Fruit and Vegetable Quality

validity. The theoretical basis of the model is presented in this section
of the chapter, which will be followed by examples of its application.
Market segmentation by quality preference and use of a probability
distribution helps overcome the difficulties encountered by variation be-
tween consumers. The QE model provides a framework for identifying
critical quality attributes; generates a measurement of success with a
consumer acceptability equation based on a probability distribution for
each quality-preference segment; and forges linkages between basic, ap-
plied and developmental research. Quality becomes the primary focus
of the research effort rather than merely an evaluative tool for some other
activity. Some critical assumptions are made in applying the quality en-
hancement model: (1) quality characteristics are intrinsic to the fruit or
vegetable, (2) acceptability involves consumer reaction to a fruit or veg-
etable with a given set of characteristics, and (3) contribution of a qual-
ity characteristic to consumer acceptability is a more important selection
criterion than accuracy and precision of the measurement technique.
Adopting a QE perspective provides some profound consequences for
viewing quality within the postharvest chain: (1) meaningful evaluation
of acceptability is performed only at purchase and consumption by the
consumer, thus (2) quality and acceptability cease to become a contin-
uous function over time and become discrete functions at purchase and
consumption, suggesting that (3) management decisions made by the
distributor as well as by the consumer are major factors in enhancing
food quality. The most striking consequence of all is that enhancement
of quality rather than mere maintenance of quality is possible because
the consumer is not comparing quality and acceptability of the product
in hand with that at harvest. Rather, the consumer is comparing quality
and acceptability with an internal level of expectations. Postharvest or
distribution management techniques that can improve the quality as pur-
chased or consumed by the consumer result in true quality enhancement.
Some serious limitations in the QE model include: (1) lack of con-
sideration of price as a factor in acceptability and (2) lack of compari-
son with other items available. Both price (Jordan et al., 1985a, b, 1986;
How, 1991; Malundo, 1996) and comparative availability (Sloof et al.,
1996) affect consumer definition of quality. Also, both price and qual-
ity availability can lead to heightened or lowered expectations and will-
ingness to purchase. Current sensory and consumer testing practice tends
to overemphasize item-to-item comparison (e.g., few consumers conduct
direct challenge studies between competing products). Our work in the
area evaluates acceptability at a reasonable price (“reasonable” as de-

150 FRUIT AND VEGETABLE QUALITY