M Wang, N Emmambux &  H L de Kock*

Department of Food Science, University of Pretoria, Pretoria 0002, South Africa

Hedonic adjustment to the novel sensory properties of the natural juice manufactured from the rehydrated dried fruit of an underutilised wild plant Vangueria infausta was determined as a function of repeated exposure to the juice, as well as neophobia level and health consciousness of consumers.  In this form the juice had significantly higher vitamin C, lower sugar and higher fibre contents compared to a commercial wild fruit juice, marula (Sclerocarya birrea subsp. caffra).  However, the former juice was clearly less sweet and with a novel flavour compared to commercial juices. 

Two groups of 50 consumers evaluated 50 ml of both juices once per day over three days.  The control group rated hedonic rating, willingness to buy and familiarity at the first exposure.  This group evaluated hedonic rating and willingness to buy during the next two evaluation sessions.  The experimental group did exactly the same but on each occasion they also received information about the superior health properties of one of the juices, although the relevant juice was not identified. The groups did not differ in neophobia level nor level of health consciousness.

The expectation that repeated exposure would increase the hedonic ratings for the novel juice because unfamiliarity with the novel flavour would decrease, did not materialise.  Information on the nutritional and health aspects of the juice superior health properties of one of the juices did not positively influence hedonic responses. Both groups on each of the three occasions significantly preferred the commercial marula juice.  It was concluded that the inherent sensory properties of the novel juice did not meet the expected hedonic level for a fruit juice.  In addition, the superior taste properties of the commercial juice included enhanced the contrast effect in turn negating the presumed positive effects of exposure and health related information.