 2.8 4.2 0.0 0.0 0.0 WC 1D 2013 29.3 17.5 1.6 3.0 1.0 0.3 0.7 0.0 0.0 a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Stellenbosch University http://scholar.sun.ac.za
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Table B6 DSA flavour intensity data (out of 100) for the negative attributes, for the Western Cape samples used for instructed sorting, based on palate quality
Production
area Sample Year
FHay/dried grass FGreen FRotting plant water FBurnt caramel FDusty FMusty/ mouldy FMedicinal/ rubber FSeaweed WC AA 2009 6.8 1.2 NA NA NA NA NA NA WC 5A 2009 2.7 0.0 NA NA NA NA NA NA WC 14D 2009 13.6 8.7 NA NA NA NA NA NA WC 2A 2011 10.1 0.0 NA NA NA NA 0.1 NA WC 4B 2011 9.3 1.7 NA NA NA NA 0.0 NA WC 6D 2011 9.4 7.3 NA NA NA NA 24.0 NA WC 13C 2012 15.9 2.1 1.5 1.3 3.6 1.1 5.9 0.0 WC 6D 2012 12.0 7.7 2.1 0.3 0.8 0.3 0.3 0.0 WC 1A 2013 13.2 2.0 2.5 0.0 0.0 0.4 3.3 0.0 WC 7C 2013 11.3 4.3 0.3 1.2 0.0 0.0 0.0 0.0 WC 1D 2013 20.8 6.6 0.8 0.0 0.0 1.3 0.3 0.0 a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Stellenbosch University http://scholar.sun.ac.za
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Table B7 DSA taste and mouthfeel intensity data (out of 100), for the Western Cape samples used for instructed sorting, based on palate quality
Production area Sample Year Sweet Sour Bitter Astringent
WC AA 2009 20.7 1.4 2.2 12.2 WC 5A 2009 17.9 1.4 3.1 19.2 WC 14D 2009 13.1 1.7 5.3 21.4 WC 2A 2011 25.3 2.3 1.4 23.0 WC 4B 2011 24.7 3.1 0.8 24.6 WC 6D 2011 19.1 2.1 3.8 27.0 WC 13C 2012 18.2 3.3 3.1 23.7 WC 6D 2012 23.0 3.9 1.7 21.2 WC 1A 2013 19.9 3.0 5.6 28.3 WC 7C 2013 20.8 9.3 1.3 25.5 WC 1D 2013 19.3 7.7 1.3 25.3
Stellenbosch University http://scholar.sun.ac.za
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Table B8 DSA flavour intensity data (out of 100) for the positive attributes, for the Northern Cape samples used for instructed sorting, based on palate quality
Production
area Sample Year
FRooibos-woody
FFynbos-floral FHoney
FFruity-sweet FApricot FCaramel
FCooked
apple FSpicy FCitrus
NC 1A 2009 42.25 18.38 3.48 2.88 NAa 1.17 NA 1.59 NA NC 4A 2010 46.68 17.82 9.00 3.42 NA 1.07 NA 0.27 NA NC 3C 2010 36.80 14.50 2.60 0.67 NA 1.00 NA 0.00 NA NC 5A 2011 39.60 19.18 7.13 1.52 NA 0.00 NA 0.00 NA NC 3B 2011 39.77 18.33 5.57 3.78 NA 0.83 NA 0.00 NA NC 4C 2011 42.16 9.12 2.30 0.78 NA 0.50 NA 0.00 NA NC 1A 2012 32.98 24.93 2.68 10.20 1.41 9.98 1.88 4.38 0.00 NC 3A 2012 32.97 22.89 3.17 6.05 3.22 6.50 0.00 1.74 0.00 NC 11B 2012 35.35 27.02 3.78 5.20 0.00 3.52 0.02 0.27 0.00 NC 2D 2012 31.25 23.10 2.88 2.47 0.67 2.00 0.00 0.00 0.00 NC 3A 2013 34.38 25.50 1.60 6.31 3.00 3.90 0.00 0.37 0.43 NC 4D 2013 38.69 24.27 0.67 4.23 3.37 6.43 0.00 0.57 0.00 a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Stellenbosch University http://scholar.sun.ac.za
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Table B9 DSA flavour intensity data (out of 100) for the negative attributes, for the Northern Cape samples used for instructed sorting, based on palate quality
Production
area Sample Year
FHay/dried grass FGreen FRotting plant water FBurnt caramel FDusty FMusty/ mouldy FMedicinal/ rubber FSeaweed NC 1A 2009 4.95 0.00 NAa NA NA NA 0.53 NA NC 4A 2010 7.65 0.50 NA NA NA NA 0.00 NA NC 3C 2010 8.30 12.53 NA NA NA NA 5.93 NA NC 5A 2011 5.43 0.50 NA NA NA NA 0.00 NA NC 3B 2011 11.63 4.36 NA NA NA NA 1.15 NA NC 4C 2011 13.72 4.92 NA NA NA NA 13.59 NA NC 1A 2012 10.67 0.52 0.00 1.17 1.52 0.64 0.00 0.00 NC 3A 2012 14.03 3.31 0.43 1.82 0.40 0.31 0.00 0.00 NC 11B 2012 12.24 1.37 0.33 0.33 0.00 0.00 0.00 0.00 NC 2D 2012 16.00 14.05 0.33 2.00 0.00 0.25 1.35 0.00 NC 3A 2013 9.71 1.10 0.00 0.35 0.00 0.31 0.00 0 NC 4D 2013 9.17 2.46 0.00 1.50 0.00 0.56 0.00 0 a
Descriptive sensory analysis was not done for these specific attributes during this particular year of analysis. Stellenbosch University http://scholar.sun.ac.za
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Table B10 DSA taste and mouthfeel intensity data (out of 100), for the Northern Cape samples used for instructed sorting, based on palate quality
Production area Sample Year Sweet Sour Bitter Astringent
NC 1A 2009 24.58 1.60 0.45 22.40 NC 4A 2010 23.35 3.30 3.82 27.98 NC 3C 2010 22.72 3.71 0.93 24.68 NC 5A 2011 23.00 1.15 0.83 23.80 NC 3B 2011 23.78 2.33 1.95 25.78 NC 4C 2011 21.50 0.93 2.50 28.37 NC 1A 2012 21.68 3.05 1.03 21.22 NC 3A 2012 18.88 3.00 0.52 22.52 NC 11B 2012 19.28 2.70 0.98 22.05 NC 2D 2012 16.42 5.97 5.00 23.67 NC 3A 2013 22.00 5.81 1.23 23.90 NC 4D 2013 22.21 4.75 3.06 25.25
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