Comparison of Home Use Test (HUT) and Central Location Test (CLT) by the use of Preference Mapping

Anna Sverkén (1), Annika Åström (1), Karin Wendin (2)
1) SIK-the Swedish Institute for Food and Biotechnoloy, Box 5401, SE-402 29 Gothenburg, Sweden,
2) IDEON, SE-223 70 Lund, Sweden

Acceptance tests can be performed as CLT with a high degree of control or as HUT under more natural conditions. It has been stated that differences between CLT and HUT are dependent on test situation as well as on product type.

The aim of this study was to compare CLT to HUT in the acceptance of flavoured chocolate bars, using the same recruitment criterions.

Five chocolate bars were rated for appearance, odour, taste, texture and overall liking on a 9point hedonic scale. The numbers of respondents were 129 (CLT) and 116 (HUT), respectively. CLT was performed in Gothenburg and HUT was performed with respondents from all over Sweden. A trained sensory panel profiled the bars by QDA. ANOVAs, clustering and PLS were used in order to perform Preference Mapping for each method.

Results showed that respondents in HUT gave higher liking scores along with fewer and less verbose comments than in CLT. Four clusters were identified in HUT and five in CLT. Preference Mapping showed that respondents in one cluster both in HUT and CLT scored all products high independently of each products sensory profile, respondents in three of the clusters (HUT and CLT) favoured special product attributes, while respondents in the fifth cluster (only CLT) ranked all products low.

The higher scores in HUT coincided well with earlier studies. However, clusters in HUT were not as distinct as in CLT. The fifth and most negative cluster of respondents found only in CLT seemed to be a result of clearly negative respondents. Considering chocolate bar as a rather simple product, the result seemed to be more dependent on test situation than other studies indicated, giving that impact of test situations have to be further investigated.