Euphytica 111: 79–90, 2000.
© 2000 Canadian Crown. Printed in the Netherlands.
79
Sensory evaluation as a selection tool in apple breeding
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C.R. Hampson, H.A. Quamme, J.W. Hall, R.A. MacDonald, M.C. King & M.A. Cliff
Agriculture and Agri-Food Canada, Pacific Agri-Food Research Centre, Summerland, B.C. Canada V0H 1Z0
Received 27 February 1998; accepted 10 June 1999
Key words: appearance, flavour, fruit quality, Malus × domestica, methods, texture
Summary
Several conventional sensory methods were adapted to provide a procedure that is suitable for screening apple
(Malus × domestica) breeding selections for dessert quality. Trained judges were presented with randomized coded
samples (apple slices) and asked to rate them on 0 to 9 bipolar hedonic (liking) scales for texture and flavour, and
0 to 9 unipolar intensity scales for skin toughness, crispness, hardness, juiciness, aroma, sweetness and sourness.
Appearance liking was rated on coded samples of five whole apples, using the 0 to 9 hedonic scale. A minimum
panel size of eleven judges was generally sufficient to obtain statistical discrimination of one point on the 0 to 9
scales. Panel mean scores for breeding selections relative to standards have been consistent from panel to panel
and year to year. A subset of selections and cultivars was rated for appearance and taste by consumers in blind taste
tests. In-house panel findings were comparable to consumer ratings for taste and appearance liking, with a few
exceptions in appearance. Panel mean scores for texture and flavour liking were regressed on texture and flavour
components. Crispness accounted for about 90% of the variation in texture liking. Juiciness, aroma, sweetness
and sourness were all important to flavour liking, but their relative importance changed from year to year and in
total accounted for only about 60% of variation in flavour liking. Perceived sweetness and sourness were better
predictors of liking than analytical measurements of soluble solids and titratable acidity. Formal sensory evaluation
can be used successfully for screening breeding selections, and may provide more reliable data than the opinions
of only one or two people.
Introduction
The widespread consumer acceptance of ‘new’ apple
cultivars, such as Fuji, Braeburn and Gala, over
the past decade is usually attributed to their superior
dessert quality (Stebbins, 1992). Any newly released
apple which seeks to replace or compete with the cul-
tivars now available in the market must be of compar-
able or superior eating quality. Therefore, it behooves
apple breeders to screen breeding selections for the
eating quality of the fruit.
Unfortunately, eating quality is difficult to meas-
ure objectively. Analytical measurements of soluble
solids (% SS), titratable acidity (TA) and firmness
have shown poor correlation with sensory perceptions
of sweetness, sourness and texture (Bourne, 1979;
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The Canadian Crown reserves the right to retain a non-
exclusive, royalty free licence in and to any copyright
Watada et al., 1981). The traditional breeding prac-
tice has been to rely on the experience and opinions
of one or two individuals to identify the most prom-
ising and tasty selections among the many generated
by controlled crosses, but no objective evidence of
the soundness of this method appears to exist. Many
varietal releases never achieve commercial success,
and sometimes eating quality of the fruit is a factor.
Consumer tests are impossible for routine screening
of breeding selections, because of the limited avail-
ability of fruit and other resources required for the
large number of evaluations (75 to 200 consumers)
that may be needed (Meilgaard et al., 1987). The de-
velopment of sensory methods which maximize the
use of resources and provide a preliminary prediction
of consumer response would be useful for screening
breeding selections.