Moderator : Gabriel Lepousez
9. Hanneke Botha - South African sweet Chenin blanc wine styles: chemical, sensory and consumer perception aspects
Sweet wines have a special niche in the international wine market. Chenin blanc is used extensively for the production of Natural Sweet NS, Special Late Harvest SLH, Noble Late Harvest NLH and Straw wines SW in South Africa. Despite this prominent position, limited scientific information is available on the chemical and sensory properties of sweet Chenin blanc wines. Consumers’ perception and preferences of these wines are also unknown.
Methods and materials
A selection of twenty wines (five per style) were subjected to intensive chemical, sensory and consumer testing. For the sensory analysis, 2 wines each from three of the sub-categories (n = 6) (SLH, NLH and SW) were presented to a trained panel for Generic Descriptive Analysis. These wines were also analysed by a consumer panel to identify their degree of liking and consumer perceptions.
Chemical profiles of non-volatiles and volatiles were obtained for all natural sweet Chenin blanc wines. Based on the analyses done, the wines mainly separate due to variance in glucose, fructose, glycerol and gluconic acid. Sensory evaluation resulted in the generation of more than 30 sensory descriptors of sufficient discrimination ability to distinguish between the different sweet styles. Consumers’ knowledge and awareness of the sweet category was low. Some socio-economic drivers (economic and health considerations) of consumers’ perceptions of the sweet wines were identified.
Results of this study make a significant contribution to available knowledge and our understanding of this genre. Opportunities for enhancement of consumers’ experience of the category were identified. Platforms for chemical and sensory investigation on sweet wines were laid.
Session VI - Taste, tastes of Chenin blanc wines
8. Dr. Jeanne Brand with Dr. Leanie Louw and Dr. Hélène Nieuwoudt as co-authors - Pivot Profile and Polarised Sensory Positioning: The pros and cons when used for benchmarking of Chenin
Benchmarking is an important product development tool when the aim is to penetrate new markets, understand underperformance of a product or re-position a product at a new price-point. This process can lead to branding or re-branding of products. Sensory evaluation and subsequent comparison of profiles are essential for benchmarking of wines, and rapid evaluation methods play an essential role in this process.
In this presentation, we discuss the pros and cons of three rapid sensory evaluation methods: Check-all-that-apply (CATA), Pivot Profile (PP), and Polarised Sensory Positioning (PSP) to benchmark wine.
With CATA, products’ sensory attributes are evaluated one-at-a-time. Sensory judges select the attributes that describe a sample best from a pre-determined list of terms, or a flavour wheel. The comparison of the products is then done with subsequent statistical analysis.
PP and PSP are reference-based methods where products are compared directly in toto to each other. With the PP method, each sample is compared to a reference (i.e. the wine sample considered as the benchmark), called the pivot. Sensory panellists provide the attributes that are perceived as “less intense” and “more intense” in the sample than the pivot.
PSP entails that the difference between each sample and the reference (benchmark-sample) is rated on a line scale that ranges from “exactly the same” to “completely different”.
Results obtained with the rapid methods in sensory evaluation of two sets, each of 5 premium quality Chenin Blanc and Sauvignon blanc wines are presented. We visualise the data using heat maps, a new approach in sensory science. Panel performance and the difficulty of the method were assessed. The panel experienced CATA as the easiest method to perform, but the in toto direct comparison of samples gave superior discrimination between samples.